On Wed, 2007-02-28 at 02:08 -0600, Johnny Hughes wrote:
On Tue, 2007-02-27 at 21:10 -0500, Ross S. W. Walker wrote:
-----Original Message----- From: centos-devel-bounces@centos.org [mailto:centos-devel-bounces@centos.org] On Behalf Of Ross S. W. Walker Sent: Sunday, February 25, 2007 12:24 PM To: centos-devel@centos.org Subject: [CentOS-devel] Back-port md raid1/10 BIO_RW_SYNC patch for DRBD
Attention CentOS Developers,
Here is a back-port of Lars Ellenberg's md raid1/10 patch from 2.6.19+ to 2.6.9. It seems the md raid1 and raid10 drivers were stripping the BIO_RW_SYNC flags on requests which caused a severe performance penalty for DRBD when writing it's meta-data to these volumes.
The patch is attached as well as inlined:
No comments?
I just put it in the new CentOSPlus kernel (that I am currently testing).
Should be out later today (if it works).
OK ... the released CentOS-Plus kernel (2.6.9-42.0.10.plus.c4) has that patch installed on x86_64 and i386 ... and I did install it and test with DRBD. The systems it is on are running OK.
Thanks, Johnny Hughes