Re: 2.5.38-mm2 dbench $N times

William Lee Irwin III
2002-09-25T00:35:40Z

William Lee Irwin III wrote:
>> Not sure. This is boot bay SCSI crud, but single-disk FC looks
>> *worse* for no obvious reason. Multiple disk tests do much better
>> (about matching the el-scruffo PC numbers above).
>>

On Tue, Sep 24, 2002 at 05:31:39PM -0700, Andrew Morton wrote:
> dbench 16 on that sort of machine is a memory bandwidth test.
> And a dcache lock exerciser. It basically doesn't touch the
> disk. Something very bad is happening.
> Anton can get 3000 MByte/sec ;)

Hmm, this is odd (remember, dcache_rcu is in here):

c01053dc 9194801 60.668 poll_idle
c01175db 1752528 11.5633 .text.lock.sched
c0114c08 1281763 8.45717 load_balance
c0106408 388517 2.56346 .text.lock.semaphore
c0147a4e 272571 1.79844 .text.lock.file_table
c0115080 265006 1.74853 scheduler_tick
c0132374 227403 1.50042 generic_file_write_nolock
c0115434 187759 1.23885 do_schedule
c01233c8 167905 1.10785 run_timer_tasklet
c0114778 103077 0.68011 try_to_wake_up
c010603c 100121 0.660606 __down
c0111788 96062 0.633824 smp_apic_timer_interrupt
c011fa20 70840 0.467408 tasklet_hi_action
c011f700 63125 0.416504 do_softirq
c0131880 60640 0.400107 file_read_actor
c0145dd0 53872 0.355452 generic_file_llseek
c01473e0 45819 0.302317 get_empty_filp
c0175190 35814 0.236304 ext2_new_block
c01476ac 31657 0.208875 __fput
c0146354 26755 0.176532 vfs_write
c010d718 26627 0.175687 timer_interrupt
c01a2cd0 26426 0.174361 atomic_dec_and_lock
c0123294 23022 0.151901 update_one_process