Re: Linux File system and Oracle setup

andkovacs_at_yahoo.com apparently said,on my timestamp of 9/06/2005 2:44 AM:

> Is this a no sense test case ?

I can't see why. If it is to try and get a clear picture in your mind of where each OS is strong and ho you can take best advantage of each.

> We have a little problem with Linux. Our i/o throughput is lower than
> on windows by 20%. Raid setup is the same on both servers, all disks
> are in Raid 0+1. We think that the issue is related to file system
> setup. At present we are running ext3fs with mode=journaling.
>
> What is the best file linux system for Oracle ?

Do NOT run ext3, and DEFINITELY not with mode=journaling. If anything, it should be mode=writeback. But no, run ext2. Or much better yet: raw. With Windoze, you don't need to go raw: it isn't that much faster.

And DO upgrade to RHAS4: that is based on kernel 2.6 and a LOT better at handling I/O. RHAS3 without a bucketload of patches positively sucks at high speed raw I/O: hits the wall at around 8K IO block size and it's downhill from there.

There is a patch to RH3 that lets it do very large I/O sizes, but the pain in getting it to work with Oracle is a lot worse than simply installing RH4. If you want a Linux without flaws on high volume disk I/O, then go SLES9.

Re-configure the kernel to make sure you don't have stray stuff in there like web servers, nfs, print services, etcetc. Same applies to Windoze, BTW: trim those services!

> At oracle a "boy" advised us to setup our disks in Raid 5 ?! Is there
> something special about Raid and Linux ? Or this boy is just like the
> other average folks at Oracle, really stupid.

Bingo! RAID5 indeed!... I suppose with native controllers and software RAID as well? :)

-- 
Cheers
Nuno Souto
in sunny Sydney, Australia
wizofoz2k_at_yahoo.com.au.nospam