Your message dated Mon, 04 Aug 2008 18:31:59 +0200
with message-id <[EMAIL PROTECTED]>
and subject line performance decreasing of SCSI controller on kernel
2.6.24-1-amd64
has caused the Debian Bug report #493604,
regarding linux-image-2.6.24-1-amd64: performance decreasing of SCSI controller
on kernel 2.6.24-1-amd64
to be marked as done.
This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
Bug report if necessary, and/or fix the problem forthwith.
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--
493604: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=493604
Debian Bug Tracking System
Contact [EMAIL PROTECTED] with problems
--- Begin Message ---
Package: linux-image-2.6.24-1-amd64
Version: 2.6.24-5
Severity: important
I realised that with new stable kernel 2.6.24-1-amd64 my storage two
times slower than on older stable 2.6.18-6 kernel
my controller :
0e:08.0 SCSI storage controller: LSI Logic / Symbios Logic SAS1068 PCI-X
Fusion-MPT SAS (rev 01)
I measured speed with following command :
2.6.18-6-amd64
dd if=/dev/zero of=/tmp/test count=6500000
6500000+0 records in
6500000+0 records out
3328000000 bytes (3.3 GB) copied, 39.6842 seconds, 83.9 MB/s
2.6.24-1-amd64
dd if=/dev/zero of=/tmp/test count=6500000
6500000+0 records in
6500000+0 records out
3328000000 bytes (3.3 GB) copied, 73.4482 seconds, 45.3 MB/s
sdparm --get WCE /dev/sda on both kernels shows that WCE is enabled .
this behaivior was tested several times .
-- Package-specific info:
-- System Information:
Debian Release: 4.0
APT prefers data
APT policy: (500, 'data'), (500, 'stable')
Architecture: amd64 (x86_64)
Shell: /bin/sh linked to /bin/bash
Kernel: Linux 2.6.18-6-amd64
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Versions of packages linux-image-2.6.24-1-amd64 depends on:
ii debconf [debconf-2.0] 1.5.11etch2 Debian configuration
management sy
ii initramfs-tools [linux-initr 0.85i tools for generating an
initramfs
ii module-init-tools 3.3-pre4-2 tools for managing Linux
kernel mo
--- End Message ---
--- Begin Message ---
Package: linux-image-2.6.24-1-amd64
Version: 2.6.24-5
Tags: wontfix ||||
|
|I've found difference between 2.6.18 and 2.4.24 , I think it is in vm.dirty_background_ratio and vm.dirty_ratio parameters
kernel 2.6.18 has :
vm.dirty_background_ratio = 10
vm.dirty_ratio = 40
and kernel 2.6.24 has :
vm.dirty_background_ratio = 5
vm.dirty_ratio = 10
so , if I will adjust on 2.6.18 this variables to 5 and 10 respectively , I
will get ~40 Megs/s .
it looks like it is not a bug but a feature :)
--- End Message ---
