[linux-next:master] [btrfs] f9d138838a: stress-ng.dir.ops_per_sec 6.4% regression

kernel test robot
2026-04-08T05:53:12Z

Hello,

kernel test robot noticed a 6.4% regression of stress-ng.dir.ops_per_sec on:

commit: f9d138838a78bf2a5263ad3c1d3c05edbc0844d4 ("btrfs: inhibit extent buffer writeback to prevent COW amplification")
https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git master

[still regression on linux-next/master 2febe6e6ee6e34c7754eff3c4d81aa7b0dcb7979]

testcase: stress-ng
config: x86_64-rhel-9.4
compiler: gcc-14
test machine: 64 threads 2 sockets Intel(R) Xeon(R) Gold 6346 CPU @ 3.10GHz (Ice Lake) with 256G memory
parameters:

nr_threads: 100%
disk: 1HDD
testtime: 60s
fs: btrfs
test: dir
cpufreq_governor: performance

In addition to that, the commit also has significant impact on the following tests:

+------------------+-----------------------------------------------+
| testcase: change | fsmark: fsmark.files_per_sec 6.5% regression |
| test parameters | cpufreq_governor=performance |
| | disk=1BRD_32G |
| | filesize=4K |
| | fs=btrfs |
| | iterations=1x |
| | nr_files_per_directory=1fpd |
| | nr_threads=1t |
| | sync_method=fsyncBeforeClose |
| | test_size=4G |
+------------------+-----------------------------------------------+
| testcase: change | fio-basic: fio.write_iops 7.4% regression |
| test parameters | bs=4k |
| | cpufreq_governor=performance |
| | disk=1HDD |
| | fs=btrfs |
| | ioengine=sync |
| | nr_task=1 |
| | runtime=300s |
| | rw=randwrite |
| | test_size=128G |
+------------------+-----------------------------------------------+
| testcase: change | fio-basic: fio.write_iops 6.8% regression |
| test parameters | bs=4k |
| | cpufreq_governor=performance |
| | disk=1HDD |
| | fs=btrfs |
| | ioengine=vsync |
| | nr_task=1 |
| | runtime=300s |
| | rw=randwrite |
| | test_size=128G |
+------------------+-----------------------------------------------+
| testcase: change | fio-basic: fio.write_iops 21.9% regression |
| test parameters | bs=4k |
| | cpufreq_governor=performance |
| | disk=1HDD |
| | fs=btrfs |
| | ioengine=ftruncate |
| | nr_task=1 |
| | runtime=300s |
| | rw=randwrite |
| | test_size=128G |
+------------------+-----------------------------------------------+

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <oliver.sang@intel.com>
| Closes: https://lore.kernel.org/oe-lkp/202604081348.e45317cc-lkp@intel.com

Details are as below:
-------------------------------------------------------------------------------------------------->

The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20260408/202604081348.e45317cc-lkp@intel.com

=========================================================================================
compiler/cpufreq_governor/disk/fs/kconfig/nr_threads/rootfs/tbox_group/test/testcase/testtime:
gcc-14/performance/1HDD/btrfs/x86_64-rhel-9.4/100%/debian-13-x86_64-20250902.cgz/lkp-icl-2sp8/dir/stress-ng/60s

commit:
ed7bc52711 ("btrfs: extract the max compression chunk size into a macro")
f9d138838a ("btrfs: inhibit extent buffer writeback to prevent COW amplification")

