10.31 second kernel compile

Anton Blanchard
2002-03-13T10:12:47Z

Let the kernel compile benchmarks continue!

hardware: 24 way logical partition, 1.1GHz POWER4, 60G RAM

kernel: 2.5.6 + ppc64 pagetable rework

kernel compiled: 2.4.18 x86 with Martin's config

compiler: gcc 2.95.3 x86 cross compiler

# MAKE="make -j14" /usr/bin/time make -j14 bzImage
...
make[1]: Leaving directory `/home/anton/intel_kernel/linux/arch/i386/boot'
130.63user 71.31system 0:10.31elapsed 1957%CPU (0avgtext+0avgdata 0maxresident)k

Due to the final link and compress stage, there is a fair amount of idle
time at the end of the run. Its going to be hard to push that number
lower by adding cpus.

The profile results below show that kernel time is dominated by the low
level ppc64 pagetable management. We are working to correct this, a lot
of the overhead in __hash_page should be gone soon. The rest of the
profile looks pretty good, do_anonymous_page and lru_cache_add show
up high as they did in Martin's results.

Thanks to Milton Miller who helped with the benchmarking, and the ppc64
team!

Anton
--
anton@samba.org
anton@au.ibm.com

201150 total 0.0668
129051 .idled

43586 .__hash_page ppc64 specific
6714 .local_flush_tlb_range ppc64 specific
2773 .local_flush_tlb_page ppc64 specific

2203 .do_anonymous_page
2059 .lru_cache_add
1379 .__copy_tofrom_user

1220 .hpte_create_valid_pSeriesLP ppc64 LPAR specific

1039 .save_remaining_regs
871 .do_page_fault

575 .plpar_hcall ppc64 LPAR specific

554 .d_lookup
545 .rmqueue
482 .copy_page
475 .__strnlen_user
391 .__free_pages_ok
389 .zap_page_range
366 .atomic_dec_and_lock
296 .__find_get_page
287 .set_page_dirty
278 .page_cache_release
218 .handle_mm_fault
199 .__flush_dcache_icache
175 .schedule
173 .sys_brk
163 .exit_notify
156 .do_no_page
152 .lru_cache_del
147 .__wake_up
146 .copy_page_range
139 .ppc_irq_dispatch_handler
135 .find_vma
131 .__lru_cache_del
128 .fget
126 .link_path_walk
115 .do_generic_file_read
113 .pte_alloc_map
113 .filemap_nopage
109 .clear_user_page
106 .fput
104 .__alloc_pages
101 .nr_free_pages