The concurrency I'm aware of is at the hdisk/lun level. There's a num_cmd_elems at on the fcs adapter which we set to 2k, and then queue_depth on the hdisk. That's why spreading I/O across as many hdisks/luns as possible is advantageous.
Rick -----Original Message----- From: ADSM: Dist Stor Manager [mailto:ADSM-L@VM.MARIST.EDU] On Behalf Of Huebner, Andy Sent: Wednesday, July 15, 2015 9:33 AM To: ADSM-L@VM.MARIST.EDU Subject: Re: Disk layout for AIX He claims there is a queuing issue with too many at the HBA. I guess I missed that the last 12 years of being a storage/TSM admin. I told him the theory of using many was to allow more concurrency. Before we build I just want make sure this is not a mistake that cannot be easily fixed. Thanks, Andy Huebner -----Original Message----- From: ADSM: Dist Stor Manager [mailto:ADSM-L@VM.MARIST.EDU] On Behalf Of David Ehresman Sent: Wednesday, July 15, 2015 8:12 AM To: ADSM-L@VM.MARIST.EDU Subject: Re: [ADSM-L] Disk layout for AIX VGs are cheap. Why does your AIX admin want to reduce the number of VGs? David Ehresman -----Original Message----- From: ADSM: Dist Stor Manager [mailto:ADSM-L@VM.MARIST.EDU] On Behalf Of Huebner, Andy Sent: Wednesday, July 15, 2015 9:03 AM To: ADSM-L@VM.MARIST.EDU Subject: [ADSM-L] Disk layout for AIX I have an AIX admin that wants to build my new TSM server using two VGs for the database (6 file systems) and one VG for the various logs. We currently have 6 VGs for the DB and 3 VGs for the logs. Each VG contains 1 file system. The DB is about 375GB and the new hardware is a P8. No TSM de-dup. Should I be concerned about the DB setup? Andy Huebner ----------------------------------------- The information contained in this message is intended only for the personal and confidential use of the recipient(s) named above. If the reader of this message is not the intended recipient or an agent responsible for delivering it to the intended recipient, you are hereby notified that you have received this document in error and that any review, dissemination, distribution, or copying of this message is strictly prohibited. If you have received this communication in error, please notify us immediately, and delete the original message.