ed7bc52711022142 f9d138838a78bf2a5263ad3c1d3
---------------- ---------------------------
%stddev %change %stddev
\ | \
8182 -6.4% 7661 stress-ng.dir.ops_per_sec
34744 ± 7% +49.6% 51981 ± 9% stress-ng.time.involuntary_context_switches
25199 +2.2% 25759 stress-ng.time.minor_page_faults
2310 -4.4% 2208 stress-ng.time.percent_of_cpu_this_job_got
1374 +2.4% 1407 stress-ng.time.system_time
23103691 +1.8% 23527155 stress-ng.time.voluntary_context_switches
2.564e+09 +8.9% 2.793e+09 cpuidle..time
12365 ± 4% +8.5% 13420 perf-c2c.HITM.local
2.42 -7.8% 2.23 iostat.cpu.nice
33.85 -1.6% 33.31 iostat.cpu.system
1.63 -7.5% 1.51 ± 2% iostat.cpu.user
0.70 ± 5% +14.6% 0.81 ± 7% vmstat.procs.b
755798 -3.3% 730692 vmstat.system.cs
482003 -1.9% 472809 vmstat.system.in
0.72 ± 3% +0.1 0.87 ± 7% mpstat.cpu.all.iowait%
2.49 -0.2 2.29 mpstat.cpu.all.nice%
0.08 +0.2 0.27 mpstat.cpu.all.soft%
1.66 -0.1 1.53 ± 2% mpstat.cpu.all.usr%
60.44 +1.3 61.76 turbostat.C1%
39.12 +5.2% 41.14 turbostat.CPU%c1
0.04 +0.0 0.05 turbostat.POLL%
21.71 -1.3% 21.42 turbostat.RAMWatt
0.90 ± 3% +30.9% 1.17 ± 7% perf-sched.total_wait_and_delay.average.ms
1471503 ± 2% -9.1% 1337333 ± 7% perf-sched.total_wait_and_delay.count.ms
0.89 ± 3% +30.9% 1.16 ± 7% perf-sched.total_wait_time.average.ms
0.90 ± 3% +30.9% 1.17 ± 7% perf-sched.wait_and_delay.avg.ms.[unknown].[unknown].[unknown].[unknown].[unknown]
1471503 ± 2% -9.1% 1337333 ± 7% perf-sched.wait_and_delay.count.[unknown].[unknown].[unknown].[unknown].[unknown]
0.89 ± 3% +30.9% 1.16 ± 7% perf-sched.wait_time.avg.ms.[unknown].[unknown].[unknown].[unknown].[unknown]
1.696e+10 -5.1% 1.61e+10 perf-stat.i.branch-instructions
0.42 +0.0 0.44 perf-stat.i.branch-miss-rate%
54.21 -2.0 52.21 perf-stat.i.cache-miss-rate%
2.007e+08 -4.2% 1.922e+08 perf-stat.i.cache-misses
3.645e+08 -2.4% 3.559e+08 perf-stat.i.cache-references
787352 -3.7% 758130 perf-stat.i.context-switches
1.33 +5.5% 1.40 perf-stat.i.cpi
9.793e+10 -3.0% 9.501e+10 perf-stat.i.cpu-cycles
109605 -6.5% 102455 perf-stat.i.cpu-migrations
7.944e+10 -5.3% 7.525e+10 perf-stat.i.instructions
0.80 -3.9% 0.77 perf-stat.i.ipc
13.83 -4.2% 13.25 perf-stat.i.metric.K/sec
2.53 +1.1% 2.56 perf-stat.overall.MPKI
0.36 +0.0 0.38 perf-stat.overall.branch-miss-rate%
55.07 -1.1 54.02 perf-stat.overall.cache-miss-rate%
1.23 +2.4% 1.26 perf-stat.overall.cpi
0.81 -2.3% 0.79 perf-stat.overall.ipc
1.674e+10 -4.8% 1.593e+10 perf-stat.ps.branch-instructions
1.983e+08 -4.0% 1.903e+08 perf-stat.ps.cache-misses
3.601e+08 -2.1% 3.523e+08 perf-stat.ps.cache-references
779885 -3.7% 751092 perf-stat.ps.context-switches
9.668e+10 -2.8% 9.396e+10 perf-stat.ps.cpu-cycles
108710 -6.4% 101802 perf-stat.ps.cpu-migrations
7.844e+10 -5.1% 7.447e+10 perf-stat.ps.instructions
31.16 -0.6 30.61 perf-profile.calltrace.cycles-pp.__x64_sys_openat.do_syscall_64.entry_SYSCALL_64_after_hwframe
31.02 -0.5 30.48 perf-profile.calltrace.cycles-pp.do_sys_openat2.__x64_sys_openat.do_syscall_64.entry_SYSCALL_64_after_hwframe
28.00 -0.5 27.50 perf-profile.calltrace.cycles-pp.do_file_open.do_sys_openat2.__x64_sys_openat.do_syscall_64.entry_SYSCALL_64_after_hwframe
27.72 -0.5 27.22 perf-profile.calltrace.cycles-pp.path_openat.do_file_open.do_sys_openat2.__x64_sys_openat.do_syscall_64
8.96 -0.5 8.49 perf-profile.calltrace.cycles-pp.asm_sysvec_call_function_single.pv_native_safe_halt.acpi_safe_halt.acpi_idle_do_entry.acpi_idle_enter
9.75 -0.3 9.48 perf-profile.calltrace.cycles-pp.__btrfs_unlink_inode.btrfs_rename.btrfs_rename2.vfs_rename.filename_renameat2
1.72 -0.1 1.64 perf-profile.calltrace.cycles-pp.sysvec_call_function_single.asm_sysvec_call_function_single.pv_native_safe_halt.acpi_safe_halt.acpi_idle_do_entry
1.75 -0.1 1.67 ± 2% perf-profile.calltrace.cycles-pp.__start_renaming.filename_renameat2.__x64_sys_rename.do_syscall_64.entry_SYSCALL_64_after_hwframe
0.78 ± 3% -0.1 0.72 ± 4% perf-profile.calltrace.cycles-pp.path_init.path_openat.do_file_open.do_sys_openat2.__x64_sys_openat
1.46 -0.1 1.40 perf-profile.calltrace.cycles-pp.btrfs_add_link.btrfs_rename.btrfs_rename2.vfs_rename.filename_renameat2
0.82 ± 3% -0.1 0.76 perf-profile.calltrace.cycles-pp.btrfs_lock_root_node.btrfs_search_slot.btrfs_delete_delayed_items.btrfs_async_run_delayed_root.btrfs_work_helper
0.82 ± 3% -0.1 0.76 ± 2% perf-profile.calltrace.cycles-pp.btrfs_tree_lock_nested.btrfs_lock_root_node.btrfs_search_slot.btrfs_delete_delayed_items.btrfs_async_run_delayed_root
0.82 ± 3% -0.1 0.76 ± 2% perf-profile.calltrace.cycles-pp.down_write.btrfs_tree_lock_nested.btrfs_lock_root_node.btrfs_search_slot.btrfs_delete_delayed_items
1.35 -0.1 1.29 perf-profile.calltrace.cycles-pp.__sysvec_call_function_single.sysvec_call_function_single.asm_sysvec_call_function_single.pv_native_safe_halt.acpi_safe_halt
1.26 -0.1 1.21 perf-profile.calltrace.cycles-pp.__flush_smp_call_function_queue.__sysvec_call_function_single.sysvec_call_function_single.asm_sysvec_call_function_single.pv_native_safe_halt
0.90 -0.0 0.86 perf-profile.calltrace.cycles-pp.sched_ttwu_pending.__flush_smp_call_function_queue.__sysvec_call_function_single.sysvec_call_function_single.asm_sysvec_call_function_single
0.63 -0.0 0.60 perf-profile.calltrace.cycles-pp.ttwu_do_activate.sched_ttwu_pending.__flush_smp_call_function_queue.__sysvec_call_function_single.sysvec_call_function_single
0.75 -0.0 0.73 perf-profile.calltrace.cycles-pp.__schedule.schedule_idle.do_idle.cpu_startup_entry.start_secondary
0.56 -0.0 0.54 ± 2% perf-profile.calltrace.cycles-pp.down_write.__start_renaming.filename_renameat2.__x64_sys_rename.do_syscall_64
0.77 -0.0 0.75 perf-profile.calltrace.cycles-pp.schedule_idle.do_idle.cpu_startup_entry.start_secondary.common_startup_64
0.66 ± 5% +0.1 0.74 ± 5% perf-profile.calltrace.cycles-pp.btrfs_read_lock_root_node.btrfs_search_slot.btrfs_lookup_inode.__btrfs_update_delayed_inode.btrfs_async_run_delayed_root
0.64 ± 4% +0.1 0.72 ± 5% perf-profile.calltrace.cycles-pp.down_read.btrfs_tree_read_lock_nested.btrfs_read_lock_root_node.btrfs_search_slot.btrfs_lookup_inode
0.64 ± 4% +0.1 0.72 ± 5% perf-profile.calltrace.cycles-pp.btrfs_tree_read_lock_nested.btrfs_read_lock_root_node.btrfs_search_slot.btrfs_lookup_inode.__btrfs_update_delayed_inode
2.77 +0.1 2.91 perf-profile.calltrace.cycles-pp.pv_native_safe_halt.acpi_safe_halt.acpi_idle_do_entry.acpi_idle_enter.cpuidle_enter_state
1.12 ± 3% +0.2 1.34 ± 4% perf-profile.calltrace.cycles-pp.__btrfs_update_delayed_inode.btrfs_async_run_delayed_root.btrfs_work_helper.process_one_work.worker_thread
1.02 ± 3% +0.2 1.25 ± 4% perf-profile.calltrace.cycles-pp.btrfs_lookup_inode.__btrfs_update_delayed_inode.btrfs_async_run_delayed_root.btrfs_work_helper.process_one_work
1.02 ± 3% +0.2 1.25 ± 4% perf-profile.calltrace.cycles-pp.btrfs_search_slot.btrfs_lookup_inode.__btrfs_update_delayed_inode.btrfs_async_run_delayed_root.btrfs_work_helper
0.66 +0.3 0.92 ± 2% perf-profile.calltrace.cycles-pp.asm_sysvec_apic_timer_interrupt.pv_native_safe_halt.acpi_safe_halt.acpi_idle_do_entry.acpi_idle_enter
3.16 ± 2% +0.5 3.68 ± 2% perf-profile.calltrace.cycles-pp.btrfs_work_helper.process_one_work.worker_thread.kthread.ret_from_fork
3.15 ± 2% +0.5 3.68 ± 2% perf-profile.calltrace.cycles-pp.btrfs_async_run_delayed_root.btrfs_work_helper.process_one_work.worker_thread.kthread
0.00 +0.5 0.54 ± 3% perf-profile.calltrace.cycles-pp.__btrfs_end_transaction.btrfs_rename.btrfs_rename2.vfs_rename.filename_renameat2
3.30 ± 2% +0.6 3.88 ± 2% perf-profile.calltrace.cycles-pp.process_one_work.worker_thread.kthread.ret_from_fork.ret_from_fork_asm
3.31 ± 3% +0.6 3.89 ± 2% perf-profile.calltrace.cycles-pp.worker_thread.kthread.ret_from_fork.ret_from_fork_asm
3.32 ± 3% +0.7 3.98 ± 2% perf-profile.calltrace.cycles-pp.kthread.ret_from_fork.ret_from_fork_asm
3.32 ± 3% +0.7 3.98 ± 2% perf-profile.calltrace.cycles-pp.ret_from_fork.ret_from_fork_asm
3.32 ± 3% +0.7 3.98 ± 2% perf-profile.calltrace.cycles-pp.ret_from_fork_asm
0.00 +0.7 0.66 ± 3% perf-profile.calltrace.cycles-pp.sysvec_apic_timer_interrupt.asm_sysvec_apic_timer_interrupt.pv_native_safe_halt.acpi_safe_halt.acpi_idle_do_entry
31.22 -0.6 30.67 perf-profile.children.cycles-pp.__x64_sys_openat
31.13 -0.5 30.59 perf-profile.children.cycles-pp.do_sys_openat2
28.06 -0.5 27.56 perf-profile.children.cycles-pp.do_file_open
27.86 -0.5 27.36 perf-profile.children.cycles-pp.path_openat
76.72 -0.5 76.23 perf-profile.children.cycles-pp.entry_SYSCALL_64_after_hwframe
76.28 -0.5 75.80 perf-profile.children.cycles-pp.do_syscall_64
7.38 ± 2% -0.4 7.03 ± 2% perf-profile.children.cycles-pp.rwsem_down_write_slowpath
8.19 ± 2% -0.3 7.86 ± 2% perf-profile.children.cycles-pp.down_write
6.71 ± 2% -0.3 6.42 ± 3% perf-profile.children.cycles-pp.btrfs_tree_lock_nested
5.49 -0.3 5.21 perf-profile.children.cycles-pp.asm_sysvec_call_function_single
9.75 -0.3 9.48 perf-profile.children.cycles-pp.__btrfs_unlink_inode
1.77 -0.1 1.69 perf-profile.children.cycles-pp.sysvec_call_function_single
0.88 -0.1 0.81 ± 2% perf-profile.children.cycles-pp.__memmove
1.84 -0.1 1.76 perf-profile.children.cycles-pp.rwsem_wake
1.75 -0.1 1.67 ± 2% perf-profile.children.cycles-pp.__start_renaming
1.60 -0.1 1.52 perf-profile.children.cycles-pp.wake_up_q
0.82 ± 2% -0.1 0.75 ± 3% perf-profile.children.cycles-pp.path_init
1.88 -0.1 1.81 perf-profile.children.cycles-pp.up_write
1.46 -0.1 1.40 perf-profile.children.cycles-pp.btrfs_add_link
1.55 -0.1 1.49 perf-profile.children.cycles-pp.try_to_wake_up
1.39 -0.1 1.33 perf-profile.children.cycles-pp.__sysvec_call_function_single
1.31 -0.1 1.26 perf-profile.children.cycles-pp.__flush_smp_call_function_queue
0.62 -0.0 0.57 perf-profile.children.cycles-pp.btrfs_update_inode
0.44 -0.0 0.40 ± 3% perf-profile.children.cycles-pp.btrfs_extend_item
0.47 -0.0 0.43 ± 3% perf-profile.children.cycles-pp.setup_items_for_insert
0.93 -0.0 0.90 perf-profile.children.cycles-pp.sched_ttwu_pending
0.50 -0.0 0.46 perf-profile.children.cycles-pp.btrfs_delayed_update_inode
1.29 -0.0 1.26 perf-profile.children.cycles-pp.inode_permission
0.31 ± 3% -0.0 0.28 ± 3% perf-profile.children.cycles-pp._raw_spin_lock_irqsave
0.13 ± 4% -0.0 0.11 ± 3% perf-profile.children.cycles-pp.__btrfs_release_delayed_node
0.19 -0.0 0.17 ± 3% perf-profile.children.cycles-pp.btrfs_readdir_get_delayed_items
0.16 -0.0 0.14 ± 5% perf-profile.children.cycles-pp.btrfs_inode_lock
0.22 ± 2% -0.0 0.21 ± 2% perf-profile.children.cycles-pp.wakeup_preempt
0.10 ± 5% -0.0 0.08 ± 4% perf-profile.children.cycles-pp.btrfs_update_root_times
0.00 +0.1 0.05 ± 8% perf-profile.children.cycles-pp.radix_tree_node_rcu_free
0.00 +0.1 0.06 ± 6% perf-profile.children.cycles-pp.__call_rcu_common
0.01 ±223% +0.1 0.07 ± 8% perf-profile.children.cycles-pp.__slab_free
0.02 ± 99% +0.1 0.10 ± 8% perf-profile.children.cycles-pp._raw_spin_unlock_irq
0.00 +0.1 0.07 ± 9% perf-profile.children.cycles-pp.run_ksoftirqd
0.00 +0.1 0.08 ± 8% perf-profile.children.cycles-pp.smpboot_thread_fn
0.00 +0.1 0.08 ± 7% perf-profile.children.cycles-pp.rcu_cblist_dequeue
0.00 +0.1 0.08 ± 5% perf-profile.children.cycles-pp.__refill_objects_node
0.00 +0.1 0.09 ± 4% perf-profile.children.cycles-pp.refill_objects
0.00 +0.1 0.10 ± 5% perf-profile.children.cycles-pp.__pcs_replace_empty_main
0.00 +0.1 0.10 ± 3% perf-profile.children.cycles-pp.xas_alloc
0.00 +0.1 0.11 ± 4% perf-profile.children.cycles-pp.kmem_cache_alloc_lru_noprof
0.20 +0.1 0.32 ± 4% perf-profile.children.cycles-pp.xa_load
0.19 +0.1 0.32 ± 4% perf-profile.children.cycles-pp.xas_load
0.54 +0.1 0.67 ± 2% perf-profile.children.cycles-pp.__memcg_slab_free_hook
0.00 +0.2 0.19 ± 3% perf-profile.children.cycles-pp.xas_create
0.00 +0.2 0.21 ± 5% perf-profile.children.cycles-pp.xas_store
0.00 +0.2 0.22 ± 3% perf-profile.children.cycles-pp.__xa_store
1.12 ± 3% +0.2 1.34 ± 4% perf-profile.children.cycles-pp.__btrfs_update_delayed_inode
0.00 +0.2 0.23 ± 3% perf-profile.children.cycles-pp.xa_store
1.02 ± 3% +0.2 1.25 ± 4% perf-profile.children.cycles-pp.btrfs_lookup_inode
0.00 +0.3 0.25 ± 3% perf-profile.children.cycles-pp.xas_free_nodes
0.00 +0.3 0.26 ± 3% perf-profile.children.cycles-pp.xa_destroy
1.06 +0.3 1.39 perf-profile.children.cycles-pp.kmem_cache_free
0.00 +0.4 0.38 ± 5% perf-profile.children.cycles-pp.xa_find_after
0.00 +0.4 0.43 ± 5% perf-profile.children.cycles-pp.xas_find
0.23 ± 3% +0.5 0.70 ± 3% perf-profile.children.cycles-pp.__irq_exit_rcu
0.72 ± 2% +0.5 1.19 perf-profile.children.cycles-pp.sysvec_apic_timer_interrupt
1.02 +0.5 1.49 perf-profile.children.cycles-pp.asm_sysvec_apic_timer_interrupt
0.00 +0.5 0.50 ± 4% perf-profile.children.cycles-pp.btrfs_inhibit_eb_writeback
0.05 +0.5 0.58 ± 4% perf-profile.children.cycles-pp.rcu_do_batch
3.16 ± 2% +0.5 3.68 ± 2% perf-profile.children.cycles-pp.btrfs_work_helper
3.15 +0.5 3.68 ± 2% perf-profile.children.cycles-pp.btrfs_async_run_delayed_root
0.09 +0.5 0.62 ± 4% perf-profile.children.cycles-pp.rcu_core
0.18 ± 2% +0.5 0.72 ± 3% perf-profile.children.cycles-pp.handle_softirqs
3.30 ± 2% +0.6 3.88 ± 2% perf-profile.children.cycles-pp.process_one_work
3.31 ± 3% +0.6 3.89 ± 2% perf-profile.children.cycles-pp.worker_thread
3.32 ± 3% +0.7 3.98 ± 2% perf-profile.children.cycles-pp.kthread
3.32 ± 3% +0.7 3.98 ± 2% perf-profile.children.cycles-pp.ret_from_fork
3.32 ± 3% +0.7 3.98 ± 2% perf-profile.children.cycles-pp.ret_from_fork_asm
0.00 +0.8 0.79 ± 2% perf-profile.children.cycles-pp.btrfs_uninhibit_all_eb_writeback
0.07 ± 5% +0.8 0.87 ± 2% perf-profile.children.cycles-pp.__btrfs_end_transaction
4.33 -0.2 4.11 perf-profile.self.cycles-pp.pv_native_safe_halt
0.48 ± 18% -0.1 0.39 ± 4% perf-profile.self.cycles-pp.rwsem_down_write_slowpath
0.88 -0.1 0.80 ± 3% perf-profile.self.cycles-pp.__memmove
0.79 ± 3% -0.1 0.72 ± 4% perf-profile.self.cycles-pp.path_init
2.26 -0.0 2.23 perf-profile.self.cycles-pp.clear_bhb_loop
0.13 -0.0 0.12 ± 4% perf-profile.self.cycles-pp.poll_idle
0.20 -0.0 0.19 perf-profile.self.cycles-pp.__flush_smp_call_function_queue
0.20 ± 2% -0.0 0.19 ± 3% perf-profile.self.cycles-pp.__resched_curr
0.00 +0.1 0.06 ± 9% perf-profile.self.cycles-pp.rcu_do_batch
0.00 +0.1 0.06 ± 14% perf-profile.self.cycles-pp.btrfs_uninhibit_all_eb_writeback
0.00 +0.1 0.06 ± 7% perf-profile.self.cycles-pp.__slab_free
0.00 +0.1 0.08 ± 4% perf-profile.self.cycles-pp.__refill_objects_node
0.00 +0.1 0.08 ± 4% perf-profile.self.cycles-pp.rcu_cblist_dequeue
0.00 +0.1 0.09 ± 4% perf-profile.self.cycles-pp.xas_create
0.14 ± 3% +0.1 0.25 ± 4% perf-profile.self.cycles-pp.xas_load
0.24 ± 4% +0.1 0.37 ± 3% perf-profile.self.cycles-pp.__memcg_slab_free_hook
0.00 +0.1 0.14 ± 15% perf-profile.self.cycles-pp.btrfs_inhibit_eb_writeback
0.47 ± 2% +0.2 0.63 ± 2% perf-profile.self.cycles-pp.kmem_cache_free
0.00 +0.2 0.20 ± 4% perf-profile.self.cycles-pp.xas_free_nodes
0.00 +0.4 0.42 ± 4% perf-profile.self.cycles-pp.xas_find

