Hi Jeff,
On 06/23/2010 05:34 AM, Jeff Moyer wrote:
Hi,
Running iozone with the fsync flag, or fs_mark, the performance of CFQ is
far worse than that of deadline for enterprise class storage when dealing
with file sizes of 8MB or less. I used the following command line as a
representative test case:
fs_mark -S 1 -D 10000 -N 100000 -d /mnt/test/fs_mark -s 65536 -t 1 -w 4096 -F
When run using the deadline I/O scheduler, an average of the first 5 numbers
will give you 448.4 files / second. CFQ will yield only 106.7. With
this patch series applied (and the two patches I sent yesterday), CFQ now
achieves 462.5 files / second.
which 2 patches? Could you paste the link or the subject? Just want to
make my test env like yours. ;)
As Joel mentioned in another mail, ocfs2 also use jbd/jbd2, so I'd like
to give it a try and give you some feedback about the test.
Regards,
Tao
This patch set is still an RFC. I'd like to make it perform better when
there is a competing sequential reader present. For now, I've addressed
the concerns voiced about the previous posting.
Review and testing would be greatly appreciated.
Thanks!
Jeff
---
New from the last round:
- removed the think time calculation I added for the sync-noidle service tree
- replaced above with a suggestion from Vivek to only guard against currently
active sequential readers when determining if we can preempt the sync-noidle
service tree.
- bug fixes
Over all, I think it's simpler now thanks to the suggestions from Jens and
Vivek.
[PATCH 1/3] block: Implement a blk_yield function to voluntarily give up the I/O scheduler.
[PATCH 2/3] jbd: yield the device queue when waiting for commits
[PATCH 3/3] jbd2: yield the device queue when waiting for journal commits
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
