> echo noop >/sys/block/hdx/queue/scheduler
can this go into /etc/init.d somewhere?
or does that change stick between reboots?
-Whit
On Tue, Apr 28, 2009 at 2:16 PM, Craig James <craig_james@emolecules.com> wrote:
> Kenneth Marshall wrote:
>>>>
>>>> Additionally are there any clear choices w/ regard to filesystem
>>>> types? ?Our choices would be xfs, ext3, or ext4.
>>>
>>> Well, there's a lot of people who use xfs and ext3. XFS is generally
>>> rated higher than ext3 both for performance and reliability. However,
>>> we run Centos 5 in production, and XFS isn't one of the blessed file
>>> systems it comes with, so we're running ext3. It's worked quite well
>>> for us.
>>>
>>
>> The other optimizations are using data=writeback when mounting the
>> ext3 filesystem for PostgreSQL and using the elevator=deadline for
>> the disk driver. I do not know how you specify that for Ubuntu.
>
> After a reading various articles, I thought that "noop" was the right choice
> when you're using a battery-backed RAID controller. The RAID controller is
> going to cache all data and reschedule the writes anyway, so the kernal
> schedule is irrelevant at best, and can slow things down.
>
> On Ubuntu, it's
>
> echo noop >/sys/block/hdx/queue/scheduler
>
> where "hdx" is replaced by the appropriate device.
>
> Craig
>
>