***************************************************************************************************

=========================================================================================
compiler/cpufreq_governor/disk/filesize/fs/iterations/kconfig/nr_files_per_directory/nr_threads/rootfs/sync_method/tbox_group/test_size/testcase:
gcc-14/performance/1BRD_32G/4K/btrfs/1x/x86_64-rhel-9.4/1fpd/1t/debian-13-x86_64-20250902.cgz/fsyncBeforeClose/lkp-icl-2sp9/4G/fsmark

commit:
ed7bc52711 ("btrfs: extract the max compression chunk size into a macro")
f9d138838a ("btrfs: inhibit extent buffer writeback to prevent COW amplification")

ed7bc52711022142 f9d138838a78bf2a5263ad3c1d3
---------------- ---------------------------
%stddev %change %stddev
\ | \
18435752 +18.4% 21820507 fsmark.app_overhead
6483 -6.5% 6059 fsmark.files_per_sec
158.16 +6.7% 168.82 fsmark.time.elapsed_time
158.16 +6.7% 168.82 fsmark.time.elapsed_time.max
81.50 -4.3% 78.00 fsmark.time.percent_of_cpu_this_job_got
3081153 +1.6% 3131359 fsmark.time.voluntary_context_switches
9.99e+09 +6.8% 1.067e+10 cpuidle..time
2350 ± 4% -15.4% 1988 ± 2% perf-c2c.HITM.local
205.55 +5.2% 216.26 uptime.boot
12643 +5.3% 13314 uptime.idle
0.05 -0.0 0.05 mpstat.cpu.all.iowait%
0.03 ± 6% +0.0 0.05 mpstat.cpu.all.soft%
0.37 -0.0 0.35 ± 2% mpstat.cpu.all.usr%
978289 -6.1% 918444 vmstat.io.bo
183913 -6.3% 172244 vmstat.system.cs
99177 -5.4% 93816 vmstat.system.in
1.581e+09 +3.7% 1.64e+09 perf-stat.i.branch-instructions
0.91 -0.0 0.86 perf-stat.i.branch-miss-rate%
19.12 -0.2 18.88 perf-stat.i.cache-miss-rate%
12573211 +4.2% 13106119 perf-stat.i.cache-misses
67064028 +5.6% 70830932 perf-stat.i.cache-references
187480 -6.7% 174988 perf-stat.i.context-switches
0.82 -3.9% 0.79 perf-stat.i.cpi
7.006e+09 -2.2% 6.854e+09 perf-stat.i.cpu-cycles
108.44 +21.8% 132.09 ± 2% perf-stat.i.cpu-migrations
571.12 -6.5% 534.23 perf-stat.i.cycles-between-cache-misses
1.26 +3.7% 1.31 perf-stat.i.ipc
2.92 -6.7% 2.73 perf-stat.i.metric.K/sec
1.46 +2.8% 1.50 perf-stat.overall.MPKI
1.20 -0.1 1.13 perf-stat.overall.branch-miss-rate%
0.81 -3.5% 0.78 perf-stat.overall.cpi
557.39 -6.1% 523.26 perf-stat.overall.cycles-between-cache-misses
1.23 +3.6% 1.28 perf-stat.overall.ipc
1.572e+09 +3.7% 1.63e+09 perf-stat.ps.branch-instructions
12495446 +4.3% 13029250 perf-stat.ps.cache-misses
66647875 +5.7% 70420075 perf-stat.ps.cache-references
186297 -6.6% 173960 perf-stat.ps.context-switches
6.965e+09 -2.1% 6.817e+09 perf-stat.ps.cpu-cycles
107.77 +21.9% 131.32 ± 2% perf-stat.ps.cpu-migrations
1.37e+12 +8.3% 1.485e+12 perf-stat.total.instructions
27.32 ± 3% -1.4 25.94 ± 2% perf-profile.calltrace.cycles-pp.btrfs_sync_file.do_fsync.__x64_sys_fsync.do_syscall_64.entry_SYSCALL_64_after_hwframe
27.34 ± 3% -1.4 25.96 ± 2% perf-profile.calltrace.cycles-pp.__x64_sys_fsync.do_syscall_64.entry_SYSCALL_64_after_hwframe
27.34 ± 3% -1.4 25.96 ± 2% perf-profile.calltrace.cycles-pp.do_fsync.__x64_sys_fsync.do_syscall_64.entry_SYSCALL_64_after_hwframe
16.88 ± 2% -1.3 15.58 ± 2% perf-profile.calltrace.cycles-pp.btrfs_sync_log.btrfs_sync_file.do_fsync.__x64_sys_fsync.do_syscall_64
13.40 ± 3% -0.9 12.52 ± 2% perf-profile.calltrace.cycles-pp.btrfs_submit_chunk.btrfs_submit_bbio.btree_writepages.do_writepages.filemap_writeback
13.40 ± 3% -0.9 12.52 ± 2% perf-profile.calltrace.cycles-pp.btrfs_submit_bbio.btree_writepages.do_writepages.filemap_writeback.btrfs_write_marked_extents
5.17 ± 17% -0.8 4.36 ± 2% perf-profile.calltrace.cycles-pp.btrfs_submit_bio.btrfs_submit_chunk.btrfs_submit_bbio.btree_writepages.do_writepages
4.90 ± 18% -0.8 4.12 ± 2% perf-profile.calltrace.cycles-pp.__submit_bio_noacct.btrfs_submit_bio.btrfs_submit_chunk.btrfs_submit_bbio.btree_writepages
4.89 ± 18% -0.8 4.11 ± 2% perf-profile.calltrace.cycles-pp.__submit_bio.__submit_bio_noacct.btrfs_submit_bio.btrfs_submit_chunk.btrfs_submit_bbio
4.16 ± 19% -0.7 3.50 ± 2% perf-profile.calltrace.cycles-pp.brd_submit_bio.__submit_bio.__submit_bio_noacct.btrfs_submit_bio.btrfs_submit_chunk
12.36 ± 3% -0.6 11.73 ± 2% perf-profile.calltrace.cycles-pp.filemap_writeback.btrfs_write_marked_extents.btrfs_sync_log.btrfs_sync_file.do_fsync
12.48 ± 3% -0.6 11.85 ± 2% perf-profile.calltrace.cycles-pp.btrfs_write_marked_extents.btrfs_sync_log.btrfs_sync_file.do_fsync.__x64_sys_fsync
12.31 ± 3% -0.6 11.68 ± 2% perf-profile.calltrace.cycles-pp.do_writepages.filemap_writeback.btrfs_write_marked_extents.btrfs_sync_log.btrfs_sync_file
12.30 ± 3% -0.6 11.67 ± 2% perf-profile.calltrace.cycles-pp.btree_writepages.do_writepages.filemap_writeback.btrfs_write_marked_extents.btrfs_sync_log
1.93 ± 10% -0.6 1.33 ± 11% perf-profile.calltrace.cycles-pp.mutex_spin_on_owner.__mutex_lock.btrfs_sync_log.btrfs_sync_file.do_fsync
1.93 ± 10% -0.6 1.34 ± 11% perf-profile.calltrace.cycles-pp.__mutex_lock.btrfs_sync_log.btrfs_sync_file.do_fsync.__x64_sys_fsync
4.54 ± 3% -0.5 4.08 ± 2% perf-profile.calltrace.cycles-pp.btrfs_preempt_reclaim_metadata_space.process_one_work.worker_thread.kthread.ret_from_fork
4.54 ± 3% -0.5 4.08 ± 2% perf-profile.calltrace.cycles-pp.flush_space.btrfs_preempt_reclaim_metadata_space.process_one_work.worker_thread.kthread
3.29 ± 3% -0.4 2.88 ± 2% perf-profile.calltrace.cycles-pp.btrfs_commit_transaction.flush_space.btrfs_preempt_reclaim_metadata_space.process_one_work.worker_thread
2.83 ± 2% -0.3 2.50 ± 3% perf-profile.calltrace.cycles-pp.filemap_writeback.btrfs_write_marked_extents.btrfs_write_and_wait_transaction.btrfs_commit_transaction.flush_space
2.82 ± 2% -0.3 2.49 ± 3% perf-profile.calltrace.cycles-pp.btree_writepages.do_writepages.filemap_writeback.btrfs_write_marked_extents.btrfs_write_and_wait_transaction
2.82 ± 2% -0.3 2.49 ± 3% perf-profile.calltrace.cycles-pp.do_writepages.filemap_writeback.btrfs_write_marked_extents.btrfs_write_and_wait_transaction.btrfs_commit_transaction
2.85 ± 2% -0.3 2.52 ± 3% perf-profile.calltrace.cycles-pp.btrfs_write_marked_extents.btrfs_write_and_wait_transaction.btrfs_commit_transaction.flush_space.btrfs_preempt_reclaim_metadata_space
2.86 ± 2% -0.3 2.54 ± 3% perf-profile.calltrace.cycles-pp.btrfs_write_and_wait_transaction.btrfs_commit_transaction.flush_space.btrfs_preempt_reclaim_metadata_space.process_one_work
1.13 ± 18% -0.3 0.82 ± 24% perf-profile.calltrace.cycles-pp.btrfs_init_new_buffer.btrfs_alloc_tree_block.btrfs_force_cow_block.btrfs_cow_block.btrfs_search_slot
0.94 ± 19% -0.2 0.76 ± 4% perf-profile.calltrace.cycles-pp.copy_extent_buffer_full.btrfs_force_cow_block.btrfs_cow_block.btrfs_search_slot.btrfs_lookup_csum
1.54 ± 3% -0.1 1.43 ± 4% perf-profile.calltrace.cycles-pp.orig_write_end_io_work.process_one_work.worker_thread.kthread.ret_from_fork
1.64 ± 2% -0.1 1.56 perf-profile.calltrace.cycles-pp.btrfs_cow_block.btrfs_search_slot.btrfs_update_root.btrfs_sync_log.btrfs_sync_file
1.63 ± 2% -0.1 1.56 perf-profile.calltrace.cycles-pp.btrfs_force_cow_block.btrfs_cow_block.btrfs_search_slot.btrfs_update_root.btrfs_sync_log
1.67 ± 2% -0.1 1.60 perf-profile.calltrace.cycles-pp.btrfs_search_slot.btrfs_update_root.btrfs_sync_log.btrfs_sync_file.do_fsync
1.69 ± 2% -0.1 1.63 perf-profile.calltrace.cycles-pp.btrfs_update_root.btrfs_sync_log.btrfs_sync_file.do_fsync.__x64_sys_fsync
1.00 ± 5% +0.1 1.08 ± 3% perf-profile.calltrace.cycles-pp.btrfs_create_new_inode.btrfs_create_common.lookup_open.open_last_lookups.path_openat
0.78 ± 7% +0.1 0.87 ± 2% perf-profile.calltrace.cycles-pp.insert_reserved_file_extent.btrfs_finish_one_ordered.btrfs_work_helper.process_one_work.worker_thread
