Hi Jim,
On Monday 04 February 2008 07:04:10 am Jim Albin wrote:> Hello,
> I''ve seen several notes mentioning the disadvantages of using
disk
> partitions on the storage devices for Lustre OSTs (and/or MDTs). My
> questions, if anyone can help me, are;
>
> 1) Should I delete any existing partitions on the device?
There''s no need to explicitely destroy the partitions if you overwrite
them.
> 2) If not, should I partition the device into a single partition with
> a specific block size (maybe 1mb)?
No need either. One single partition is still a partition.
> 3) Can I just use the disk block device (eg, /dev/sda) when I
> mkfs.lustre and is it
> smart enough to ignore the partition table?
Yes, exactly. Generally speaking, mkfs /dev/sdb will use the whole sdb
device for the filesystem, and you won''t have any partition table. As a
consequence, you won''t be able to boot from it, which is not relevant
here, but all the other operations will work as on any regular
partition (tunefs, mount, etc).
> I''m trying to set up Lustre 1.6.3 and am seeing poor performance,
> possibly fragmentation on the mdt and ost.
> Thanks in advance for any suggestions.
I don''t know what backend hardware you''re using, but in case
of Dell
MD1000s, you probably can give a look (and a try) at:
http://thias.marmotte.net/archives/2008/01/05/Dell-PERC5E-and-MD1000-performance-tweaks.html
HTH,
Cheers,
--
Kilian