I did some measurement, because we're going to use SAN for large "user data" (notably databases and such). Certain operations were at least twice as fast (wall clock) via SAN compared to [E]CKD. SAN performed so well in terms of speed that even with EDEV overhead it was nearly as fast as CKD. (To be clear, that's three things tested: direct SAN, SAN via EDEV, and CKD.)
The critical piece I have not yet figured out is multipath. We need dual paths for the when-not-if our SAN guys knock over half the fabric for maint (as well as the usual redundancy we've come to expect from mainframe systems, Linux or otherwise). Naturally, increased bandwidth with simultaneous traffic would be most welcome, but right now a simple round-robin providing fail-over and fail-back would be nice. -- R; Marcy Cortes <[EMAIL PROTECTED]> Sent by: Linux on 390 Port <[email protected]> 09/07/2006 08:41 PM Please respond to Linux on 390 Port <[email protected]> From Marcy Cortes <[EMAIL PROTECTED]> To [email protected] cc Subject Disks for DB2 - San vs. big 3390s Some folks here want to run DB2 databases on z/Linux. I think we need something bigger than 3390 mod 9 for databases (I think using LVM across more than say 8 disks is a pita and have told them 50G is as big as they can have :). The z/OS guys want to give us mod 54's like they have. I've been pushing for LUNs. What say ye performance experts about 54's? Can we even us those for z/Linux (sles9x - z/VM 5.2). Marcy Cortes "This message may contain confidential and/or privileged information. If you are not the addressee or authorized to receive this for the addressee, you must not use, copy, disclose, or take any action based on this message or any information herein. If you have received this message in error, please advise the sender immediately by reply e-mail and delete this message. Thank you for your cooperation." ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