0.56 ± 3% +0.2 0.76 ± 4% perf-profile.calltrace.cycles-pp.btrfs_insert_delayed_item.btrfs_async_run_delayed_root.btrfs_work_helper.process_one_work.worker_thread
1.59 ± 6% +0.4 1.98 ± 2% perf-profile.calltrace.cycles-pp.lookup_open.open_last_lookups.path_openat.do_file_open.do_sys_openat2
1.65 ± 5% +0.4 2.06 ± 2% perf-profile.calltrace.cycles-pp.open_last_lookups.path_openat.do_file_open.do_sys_openat2.__x64_sys_openat
1.85 ± 5% +0.4 2.26 ± 3% perf-profile.calltrace.cycles-pp.path_openat.do_file_open.do_sys_openat2.__x64_sys_openat.do_syscall_64
1.85 ± 5% +0.4 2.26 ± 3% perf-profile.calltrace.cycles-pp.do_file_open.do_sys_openat2.__x64_sys_openat.do_syscall_64.entry_SYSCALL_64_after_hwframe
1.90 ± 5% +0.4 2.32 ± 3% perf-profile.calltrace.cycles-pp.__x64_sys_openat.do_syscall_64.entry_SYSCALL_64_after_hwframe
1.90 ± 5% +0.4 2.32 ± 3% perf-profile.calltrace.cycles-pp.do_sys_openat2.__x64_sys_openat.do_syscall_64.entry_SYSCALL_64_after_hwframe
1.13 ± 6% +0.4 1.57 ± 4% perf-profile.calltrace.cycles-pp.btrfs_create_common.lookup_open.open_last_lookups.path_openat.do_file_open
2.15 ± 4% +0.5 2.67 perf-profile.calltrace.cycles-pp.btrfs_finish_one_ordered.btrfs_work_helper.process_one_work.worker_thread.kthread
3.88 ± 4% +0.5 4.40 ± 2% perf-profile.calltrace.cycles-pp.pv_native_safe_halt.acpi_safe_halt.acpi_idle_do_entry.acpi_idle_enter.cpuidle_enter_state
0.00 +0.5 0.52 ± 4% perf-profile.calltrace.cycles-pp.__btrfs_end_transaction.btrfs_create_common.btrfs_mkdir.vfs_mkdir.filename_mkdirat
3.58 ± 4% +0.5 4.13 ± 2% perf-profile.calltrace.cycles-pp.filename_mkdirat.__x64_sys_mkdir.do_syscall_64.entry_SYSCALL_64_after_hwframe.mkdir
3.62 ± 5% +0.5 4.17 ± 2% perf-profile.calltrace.cycles-pp.__x64_sys_mkdir.do_syscall_64.entry_SYSCALL_64_after_hwframe.mkdir
3.63 ± 5% +0.6 4.18 ± 2% perf-profile.calltrace.cycles-pp.entry_SYSCALL_64_after_hwframe.mkdir
2.76 ± 5% +0.6 3.31 perf-profile.calltrace.cycles-pp.btrfs_create_common.btrfs_mkdir.vfs_mkdir.filename_mkdirat.__x64_sys_mkdir
3.63 ± 5% +0.6 4.18 ± 2% perf-profile.calltrace.cycles-pp.do_syscall_64.entry_SYSCALL_64_after_hwframe.mkdir
3.65 ± 4% +0.6 4.21 ± 2% perf-profile.calltrace.cycles-pp.mkdir
2.95 ± 5% +0.6 3.51 ± 2% perf-profile.calltrace.cycles-pp.btrfs_mkdir.vfs_mkdir.filename_mkdirat.__x64_sys_mkdir.do_syscall_64
2.99 ± 5% +0.6 3.55 ± 2% perf-profile.calltrace.cycles-pp.vfs_mkdir.filename_mkdirat.__x64_sys_mkdir.do_syscall_64.entry_SYSCALL_64_after_hwframe
0.00 +0.6 0.56 ± 3% perf-profile.calltrace.cycles-pp.btrfs_drop_extents.insert_reserved_file_extent.btrfs_finish_one_ordered.btrfs_work_helper.process_one_work
0.00 +0.6 0.60 ± 5% perf-profile.calltrace.cycles-pp.__btrfs_update_delayed_inode.btrfs_async_run_delayed_root.btrfs_work_helper.process_one_work.worker_thread
0.00 +0.6 0.63 ± 6% perf-profile.calltrace.cycles-pp.rcu_do_batch.rcu_core.handle_softirqs.__irq_exit_rcu.sysvec_apic_timer_interrupt
0.00 +0.6 0.65 ± 6% perf-profile.calltrace.cycles-pp.rcu_core.handle_softirqs.__irq_exit_rcu.sysvec_apic_timer_interrupt.asm_sysvec_apic_timer_interrupt
0.00 +0.7 0.67 ± 5% perf-profile.calltrace.cycles-pp.btrfs_insert_empty_items.btrfs_insert_delayed_item.btrfs_async_run_delayed_root.btrfs_work_helper.process_one_work
0.00 +0.7 0.70 ± 4% perf-profile.calltrace.cycles-pp.btrfs_uninhibit_all_eb_writeback.__btrfs_end_transaction.btrfs_async_run_delayed_root.btrfs_work_helper.process_one_work
0.00 +0.7 0.70 ± 6% perf-profile.calltrace.cycles-pp.handle_softirqs.__irq_exit_rcu.sysvec_apic_timer_interrupt.asm_sysvec_apic_timer_interrupt.pv_native_safe_halt
0.00 +0.7 0.70 ± 7% perf-profile.calltrace.cycles-pp.__irq_exit_rcu.sysvec_apic_timer_interrupt.asm_sysvec_apic_timer_interrupt.pv_native_safe_halt.acpi_safe_halt
0.00 +0.7 0.72 ± 4% perf-profile.calltrace.cycles-pp.__btrfs_end_transaction.btrfs_async_run_delayed_root.btrfs_work_helper.process_one_work.worker_thread
0.47 ± 44% +0.8 1.25 ± 4% perf-profile.calltrace.cycles-pp.asm_sysvec_apic_timer_interrupt.pv_native_safe_halt.acpi_safe_halt.acpi_idle_do_entry.acpi_idle_enter
32.62 +0.9 33.48 ± 2% perf-profile.calltrace.cycles-pp.kthread.ret_from_fork.ret_from_fork_asm
32.62 +0.9 33.48 ± 2% perf-profile.calltrace.cycles-pp.ret_from_fork.ret_from_fork_asm
32.62 +0.9 33.48 ± 2% perf-profile.calltrace.cycles-pp.ret_from_fork_asm
0.00 +0.9 0.93 ± 5% perf-profile.calltrace.cycles-pp.sysvec_apic_timer_interrupt.asm_sysvec_apic_timer_interrupt.pv_native_safe_halt.acpi_safe_halt.acpi_idle_do_entry
1.11 ± 2% +1.1 2.21 ± 3% perf-profile.calltrace.cycles-pp.btrfs_async_run_delayed_root.btrfs_work_helper.process_one_work.worker_thread.kthread
3.27 ± 3% +1.6 4.89 perf-profile.calltrace.cycles-pp.btrfs_work_helper.process_one_work.worker_thread.kthread.ret_from_fork
27.33 ± 3% -1.4 25.94 ± 2% perf-profile.children.cycles-pp.btrfs_sync_file
27.34 ± 3% -1.4 25.96 ± 2% perf-profile.children.cycles-pp.__x64_sys_fsync
27.34 ± 3% -1.4 25.96 ± 2% perf-profile.children.cycles-pp.do_fsync
16.89 ± 2% -1.3 15.58 ± 2% perf-profile.children.cycles-pp.btrfs_sync_log
16.57 ± 2% -1.0 15.60 ± 2% perf-profile.children.cycles-pp.filemap_writeback
16.46 ± 2% -1.0 15.49 ± 2% perf-profile.children.cycles-pp.do_writepages
15.34 ± 3% -1.0 14.38 ± 2% perf-profile.children.cycles-pp.btrfs_write_marked_extents
15.13 ± 3% -1.0 14.17 ± 2% perf-profile.children.cycles-pp.btree_writepages
13.82 ± 3% -0.9 12.96 ± 2% perf-profile.children.cycles-pp.btrfs_submit_chunk
13.83 ± 3% -0.9 12.96 ± 2% perf-profile.children.cycles-pp.btrfs_submit_bbio
5.50 ± 12% -0.7 4.81 ± 2% perf-profile.children.cycles-pp.btrfs_submit_bio
5.52 ± 12% -0.7 4.86 perf-profile.children.cycles-pp.__submit_bio_noacct
5.50 ± 12% -0.7 4.84 perf-profile.children.cycles-pp.__submit_bio
1.93 ± 10% -0.6 1.34 ± 10% perf-profile.children.cycles-pp.mutex_spin_on_owner
1.93 ± 10% -0.6 1.34 ± 11% perf-profile.children.cycles-pp.__mutex_lock
4.54 ± 13% -0.6 3.96 ± 2% perf-profile.children.cycles-pp.brd_rw_bvec
4.56 ± 13% -0.6 3.98 ± 2% perf-profile.children.cycles-pp.brd_submit_bio
6.48 ± 7% -0.5 5.97 perf-profile.children.cycles-pp.btrfs_force_cow_block
6.49 ± 7% -0.5 6.00 perf-profile.children.cycles-pp.btrfs_cow_block
4.54 ± 3% -0.5 4.08 ± 2% perf-profile.children.cycles-pp.btrfs_preempt_reclaim_metadata_space
4.54 ± 3% -0.5 4.08 ± 2% perf-profile.children.cycles-pp.flush_space
3.29 ± 3% -0.4 2.88 ± 2% perf-profile.children.cycles-pp.btrfs_commit_transaction
3.28 ± 9% -0.4 2.92 ± 2% perf-profile.children.cycles-pp.__pi_memcpy
2.86 ± 2% -0.3 2.54 ± 3% perf-profile.children.cycles-pp.btrfs_write_and_wait_transaction
2.19 ± 15% -0.3 1.88 ± 2% perf-profile.children.cycles-pp.copy_extent_buffer_full
2.66 ± 2% -0.2 2.46 ± 2% perf-profile.children.cycles-pp.btrfs_alloc_tree_block
1.82 ± 3% -0.1 1.68 ± 2% perf-profile.children.cycles-pp.btrfs_init_new_buffer
1.54 ± 3% -0.1 1.43 ± 4% perf-profile.children.cycles-pp.orig_write_end_io_work
0.35 ± 11% -0.1 0.27 ± 8% perf-profile.children.cycles-pp.native_queued_spin_lock_slowpath
0.44 ± 4% -0.1 0.36 ± 5% perf-profile.children.cycles-pp.menu_select
0.90 ± 3% -0.1 0.83 ± 5% perf-profile.children.cycles-pp.btrfs_release_path
1.03 ± 3% -0.1 0.96 ± 4% perf-profile.children.cycles-pp.attach_eb_folio_to_filemap
1.70 ± 2% -0.1 1.63 perf-profile.children.cycles-pp.btrfs_update_root
0.12 ± 8% -0.1 0.07 ± 7% perf-profile.children.cycles-pp.tick_nohz_get_sleep_length
0.68 ± 2% -0.1 0.62 ± 3% perf-profile.children.cycles-pp.kmem_cache_alloc_noprof
0.98 ± 2% -0.0 0.94 ± 2% perf-profile.children.cycles-pp.btrfs_bin_search
0.42 ± 5% -0.0 0.38 ± 3% perf-profile.children.cycles-pp.run_delayed_tree_ref
