Re: file system and raid performance

On Thu, Aug 7, 2008 at 3:57 PM, Andrej Ricnik-Bay
<andrej.groups@gmail.com> wrote:
> 2008/8/8 Scott Marlowe <scott.marlowe@gmail.com>:
>> noatime turns off the atime write behaviour.  Or did you already know
>> that and I missed some weird post where noatime somehow managed to
>> slow down performance?
>
> Scott, I'm quite aware of what noatime does ... you didn't miss a post, but
> if you look at Mark's graphs on
> http://wiki.postgresql.org/wiki/HP_ProLiant_DL380_G5_Tuning_Guide
> they pretty much all indicate that (unless I completely misinterpret the
> meaning and purpose of the labels), independent of the file-system,
> using noatime slows read/writes down (on average).

Interesting.  While a few of the benchmarks looks noticeably slower
with noatime (reiserfs for instance) most seem faster in that listing.

I am just now setting up our big database server for work and noticed
a MUCH lower performance without noatime.