Kit: Thanks for the reply. I was under the impression you create your own version of Lustre and then sell it as a "blackbox" to the customers.
I think Terascala does this, and I would like to figure out exactly what they include in their Lustre offering. TIA On Wed, Apr 15, 2009 at 11:37 PM, Kit Westneat <kwestn...@ddn.com> wrote: > Our storage systems just present as scsi devices either using fc or ib srp. > When we do Lustre installations, we just use whatever is most stable. Most > recently we have been doing a lot of rhel5 based installs, so just use the > sun provided rhel5 lustre kernel. > > - Kit > > ----- Original Message ----- > From: Mag Gam <magaw...@gmail.com> > To: Kit Westneat > Cc: Peter Grandi <pg_...@lus.for.sabi.co.uk>; List Lustre discussion > <lustre-discuss@lists.lustre.org> > Sent: Wed Apr 15 20:11:41 2009 > Subject: Re: [Lustre-discuss] Clarification on DDN performance best practices > > What kernel does DDN use for its products? Or is that a closed secret? > > > On Mon, Apr 13, 2009 at 10:17 AM, Kit Westneat <kwestn...@ddn.com> wrote: >> >>> As to this, the tier are organized as something similar to 8+2 RAID6. >>> For 8-way data, which is the unit? Sectors? Blocks? In other words, what >>> is the stripe data size in KiB with a sector size of 512 vs. a sector >>> size of 4KiB? >>> >> The S2A directRAID6 is actually based on RAID3, so we use byte striping >> instead of block striping. The 4k alignment comes from the physical disk >> sector size of 512-bytes (512 * 8 = 4k). The S2A has a cache segment >> size, which while independent of the LUN sector size, is sort of similar >> in some ways to a block size on a RAID5, though it will never do a >> read-modify-write. The cache size can be set between 128k - 2M, and for >> Lustre, we usually set it to 1 or 2M, since Lustre currently operates >> with 1M messages. >> >> This picture sort of describes from a high level what happens on the >> data path (the text is very marketing heavy unfortunately): >> http://ddn.com/index.php?id=48 >> >> If you are going to be at LUG, DDN will have a fair number folks >> including myself there, feel free to come say hi. We'll also be talking >> at 1 on Friday. >> >> HTH, >> Kit >> >> -- >> --- >> Kit Westneat >> kwestn...@datadirectnet.com >> 812-484-8485 >> >> _______________________________________________ >> Lustre-discuss mailing list >> Lustre-discuss@lists.lustre.org >> http://lists.lustre.org/mailman/listinfo/lustre-discuss >> > _______________________________________________ Lustre-discuss mailing list Lustre-discuss@lists.lustre.org http://lists.lustre.org/mailman/listinfo/lustre-discuss