0.42 ± 4% -0.0 0.38 ± 3% perf-profile.children.cycles-pp.alloc_reserved_tree_block
0.22 ± 5% -0.0 0.18 ± 4% perf-profile.children.cycles-pp.add_delayed_ref
0.12 ± 4% -0.0 0.09 ± 12% perf-profile.children.cycles-pp.mempool_alloc_noprof
0.14 ± 5% -0.0 0.11 ± 7% perf-profile.children.cycles-pp.btrfs_get_16
0.08 ± 12% +0.0 0.10 ± 8% perf-profile.children.cycles-pp.sched_tick
0.16 ± 4% +0.0 0.18 ± 5% perf-profile.children.cycles-pp.update_process_times
0.17 ± 15% +0.0 0.20 ± 6% perf-profile.children.cycles-pp.poll_idle
0.12 ± 7% +0.0 0.16 ± 11% perf-profile.children.cycles-pp.update_sg_lb_stats
0.15 ± 7% +0.0 0.18 ± 12% perf-profile.children.cycles-pp.update_sd_lb_stats
0.15 ± 9% +0.0 0.19 ± 10% perf-profile.children.cycles-pp.sched_balance_find_src_group
0.35 ± 4% +0.0 0.40 ± 3% perf-profile.children.cycles-pp.btrfs_search_forward
0.31 ± 5% +0.0 0.36 ± 2% perf-profile.children.cycles-pp.free_extent_buffer
0.00 +0.1 0.05 perf-profile.children.cycles-pp.menu_reflect
0.24 ± 7% +0.1 0.29 ± 7% perf-profile.children.cycles-pp.xas_start
0.35 ± 2% +0.1 0.40 ± 6% perf-profile.children.cycles-pp.__sysvec_apic_timer_interrupt
0.34 ± 3% +0.1 0.39 ± 6% perf-profile.children.cycles-pp.hrtimer_interrupt
0.00 +0.1 0.06 ± 11% perf-profile.children.cycles-pp.rcu_segcblist_enqueue
0.00 +0.1 0.07 ± 36% perf-profile.children.cycles-pp.__slab_free
0.00 +0.1 0.08 ± 19% perf-profile.children.cycles-pp.__kmem_cache_free_bulk
0.00 +0.1 0.09 ± 17% perf-profile.children.cycles-pp.sheaf_flush_unused
0.79 ± 7% +0.1 0.87 ± 2% perf-profile.children.cycles-pp.insert_reserved_file_extent
0.05 ± 47% +0.1 0.15 ± 13% perf-profile.children.cycles-pp.__pcs_replace_full_main
0.00 +0.1 0.12 ± 9% perf-profile.children.cycles-pp.__memcg_slab_free_hook
0.44 ± 6% +0.1 0.56 ± 3% perf-profile.children.cycles-pp.btrfs_drop_extents
0.49 ± 6% +0.2 0.66 ± 3% perf-profile.children.cycles-pp.xa_load
0.26 ± 9% +0.2 0.42 ± 4% perf-profile.children.cycles-pp.btrfs_lookup_file_extent
0.00 +0.2 0.18 ± 9% perf-profile.children.cycles-pp.__call_rcu_common
1.18 ± 4% +0.2 1.37 ± 3% perf-profile.children.cycles-pp.xas_load
0.41 ± 4% +0.2 0.60 ± 5% perf-profile.children.cycles-pp.__btrfs_update_delayed_inode
0.29 ± 5% +0.2 0.49 ± 5% perf-profile.children.cycles-pp.btrfs_lookup_inode
0.57 ± 3% +0.2 0.77 ± 4% perf-profile.children.cycles-pp.btrfs_insert_delayed_item
0.00 +0.2 0.24 ± 7% perf-profile.children.cycles-pp.radix_tree_node_rcu_free
0.02 ± 99% +0.3 0.28 ± 5% perf-profile.children.cycles-pp.rcu_cblist_dequeue
0.00 +0.3 0.33 ± 17% perf-profile.children.cycles-pp.run_ksoftirqd
0.00 +0.3 0.34 ± 17% perf-profile.children.cycles-pp.smpboot_thread_fn
0.00 +0.3 0.34 ± 5% perf-profile.children.cycles-pp.xa_find
1.60 ± 6% +0.4 1.98 ± 2% perf-profile.children.cycles-pp.lookup_open
1.65 ± 6% +0.4 2.06 ± 2% perf-profile.children.cycles-pp.open_last_lookups
1.85 ± 5% +0.4 2.26 ± 2% perf-profile.children.cycles-pp.path_openat
1.85 ± 5% +0.4 2.26 ± 3% perf-profile.children.cycles-pp.do_file_open
1.90 ± 5% +0.4 2.32 ± 3% perf-profile.children.cycles-pp.__x64_sys_openat
1.90 ± 5% +0.4 2.32 ± 3% perf-profile.children.cycles-pp.do_sys_openat2
0.29 ± 10% +0.4 0.72 ± 4% perf-profile.children.cycles-pp.refill_objects
0.36 ± 8% +0.4 0.80 ± 4% perf-profile.children.cycles-pp.__pcs_replace_empty_main
0.13 ± 21% +0.5 0.58 ± 4% perf-profile.children.cycles-pp.__refill_objects_node
0.33 ± 4% +0.5 0.81 ± 2% perf-profile.children.cycles-pp.kmem_cache_free
0.24 ± 8% +0.5 0.76 ± 4% perf-profile.children.cycles-pp.kmem_cache_alloc_lru_noprof
2.15 ± 4% +0.5 2.67 perf-profile.children.cycles-pp.btrfs_finish_one_ordered
3.58 ± 4% +0.5 4.13 ± 2% perf-profile.children.cycles-pp.filename_mkdirat
3.62 ± 5% +0.6 4.17 ± 2% perf-profile.children.cycles-pp.__x64_sys_mkdir
3.66 ± 4% +0.6 4.21 ± 2% perf-profile.children.cycles-pp.mkdir
2.95 ± 5% +0.6 3.51 ± 2% perf-profile.children.cycles-pp.btrfs_mkdir
2.99 ± 5% +0.6 3.55 ± 2% perf-profile.children.cycles-pp.vfs_mkdir
0.00 +0.6 0.59 ± 4% perf-profile.children.cycles-pp.xas_alloc
0.00 +0.7 0.75 ± 4% perf-profile.children.cycles-pp.xas_free_nodes
0.00 +0.8 0.80 ± 4% perf-profile.children.cycles-pp.xa_destroy
0.53 ± 6% +0.8 1.34 ± 8% perf-profile.children.cycles-pp.__irq_exit_rcu
0.06 ± 14% +0.8 0.88 ± 3% perf-profile.children.cycles-pp.xas_create
0.56 ± 3% +0.8 1.39 ± 5% perf-profile.children.cycles-pp.sysvec_apic_timer_interrupt
1.15 ± 3% +0.8 1.98 ± 3% perf-profile.children.cycles-pp.asm_sysvec_apic_timer_interrupt
0.16 ± 6% +0.9 1.02 ± 4% perf-profile.children.cycles-pp.xas_store
32.62 +0.9 33.48 ± 2% perf-profile.children.cycles-pp.kthread
32.62 +0.9 33.48 ± 2% perf-profile.children.cycles-pp.ret_from_fork
32.62 +0.9 33.48 ± 2% perf-profile.children.cycles-pp.ret_from_fork_asm
0.04 ± 71% +0.9 0.94 ± 3% perf-profile.children.cycles-pp.__xa_store
0.05 ± 45% +1.0 1.00 ± 3% perf-profile.children.cycles-pp.xa_store
3.89 ± 5% +1.0 4.88 ± 2% perf-profile.children.cycles-pp.btrfs_create_common
0.00 +1.0 1.01 ± 3% perf-profile.children.cycles-pp.xa_find_after
0.10 ± 11% +1.1 1.18 perf-profile.children.cycles-pp.rcu_do_batch
0.12 ± 10% +1.1 1.20 ± 2% perf-profile.children.cycles-pp.rcu_core
1.11 ± 2% +1.1 2.21 ± 3% perf-profile.children.cycles-pp.btrfs_async_run_delayed_root
0.47 ± 7% +1.1 1.62 ± 4% perf-profile.children.cycles-pp.handle_softirqs
0.00 +1.2 1.24 ± 4% perf-profile.children.cycles-pp.btrfs_inhibit_eb_writeback
0.00 +1.3 1.31 ± 3% perf-profile.children.cycles-pp.xas_find
3.27 ± 3% +1.6 4.89 perf-profile.children.cycles-pp.btrfs_work_helper
0.00 +2.3 2.28 ± 3% perf-profile.children.cycles-pp.btrfs_uninhibit_all_eb_writeback
0.12 ± 6% +2.3 2.40 ± 2% perf-profile.children.cycles-pp.__btrfs_end_transaction
1.93 ± 10% -0.6 1.32 ± 11% perf-profile.self.cycles-pp.mutex_spin_on_owner
3.90 ± 15% -0.6 3.32 ± 2% perf-profile.self.cycles-pp.brd_rw_bvec
3.18 ± 10% -0.4 2.82 perf-profile.self.cycles-pp.__pi_memcpy
0.34 ± 11% -0.1 0.26 ± 8% perf-profile.self.cycles-pp.native_queued_spin_lock_slowpath
0.97 ± 2% -0.0 0.92 ± 2% perf-profile.self.cycles-pp.btrfs_bin_search
0.12 ± 5% -0.0 0.10 ± 8% perf-profile.self.cycles-pp.btrfs_get_16
0.12 ± 5% -0.0 0.10 ± 8% perf-profile.self.cycles-pp.set_extent_buffer_dirty
0.08 ± 13% +0.0 0.10 ± 11% perf-profile.self.cycles-pp.rwsem_down_write_slowpath
0.10 ± 7% +0.0 0.14 ± 12% perf-profile.self.cycles-pp.update_sg_lb_stats
0.06 ± 13% +0.0 0.10 ± 14% perf-profile.self.cycles-pp.xas_store
0.00 +0.1 0.06 ± 11% perf-profile.self.cycles-pp.rcu_segcblist_enqueue
0.00 +0.1 0.06 ± 13% perf-profile.self.cycles-pp.btrfs_uninhibit_all_eb_writeback
0.08 ± 8% +0.1 0.16 ± 3% perf-profile.self.cycles-pp.free_extent_buffer
0.00 +0.1 0.07 ± 11% perf-profile.self.cycles-pp.kmem_cache_alloc_lru_noprof
0.00 +0.1 0.10 ± 10% perf-profile.self.cycles-pp.rcu_do_batch
0.00 +0.1 0.10 ± 10% perf-profile.self.cycles-pp.__memcg_slab_free_hook
0.00 +0.1 0.13 ± 9% perf-profile.self.cycles-pp.__call_rcu_common
0.94 ± 4% +0.1 1.07 ± 3% perf-profile.self.cycles-pp.xas_load
0.00 +0.1 0.13 ± 7% perf-profile.self.cycles-pp.btrfs_inhibit_eb_writeback
0.00 +0.2 0.22 ± 7% perf-profile.self.cycles-pp.radix_tree_node_rcu_free
0.00 +0.3 0.25 ± 5% perf-profile.self.cycles-pp.xas_create
0.02 ±141% +0.3 0.27 ± 5% perf-profile.self.cycles-pp.rcu_cblist_dequeue
0.25 ± 5% +0.3 0.53 ± 4% perf-profile.self.cycles-pp.kmem_cache_free
0.12 ± 19% +0.4 0.55 ± 4% perf-profile.self.cycles-pp.__refill_objects_node
0.00 +0.6 0.60 ± 4% perf-profile.self.cycles-pp.xas_free_nodes
0.00 +1.2 1.24 ± 2% perf-profile.self.cycles-pp.xas_find

