Subject: disk write performance with softdep
To: None <current-users@NetBSD.org>
From: Kouichirou Hiratsuka <hira@po6.nsk.ne.jp>
List: tech-kern
Date: 04/09/2006 18:27:42
Hello,
On my machine (ThinkPad X32), disk write performance with softdep
is about 4 times as slow as before. It takes about 3 or 4 times
as long to copy the files. And with bonnie++, the sequential
output (per char) is 1/4.
It seems to be related to this commit (please see the following
results of bonnie++).
http://mail-index.NetBSD.org/source-changes/2006/03/30/0021.html
bonnie++ by 2006-03-30 12:00 UTC GENERIC kernel (with softdep):
-------------------------------------------------------------------------------
Version 1.03 ------Sequential Output------ --Sequential Input- --Random-
-Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP
firefly.locald 300M 44458 68 46395 20 44065 19 62603 99 +++++ +++ +++++ +++
------Sequential Create------ --------Random Create--------
-Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP
16 3294 95 +++++ +++ +++++ +++ 2280 65 5287 97 11461 97
-------------------------------------------------------------------------------
bonnie++ by 2006-03-30 13:00 UTC GENERIC kernel (with softdep):
-------------------------------------------------------------------------------
Version 1.03 ------Sequential Output------ --Sequential Input- --Random-
-Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP
firefly.locald 300M 11288 25 46092 20 42042 18 59944 94 +++++ +++ +++++ +++
------Sequential Create------ --------Random Create--------
-Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP
16 3106 92 +++++ +++ +++++ +++ 3500 92 4868 99 10719 99
-------------------------------------------------------------------------------
Anyone else seeing this?
--
Kouichirou Hiratsuka
hira@po6.nsk.ne.jp