Steve, Thanks to you and the others who took a crack at our problem. After remounting the LOG with the dio flag, EXPIRATION has dropped from 6-8 days to 15 hours. But nothing we've tried has had any effect on the lag on DB backups. Whether FULL or INCR there is still a lengthy delay between tape mount and first write.
Fred Johanson TSM Administrator University of Chicago 773-702-8464 -----Original Message----- From: ADSM: Dist Stor Manager [mailto:ads...@vm.marist.edu] On Behalf Of Steven Harris Sent: Thursday, January 22, 2009 7:40 PM To: ADSM-L@VM.MARIST.EDU Subject: Re: [ADSM-L] Strange behavior on DB(?) or Log(?) Fred, Mounting the filesystems containing DB and log with the dio flag can make a huge performance difference on AIX. It bypasses all the AIX read forward and write behind stuff. Just don't trust topas afterward as it bypasses the stats there as well. Regards Steve Steven Harris TSM admin, Sydney Australia Mark Stapleton <mark.staple...@c DW.COM> To Sent by: "ADSM: ADSM-L@VM.MARIST.EDU Dist Stor cc Manager" <ads...@vm.marist Subject .EDU> Re: [ADSM-L] Strange behavior on DB(?) or Log(?) 22/01/2009 11:07 AM Please respond to "ADSM: Dist Stor Manager" <ads...@vm.marist .EDU> From: ADSM: Dist Stor Manager [mailto:ads...@vm.marist.edu] On Behalf Of Fred Johanson We've got two machines which are identical in every way, same hardware, same AIX, same TSM level, same options set, same storage pools, domains, everything except one has the DB and Log on local disk. On this box things run very slowly: expiration may take a week, filespace deletion creeps, and we see this as the normal behavior All of the operations you describe above involve database and log transactions. Since you've eliminated everything else, I would suspect you've got substandard local disk (or possibly a corrupt database). Since correcting a possible database issue will take a good deal of time and effort, have you given thought to trying something easier, such as putting the dbvols and logvols on SAN- or iSCSI-attached disk? -- Mark Stapleton System engineer, CDW No virus found in this outgoing message. Checked by AVG. Version: 7.5.552 / Virus Database: 270.10.10/1905 - Release Date: 1/20/2009 2:34 PM