***************************************************************************************************

=========================================================================================
bs/compiler/cpufreq_governor/disk/fs/ioengine/kconfig/nr_task/rootfs/runtime/rw/tbox_group/test_size/testcase:
4k/gcc-14/performance/1HDD/btrfs/sync/x86_64-rhel-9.4/1/debian-13-x86_64-20250902.cgz/300s/randwrite/lkp-icl-2sp9/128G/fio-basic

commit:
ed7bc52711 ("btrfs: extract the max compression chunk size into a macro")
f9d138838a ("btrfs: inhibit extent buffer writeback to prevent COW amplification")

ed7bc52711022142 f9d138838a78bf2a5263ad3c1d3
---------------- ---------------------------
%stddev %change %stddev
\ | \
0.89 ± 2% +1.0 1.89 ± 7% fio.latency_1000us%
0.03 ± 6% +0.0 0.05 ± 11% fio.latency_100ms%
0.01 +0.0 0.02 ± 12% fio.latency_250ms%
0.32 ± 3% +0.1 0.42 ± 6% fio.latency_2ms%
0.05 ± 7% +0.0 0.06 ± 5% fio.latency_4ms%
0.05 +0.0 0.05 ± 3% fio.latency_500ms%
3865002 -7.4% 3579840 fio.time.file_system_outputs
570083 -5.0% 541708 fio.time.voluntary_context_switches
483125 -7.4% 447480 fio.workload
6.29 -7.4% 5.82 fio.write_bw_MBps
451925 +2.9% 464896 fio.write_clat_95%_ns
1471829 +28.2% 1886890 ± 15% fio.write_clat_99%_ns
620355 +8.0% 670119 fio.write_clat_mean_ns
9919039 +3.0% 10218735 fio.write_clat_stddev
1609 -7.4% 1490 fio.write_iops
1.66 +8.0% 1.79 iostat.cpu.iowait
145.17 ± 13% -27.2% 105.67 ± 17% perf-c2c.DRAM.local
0.99 +6.9% 1.06 turbostat.IPC
1.67 +0.1 1.80 mpstat.cpu.all.iowait%
0.00 ± 6% +0.0 0.01 ± 7% mpstat.cpu.all.soft%
0.15 ± 3% +0.0 0.16 ± 3% mpstat.cpu.all.sys%
11959 +46.9% 17567 ± 4% vmstat.io.bo
4278391 +5.0% 4490659 vmstat.memory.cache
1.06 +8.0% 1.15 vmstat.procs.b
11633 -3.2% 11258 vmstat.system.cs
1.556e+08 ± 5% +10.6% 1.721e+08 ± 4% perf-stat.i.branch-instructions
502335 ± 7% +15.0% 577499 ± 7% perf-stat.i.cache-misses
3737605 ± 2% +7.3% 4009808 ± 2% perf-stat.i.cache-references
11695 -3.3% 11304 perf-stat.i.context-switches
1.03 -9.5% 0.93 perf-stat.i.cpi
8.222e+08 ± 5% +11.0% 9.127e+08 ± 4% perf-stat.i.instructions
1.06 +12.9% 1.20 perf-stat.i.ipc
1.06 -6.5% 0.99 perf-stat.overall.cpi
1746 ± 3% -9.7% 1577 ± 3% perf-stat.overall.cycles-between-cache-misses
0.94 +7.0% 1.01 perf-stat.overall.ipc
512147 ± 5% +19.9% 614104 ± 5% perf-stat.overall.path-length
1.552e+08 ± 5% +10.6% 1.717e+08 ± 4% perf-stat.ps.branch-instructions
500755 ± 7% +15.0% 575704 ± 7% perf-stat.ps.cache-misses
3728960 ± 2% +7.3% 4000930 ± 2% perf-stat.ps.cache-references
11657 -3.3% 11267 perf-stat.ps.context-switches
8.201e+08 ± 5% +11.0% 9.105e+08 ± 4% perf-stat.ps.instructions
2.474e+11 ± 5% +11.0% 2.747e+11 ± 4% perf-stat.total.instructions
20.76 ± 4% -1.8 19.01 ± 5% perf-profile.calltrace.cycles-pp.asm_sysvec_call_function_single.pv_native_safe_halt.acpi_safe_halt.acpi_idle_do_entry.acpi_idle_enter
1.03 ± 7% -0.2 0.80 ± 14% perf-profile.calltrace.cycles-pp.btrfs_lookup_csums_list.can_nocow_file_extent.run_delalloc_nocow.writepage_delalloc.extent_writepage
1.02 ± 10% -0.2 0.82 ± 22% perf-profile.calltrace.cycles-pp.push_leaf_right.split_leaf.btrfs_search_slot.btrfs_insert_empty_items.btrfs_insert_data_csums
0.95 ± 9% -0.2 0.78 ± 16% perf-profile.calltrace.cycles-pp.btrfs_get_32.setup_items_for_insert.btrfs_insert_empty_items.btrfs_insert_data_csums.btrfs_finish_one_ordered
1.24 ± 4% +0.3 1.50 ± 7% perf-profile.calltrace.cycles-pp.__irq_exit_rcu.sysvec_apic_timer_interrupt.asm_sysvec_apic_timer_interrupt.pv_native_safe_halt.acpi_safe_halt
1.17 ± 4% +0.3 1.46 ± 7% perf-profile.calltrace.cycles-pp.handle_softirqs.__irq_exit_rcu.sysvec_apic_timer_interrupt.asm_sysvec_apic_timer_interrupt.pv_native_safe_halt
0.63 ± 9% +0.3 0.96 ± 6% perf-profile.calltrace.cycles-pp.rcu_core.handle_softirqs.__irq_exit_rcu.sysvec_apic_timer_interrupt.asm_sysvec_apic_timer_interrupt
0.00 +0.6 0.57 ± 10% perf-profile.calltrace.cycles-pp.kmem_cache_free.rcu_do_batch.rcu_core.handle_softirqs.__irq_exit_rcu
0.18 ±141% +0.6 0.81 ± 4% perf-profile.calltrace.cycles-pp.rcu_do_batch.rcu_core.handle_softirqs.__irq_exit_rcu.sysvec_apic_timer_interrupt
0.00 +0.7 0.70 ± 24% perf-profile.calltrace.cycles-pp.xas_free_nodes.xa_destroy.btrfs_uninhibit_all_eb_writeback.__btrfs_end_transaction.btrfs_finish_one_ordered
0.00 +0.7 0.73 ± 23% perf-profile.calltrace.cycles-pp.xa_destroy.btrfs_uninhibit_all_eb_writeback.__btrfs_end_transaction.btrfs_finish_one_ordered.btrfs_work_helper
10.75 ± 3% +0.7 11.50 ± 3% perf-profile.calltrace.cycles-pp.asm_sysvec_apic_timer_interrupt.pv_native_safe_halt.acpi_safe_halt.acpi_idle_do_entry.acpi_idle_enter
0.00 +0.9 0.86 ± 18% perf-profile.calltrace.cycles-pp.xas_find.xa_find_after.btrfs_uninhibit_all_eb_writeback.__btrfs_end_transaction.btrfs_finish_one_ordered
0.00 +0.9 0.89 ± 20% perf-profile.calltrace.cycles-pp.xa_find_after.btrfs_uninhibit_all_eb_writeback.__btrfs_end_transaction.btrfs_finish_one_ordered.btrfs_work_helper
0.00 +2.0 1.96 ± 17% perf-profile.calltrace.cycles-pp.btrfs_uninhibit_all_eb_writeback.__btrfs_end_transaction.btrfs_finish_one_ordered.btrfs_work_helper.process_one_work
0.00 +2.0 2.00 ± 17% perf-profile.calltrace.cycles-pp.__btrfs_end_transaction.btrfs_finish_one_ordered.btrfs_work_helper.process_one_work.worker_thread
12.30 ± 5% -0.9 11.42 ± 5% perf-profile.children.cycles-pp.asm_sysvec_call_function_single
1.03 ± 7% -0.2 0.80 ± 14% perf-profile.children.cycles-pp.btrfs_lookup_csums_list
0.32 ± 30% -0.1 0.18 ± 26% perf-profile.children.cycles-pp.lapic_next_deadline
0.42 ± 13% -0.1 0.28 ± 35% perf-profile.children.cycles-pp.release_extent_buffer
0.29 ± 5% -0.1 0.20 ± 39% perf-profile.children.cycles-pp.alloc_ordered_extent
0.22 ± 17% -0.1 0.13 ± 31% perf-profile.children.cycles-pp.lru_add
0.22 ± 26% -0.1 0.15 ± 29% perf-profile.children.cycles-pp.update_cfs_rq_load_avg
0.15 ± 38% -0.1 0.07 ± 54% perf-profile.children.cycles-pp.__update_load_avg_cfs_rq
0.18 ± 26% +0.1 0.27 ± 21% perf-profile.children.cycles-pp.refill_objects
0.10 ± 43% +0.1 0.22 ± 22% perf-profile.children.cycles-pp.__refill_objects_node
0.16 ± 21% +0.1 0.28 ± 17% perf-profile.children.cycles-pp.__memcg_slab_free_hook
0.10 ± 41% +0.1 0.22 ± 30% perf-profile.children.cycles-pp.xa_find
0.81 ± 12% +0.2 0.97 ± 4% perf-profile.children.cycles-pp.kmem_cache_free
0.39 ± 19% +0.2 0.57 ± 19% perf-profile.children.cycles-pp.xas_alloc
0.34 ± 24% +0.2 0.54 ± 19% perf-profile.children.cycles-pp.kmem_cache_alloc_lru_noprof
2.11 ± 5% +0.3 2.41 ± 7% perf-profile.children.cycles-pp.handle_softirqs
0.72 ± 10% +0.3 1.06 ± 10% perf-profile.children.cycles-pp.rcu_core
0.54 ± 13% +0.4 0.90 ± 9% perf-profile.children.cycles-pp.rcu_do_batch
0.47 ± 21% +0.4 0.88 ± 20% perf-profile.children.cycles-pp.xas_create
0.00 +0.5 0.45 ± 32% perf-profile.children.cycles-pp.__xa_store
0.01 ±223% +0.5 0.52 ± 21% perf-profile.children.cycles-pp.xa_store
0.00 +0.7 0.72 ± 23% perf-profile.children.cycles-pp.xas_free_nodes
0.00 +0.7 0.74 ± 23% perf-profile.children.cycles-pp.xa_destroy
0.00 +0.7 0.74 ± 11% perf-profile.children.cycles-pp.btrfs_inhibit_eb_writeback
0.00 +0.9 0.90 ± 21% perf-profile.children.cycles-pp.xa_find_after
0.06 ± 23% +2.0 2.01 ± 17% perf-profile.children.cycles-pp.__btrfs_end_transaction
0.00 +2.0 1.97 ± 17% perf-profile.children.cycles-pp.btrfs_uninhibit_all_eb_writeback
0.87 ± 11% -0.2 0.63 ± 11% perf-profile.self.cycles-pp.find_extent_buffer
0.32 ± 30% -0.1 0.18 ± 26% perf-profile.self.cycles-pp.lapic_next_deadline
0.29 ± 12% -0.1 0.17 ± 35% perf-profile.self.cycles-pp.release_extent_buffer
0.17 ± 34% -0.1 0.06 ±113% perf-profile.self.cycles-pp.refresh_cpu_vm_stats
0.13 ± 30% -0.1 0.04 ±109% perf-profile.self.cycles-pp.___perf_sw_event
0.14 ± 39% -0.1 0.07 ± 54% perf-profile.self.cycles-pp.__update_load_avg_cfs_rq
0.10 ± 43% +0.1 0.21 ± 22% perf-profile.self.cycles-pp.__refill_objects_node
0.04 ± 72% +0.2 0.22 ± 19% perf-profile.self.cycles-pp.__memcg_slab_free_hook
0.07 ± 62% +0.2 0.25 ± 46% perf-profile.self.cycles-pp.xas_create
0.00 +0.6 0.55 ± 21% perf-profile.self.cycles-pp.xas_free_nodes
0.02 ±144% +1.0 1.00 ± 21% perf-profile.self.cycles-pp.xas_find

