From: "Chen, Kenneth W" <kenneth.w.chen@intel.com>
To: linux-ia64@vger.kernel.org
Subject: RE: should ia64_spinlock_contention do backoff?
Date: Sat, 27 Mar 2004 00:14:13 +0000 [thread overview]
Message-ID: <200403270014.i2R0EFF07014@unix-os.sc.intel.com> (raw)
In-Reply-To: <200403251941.i2PJfrTH026392@napali.hpl.hp.com>
>>>>> Chris Wedgwood wrote on Fri, March 26, 2004 3:41 PM
> Does anyone have any idea what locks are most heavily contented for
> ia64 right now?
This question is a bit too broad, lock contention highly depends on workload.
For example, I'm doing direct I/O on bunch of block devices, and the dev nodes
sit on reiserfs, this contention shows up:
79.7% 91.2% 18us(1415us) 449us( 760ms)(57.9%) 2970234 8.8% 91.2% 0% kernel_flag
0.00% 92.3% 5.8us( 35us) 689us( 58ms)(0.01%) 298 7.7% 92.3% 0% __break_lease+0x80
0.01% 94.3% 23us( 120us) 555us(9106us)(0.01%) 298 5.7% 94.3% 0% chrdev_open+0x1a0
0.00% 83.3% 7.6us( 14us) 73us( 344us)(0.00%) 6 16.7% 83.3% 0% de_put+0x60
0.00% 92.7% 5.4us( 18us) 633us( 14ms)(0.00%) 41 7.3% 92.7% 0% default_llseek+0x60
0.00% 100% 2.9us( 4.2us) 44us( 86us)(0.00%) 2 0% 100% 0% proc_file_lseek+0x60
0.00% 100% 32us( 34us) 2523us(7279us)(0.00%) 3 0% 100% 0% proc_lookup+0x60
0.00% 100% 14us( 17us) 18us( 24us)(0.00%) 2 0% 100% 0% reiserfs_commit_write+0xb0
74.2% 91.2% 16us(1247us) 394us( 292ms)(50.6%) 2959013 8.8% 91.2% 0% reiserfs_dirty_inode+0xa0
0.00% 100% 214us( 214us) 106us( 106us)(0.00%) 1 0% 100% 0% reiserfs_file_release+0x110
0.00% 50.0% 21us( 34us) 29us( 29us)(0.00%) 2 50.0% 50.0% 0% reiserfs_readdir+0xb0
0.01% 92.3% 294us( 369us) 223us(1791us)(0.00%) 13 7.7% 92.3% 0% reiserfs_write_super+0x60
5.5% 92.9% 342us(1415us) 16ms( 760ms)( 7.3%) 10516 7.1% 92.9% 0% schedule+0xe30
0.00% 100% 4.1us( 7.3us) 27us( 45us)(0.00%) 2 0% 100% 0% sys_fcntl+0x430
0.00% 90.9% 14us( 48us) 80us( 254us)(0.00%) 11 9.1% 90.9% 0% sys_ioctl+0xb0
0.00% 93.8% 11us( 21us) 191us(2263us)(0.00%) 16 6.2% 93.8% 0% tty_read+0x170
0.00% 80.0% 17us( 28us) 21us( 38us)(0.00%) 10 20.0% 80.0% 0% tty_write+0x3c0
And if my workload does lots of context switch, load balance also shows up
some hot spots.
1.2% 2.1% 1.9us( 22us) 0us 426680 97.9% 0% 2.1% load_balance+0x290
0.02% 89.3% 2.5us( 44us) 3.3us( 635us)(0.00%) 4582 10.7% 89.3% 0% load_balance+0x2d0
0.02% 1.3% 2.9us( 15us) 2.9us( 8.3us)(0.00%) 4582 98.7% 1.3% 0% load_balance+0x2e0
0.01% 84.6% 2.1us( 17us) 2.9us( 21us)(0.00%) 4585 15.4% 84.6% 0% load_balance+0xb60
- Ken
next prev parent reply other threads:[~2004-03-27 0:14 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-03-25 19:41 should ia64_spinlock_contention do backoff? David Mosberger
2004-03-25 20:06 ` John Hawkes
2004-03-25 22:13 ` Keith Owens
2004-03-25 22:28 ` David Mosberger
2004-03-26 17:16 ` markw
2004-03-26 23:41 ` Chris Wedgwood
2004-03-26 23:44 ` David Mosberger
2004-03-27 0:14 ` Chen, Kenneth W [this message]
2004-03-28 2:37 ` John Hawkes
2004-03-28 19:23 ` Matthew Wilcox
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