***************************************************************************************************

=========================================================================================
bs/compiler/cpufreq_governor/disk/fs/ioengine/kconfig/nr_task/rootfs/runtime/rw/tbox_group/test_size/testcase:
4k/gcc-14/performance/1HDD/btrfs/vsync/x86_64-rhel-9.4/1/debian-13-x86_64-20250902.cgz/300s/randwrite/lkp-icl-2sp9/128G/fio-basic

commit:
ed7bc52711 ("btrfs: extract the max compression chunk size into a macro")
f9d138838a ("btrfs: inhibit extent buffer writeback to prevent COW amplification")

ed7bc52711022142 f9d138838a78bf2a5263ad3c1d3
---------------- ---------------------------
%stddev %change %stddev
\ | \
0.89 +0.9 1.83 ± 12% fio.latency_1000us%
0.03 ± 4% +0.0 0.05 ± 14% fio.latency_100ms%
0.11 ± 6% +0.0 0.13 ± 8% fio.latency_10ms%
0.01 +0.0 0.02 ± 13% fio.latency_250ms%
0.31 ± 4% +0.1 0.41 ± 5% fio.latency_2ms%
37.86 ± 2% -1.7 36.12 ± 2% fio.latency_500us%
3854986 -6.8% 3593881 fio.time.file_system_outputs
567967 -4.4% 543118 fio.time.voluntary_context_switches
481873 -6.8% 449235 fio.workload
6.27 -6.8% 5.85 fio.write_bw_MBps
453290 +2.6% 464896 fio.write_clat_95%_ns
1466368 ± 2% +22.6% 1798144 ± 12% fio.write_clat_99%_ns
622174 +7.3% 667670 fio.write_clat_mean_ns
9947977 +3.0% 10249056 fio.write_clat_stddev
1605 -6.8% 1496 fio.write_iops
1.65 +7.1% 1.77 iostat.cpu.iowait
144.00 ± 16% -35.1% 93.50 ± 37% perf-c2c.DRAM.local
0.36 ± 6% +0.0 0.39 ± 5% turbostat.Busy%
1.66 +0.1 1.78 ± 2% mpstat.cpu.all.iowait%
0.01 ± 10% +0.0 0.01 ± 3% mpstat.cpu.all.soft%
0.15 ± 3% +0.0 0.16 ± 3% mpstat.cpu.all.sys%
11889 +45.8% 17333 ± 6% vmstat.io.bo
1.07 +6.5% 1.14 ± 2% vmstat.procs.b
11603 -2.9% 11267 vmstat.system.cs
1.559e+08 ± 5% +14.4% 1.784e+08 ± 5% perf-stat.i.branch-instructions
503477 ± 9% +22.1% 614867 ± 8% perf-stat.i.cache-misses
3748321 ± 2% +9.6% 4107956 ± 2% perf-stat.i.cache-references
11658 -2.9% 11315 perf-stat.i.context-switches
1.03 -8.8% 0.94 perf-stat.i.cpi
8.761e+08 ± 6% +8.0% 9.462e+08 ± 5% perf-stat.i.cpu-cycles
8.236e+08 ± 5% +14.5% 9.433e+08 ± 5% perf-stat.i.instructions
1.06 +11.7% 1.18 perf-stat.i.ipc
1.06 -5.7% 1.00 perf-stat.overall.cpi
1748 ± 3% -11.6% 1545 ± 3% perf-stat.overall.cycles-between-cache-misses
0.94 +6.0% 1.00 perf-stat.overall.ipc
514394 ± 5% +23.1% 632989 ± 7% perf-stat.overall.path-length
1.555e+08 ± 5% +14.4% 1.779e+08 ± 5% perf-stat.ps.branch-instructions
501891 ± 9% +22.1% 612976 ± 8% perf-stat.ps.cache-misses
3739078 ± 2% +9.6% 4097784 ± 2% perf-stat.ps.cache-references
11620 -2.9% 11278 perf-stat.ps.context-switches
8.748e+08 ± 6% +8.0% 9.448e+08 ± 5% perf-stat.ps.cpu-cycles
8.215e+08 ± 5% +14.5% 9.409e+08 ± 5% perf-stat.ps.instructions
2.478e+11 ± 5% +14.6% 2.84e+11 ± 5% perf-stat.total.instructions
1.38 ± 48% -0.5 0.84 ± 16% perf-profile.calltrace.cycles-pp.prepare_one_folio.copy_one_range.btrfs_buffered_write.btrfs_direct_write.btrfs_do_write_iter
0.66 ± 14% +0.4 1.05 ± 16% perf-profile.calltrace.cycles-pp.rcu_core.handle_softirqs.__irq_exit_rcu.sysvec_apic_timer_interrupt.asm_sysvec_apic_timer_interrupt
0.31 ±100% +0.6 0.89 ± 19% perf-profile.calltrace.cycles-pp.rcu_do_batch.rcu_core.handle_softirqs.__irq_exit_rcu.sysvec_apic_timer_interrupt
3.33 ± 11% +0.7 4.06 ± 10% perf-profile.calltrace.cycles-pp.sysvec_apic_timer_interrupt.asm_sysvec_apic_timer_interrupt.pv_native_safe_halt.acpi_safe_halt.acpi_idle_do_entry
0.00 +0.8 0.77 ± 18% perf-profile.calltrace.cycles-pp.xas_free_nodes.xa_destroy.btrfs_uninhibit_all_eb_writeback.__btrfs_end_transaction.btrfs_finish_one_ordered
0.00 +0.8 0.78 ± 17% perf-profile.calltrace.cycles-pp.xa_destroy.btrfs_uninhibit_all_eb_writeback.__btrfs_end_transaction.btrfs_finish_one_ordered.btrfs_work_helper
0.00 +0.8 0.85 ± 26% perf-profile.calltrace.cycles-pp.xas_find.xa_find_after.btrfs_uninhibit_all_eb_writeback.__btrfs_end_transaction.btrfs_finish_one_ordered
0.00 +0.9 0.89 ± 27% perf-profile.calltrace.cycles-pp.xa_find_after.btrfs_uninhibit_all_eb_writeback.__btrfs_end_transaction.btrfs_finish_one_ordered.btrfs_work_helper
0.00 +2.1 2.09 ± 20% perf-profile.calltrace.cycles-pp.btrfs_uninhibit_all_eb_writeback.__btrfs_end_transaction.btrfs_finish_one_ordered.btrfs_work_helper.process_one_work
0.00 +2.1 2.14 ± 19% perf-profile.calltrace.cycles-pp.__btrfs_end_transaction.btrfs_finish_one_ordered.btrfs_work_helper.process_one_work.worker_thread
1.38 ± 48% -0.5 0.84 ± 16% perf-profile.children.cycles-pp.prepare_one_folio
1.03 ± 16% -0.3 0.72 ± 34% perf-profile.children.cycles-pp.copy_extent_buffer_full
0.28 ± 15% -0.1 0.15 ± 31% perf-profile.children.cycles-pp.set_next_task_fair
0.16 ± 53% -0.1 0.06 ± 62% perf-profile.children.cycles-pp.refresh_cpu_vm_stats
0.13 ± 14% -0.0 0.08 ± 25% perf-profile.children.cycles-pp.igrab
0.05 ±114% +0.1 0.18 ± 41% perf-profile.children.cycles-pp.__refill_objects_node
0.16 ± 36% +0.2 0.31 ± 36% perf-profile.children.cycles-pp.__memcg_slab_free_hook
0.01 ±223% +0.3 0.29 ± 40% perf-profile.children.cycles-pp.xa_find
0.22 ± 24% +0.3 0.52 ± 77% perf-profile.children.cycles-pp.__pcs_replace_empty_main
0.61 ± 17% +0.4 1.03 ± 15% perf-profile.children.cycles-pp.rcu_do_batch
0.75 ± 13% +0.5 1.21 ± 13% perf-profile.children.cycles-pp.rcu_core
0.02 ±149% +0.5 0.50 ± 24% perf-profile.children.cycles-pp.__xa_store
0.04 ±101% +0.5 0.56 ± 23% perf-profile.children.cycles-pp.xa_store
3.52 ± 11% +0.7 4.24 ± 9% perf-profile.children.cycles-pp.sysvec_apic_timer_interrupt
0.00 +0.8 0.78 ± 18% perf-profile.children.cycles-pp.xas_free_nodes
0.00 +0.8 0.80 ± 18% perf-profile.children.cycles-pp.xa_destroy
0.00 +0.8 0.84 ± 21% perf-profile.children.cycles-pp.btrfs_inhibit_eb_writeback
0.00 +0.9 0.90 ± 28% perf-profile.children.cycles-pp.xa_find_after
0.69 ± 46% +0.9 1.62 ± 20% perf-profile.children.cycles-pp.xas_find
0.00 +2.1 2.10 ± 20% perf-profile.children.cycles-pp.btrfs_uninhibit_all_eb_writeback
0.02 ±144% +2.1 2.16 ± 19% perf-profile.children.cycles-pp.__btrfs_end_transaction
2.78 ± 4% -0.3 2.51 ± 8% perf-profile.self.cycles-pp._raw_spin_lock
0.27 ± 21% -0.1 0.19 ± 23% perf-profile.self.cycles-pp.irqentry_enter
0.18 ± 25% -0.1 0.10 ± 36% perf-profile.self.cycles-pp._raw_read_lock
0.08 ± 12% +0.1 0.16 ± 41% perf-profile.self.cycles-pp.xas_store
0.10 ± 22% +0.1 0.22 ± 20% perf-profile.self.cycles-pp.xas_create
0.00 +0.1 0.12 ± 30% perf-profile.self.cycles-pp.btrfs_inhibit_eb_writeback
0.36 ± 16% +0.1 0.51 ± 22% perf-profile.self.cycles-pp.kmem_cache_free
0.10 ± 40% +0.1 0.24 ± 35% perf-profile.self.cycles-pp.__memcg_slab_free_hook
0.02 ±144% +0.2 0.17 ± 32% perf-profile.self.cycles-pp.__call_rcu_common
0.00 +0.6 0.61 ± 22% perf-profile.self.cycles-pp.xas_free_nodes
0.01 ±223% +1.1 1.08 ± 25% perf-profile.self.cycles-pp.xas_find

***************************************************************************************************

=========================================================================================
bs/compiler/cpufreq_governor/disk/fs/ioengine/kconfig/nr_task/rootfs/runtime/rw/tbox_group/test_size/testcase:
4k/gcc-14/performance/1HDD/btrfs/ftruncate/x86_64-rhel-9.4/1/debian-13-x86_64-20250902.cgz/300s/randwrite/lkp-icl-2sp9/128G/fio-basic

commit:
ed7bc52711 ("btrfs: extract the max compression chunk size into a macro")
f9d138838a ("btrfs: inhibit extent buffer writeback to prevent COW amplification")

ed7bc52711022142 f9d138838a78bf2a5263ad3c1d3
---------------- ---------------------------
%stddev %change %stddev
\ | \
0.05 ± 38% +0.4 0.41 ± 9% fio.latency_10us%
0.01 ± 70% +0.0 0.03 ± 9% fio.latency_250us%
99.84 -47.3 52.50 ± 6% fio.latency_2us%
0.11 ± 18% +46.9 47.04 ± 7% fio.latency_4us%
58.71 +27.9% 75.08 fio.time.elapsed_time
58.71 +27.9% 75.08 fio.time.elapsed_time.max
444.67 ± 3% +2993.8% 13757 ± 9% fio.time.involuntary_context_switches
101.00 -3.0% 98.00 fio.time.percent_of_cpu_this_job_got
46.25 +29.8% 60.03 fio.time.system_time
6247 +27.8% 7981 fio.time.voluntary_context_switches
2248 -21.9% 1754 fio.write_bw_MBps
1560 +38.1% 2154 fio.write_clat_90%_ns
1570 +42.6% 2240 fio.write_clat_95%_ns
1616 +93.7% 3130 fio.write_clat_99%_ns
1477 +32.4% 1956 fio.write_clat_mean_ns
357.00 ± 26% +802.8% 3223 ± 3% fio.write_clat_stddev
575507 -21.9% 449271 fio.write_iops
1876 +15.3% 2162 vmstat.system.cs
3.782e+09 +27.4% 4.816e+09 cpuidle..time
134072 ± 3% +51.1% 202619 ± 3% cpuidle..usage
0.00 ± 10% +0.0 0.02 ± 9% mpstat.cpu.all.soft%
0.95 ± 5% -0.2 0.74 ± 9% mpstat.cpu.all.usr%
32.78 ± 44% +4925.0% 1647 ± 67% perf-sched.total_wait_time.max.ms
32.78 ± 44% +4925.0% 1647 ± 67% perf-sched.wait_time.max.ms.[unknown].[unknown].[unknown].[unknown].[unknown]
1.52 +7.3% 1.63 turbostat.IPC
231880 ± 2% +36.3% 316138 turbostat.IRQ
107.88 +16.4% 125.57 ± 2% uptime.boot
6556 +17.0% 7669 ± 2% uptime.idle
1.29 ± 7% -0.3 1.01 ± 10% perf-stat.i.branch-miss-rate%
8.37 ± 16% -6.0 2.37 ± 7% perf-stat.i.cache-miss-rate%
6027778 ± 6% +205.8% 18432463 ± 2% perf-stat.i.cache-references
1680 +19.0% 1999 ± 2% perf-stat.i.context-switches
0.64 -7.0% 0.60 perf-stat.i.cpi
6.085e+09 ± 3% -9.4% 5.513e+09 ± 4% perf-stat.i.cpu-cycles
71.62 +10.6% 79.18 ± 3% perf-stat.i.cpu-migrations
61976 ± 54% -57.1% 26570 ± 4% perf-stat.i.cycles-between-cache-misses
1.70 +6.4% 1.81 perf-stat.i.ipc
9.32 ± 7% -6.5 2.82 ± 9% perf-stat.overall.cache-miss-rate%
0.66 -6.8% 0.62 perf-stat.overall.cpi
1.51 +7.3% 1.62 perf-stat.overall.ipc
16259 +23.8% 20127 ± 2% perf-stat.overall.path-length
5940856 ± 6% +206.4% 18200387 ± 2% perf-stat.ps.cache-references
1652 +19.4% 1973 ± 2% perf-stat.ps.context-switches
5.99e+09 ± 3% -9.1% 5.446e+09 ± 4% perf-stat.ps.cpu-cycles
70.46 +10.9% 78.15 ± 3% perf-stat.ps.cpu-migrations
5.456e+11 +23.8% 6.754e+11 ± 2% perf-stat.total.instructions
12.96 ± 59% -9.6 3.35 ±119% perf-profile.calltrace.cycles-pp.getdents64
11.76 ± 46% -8.4 3.35 ±119% perf-profile.calltrace.cycles-pp.__x64_sys_getdents64.do_syscall_64.entry_SYSCALL_64_after_hwframe.getdents64
11.76 ± 46% -8.4 3.35 ±119% perf-profile.calltrace.cycles-pp.do_syscall_64.entry_SYSCALL_64_after_hwframe.getdents64
11.76 ± 46% -8.4 3.35 ±119% perf-profile.calltrace.cycles-pp.entry_SYSCALL_64_after_hwframe.getdents64
11.76 ± 46% -8.4 3.35 ±119% perf-profile.calltrace.cycles-pp.iterate_dir.__x64_sys_getdents64.do_syscall_64.entry_SYSCALL_64_after_hwframe.getdents64
11.76 ± 46% -8.4 3.35 ±119% perf-profile.calltrace.cycles-pp.proc_pid_readdir.iterate_dir.__x64_sys_getdents64.do_syscall_64.entry_SYSCALL_64_after_hwframe
6.91 ± 54% -5.2 1.67 ±223% perf-profile.calltrace.cycles-pp.proc_reg_read_iter.vfs_read.ksys_read.do_syscall_64.entry_SYSCALL_64_after_hwframe
6.91 ± 54% -5.2 1.67 ±223% perf-profile.calltrace.cycles-pp.seq_read_iter.proc_reg_read_iter.vfs_read.ksys_read.do_syscall_64
5.51 ± 73% -4.7 0.83 ±223% perf-profile.calltrace.cycles-pp.handle_internal_command.main
5.51 ± 73% -4.7 0.83 ±223% perf-profile.calltrace.cycles-pp.main
5.51 ± 73% -4.7 0.83 ±223% perf-profile.calltrace.cycles-pp.run_builtin.handle_internal_command.main
4.63 ± 72% -4.6 0.00 perf-profile.calltrace.cycles-pp.__evlist__enable.cmd_record.cmd_sched.run_builtin.handle_internal_command
4.63 ± 72% -4.6 0.00 perf-profile.calltrace.cycles-pp.cmd_record.cmd_sched.run_builtin.handle_internal_command.main
4.63 ± 72% -4.6 0.00 perf-profile.calltrace.cycles-pp.cmd_sched.run_builtin.handle_internal_command.main
6.18 ± 85% -4.4 1.76 ±141% perf-profile.calltrace.cycles-pp.next_tgid.proc_pid_readdir.iterate_dir.__x64_sys_getdents64.do_syscall_64
4.70 ±112% -4.0 0.67 ±223% perf-profile.calltrace.cycles-pp.proc_fill_cache.proc_pid_readdir.iterate_dir.__x64_sys_getdents64.do_syscall_64
4.59 ± 73% -3.8 0.83 ±223% perf-profile.calltrace.cycles-pp.arch_show_interrupts.seq_read_iter.proc_reg_read_iter.vfs_read.ksys_read
4.74 ± 73% -2.8 1.97 ±141% perf-profile.calltrace.cycles-pp.folios_put_refs.free_pages_and_swap_cache.__tlb_batch_free_encoded_pages.tlb_flush_mmu.zap_pte_range
3.31 ±103% -1.8 1.50 ±142% perf-profile.calltrace.cycles-pp.vm_mmap_pgoff.ksys_mmap_pgoff.do_syscall_64.entry_SYSCALL_64_after_hwframe
12.96 ± 59% -9.6 3.35 ±119% perf-profile.children.cycles-pp.getdents64
11.76 ± 46% -8.4 3.35 ±119% perf-profile.children.cycles-pp.__x64_sys_getdents64
11.76 ± 46% -8.4 3.35 ±119% perf-profile.children.cycles-pp.iterate_dir
11.76 ± 46% -8.4 3.35 ±119% perf-profile.children.cycles-pp.proc_pid_readdir
5.51 ± 73% -5.5 0.00 perf-profile.children.cycles-pp.__evlist__enable
6.91 ± 54% -5.2 1.67 ±223% perf-profile.children.cycles-pp.proc_reg_read_iter
5.51 ± 73% -4.7 0.83 ±223% perf-profile.children.cycles-pp.cmd_record
5.51 ± 73% -4.7 0.83 ±223% perf-profile.children.cycles-pp.handle_internal_command
5.51 ± 73% -4.7 0.83 ±223% perf-profile.children.cycles-pp.main
5.51 ± 73% -4.7 0.83 ±223% perf-profile.children.cycles-pp.run_builtin
4.63 ± 72% -4.6 0.00 perf-profile.children.cycles-pp.cmd_sched
6.18 ± 85% -4.4 1.76 ±141% perf-profile.children.cycles-pp.next_tgid
5.06 ±115% -4.1 0.93 ±223% perf-profile.children.cycles-pp.d_alloc_parallel
4.70 ±112% -4.0 0.67 ±223% perf-profile.children.cycles-pp.proc_fill_cache
4.80 ±116% -4.0 0.76 ±223% perf-profile.children.cycles-pp.asm_sysvec_apic_timer_interrupt
4.59 ± 73% -3.8 0.83 ±223% perf-profile.children.cycles-pp.arch_show_interrupts
3.62 ±101% -2.0 1.67 ±223% perf-profile.children.cycles-pp.its_return_thunk
31.46 ± 27% +14.7 46.18 ± 19% perf-profile.children.cycles-pp.do_exit
31.46 ± 27% +14.7 46.18 ± 19% perf-profile.children.cycles-pp.do_group_exit

Disclaimer:
Results have been estimated based on internal Intel analysis and are provided
for informational purposes only. Any difference in system hardware or software
design or configuration may affect actual performance.

--
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