Joshua, The db and log are spread out among 8 Logical Subsystems.
Eliza > > Eliza, > > How many ranks (Logical Subsystems) is your DB and log spread out > across? For highest performance, try spreading the load across as many > spindles as possible. > > -- > Joshua S. Bassi > IBM Certified - AIX 4/5L, SAN, Shark > Tivoli Certified Consultant - ADSM/TSM > eServer Systems Expert -pSeries HACMP > > AIX, HACMP, Storage, TSM Consultant > Cell (831) 595-3962 > [EMAIL PROTECTED] > > > -----Original Message----- > From: ADSM: Dist Stor Manager [mailto:[EMAIL PROTECTED]] On Behalf Of > Eliza Lau > Sent: Wednesday, September 18, 2002 9:28 AM > To: [EMAIL PROTECTED] > Subject: backup performance with db on the Shark ESS > > I posted a message a month ago about performance degradation after > moving > the db and the log to the Shark ESS. The problem has been resolved with > help from Paul Seay. Here is a recap: > > Moved 32G db and 10G log from attached SCSI non-RAID disks to IBM Shark > ESS. > Kept 2 copies of db and log. I wasn't ready to drop the security > blanket. > Backup db increased from 40 minutes to 90 minutes. > Reformat the AIX volume group that the db was on from 2 LUNs to 8 LUNs. > Backup db still ran for 90 minutes. The additional LUNs didn't help at > all. > Dropped the second copy of the db and log. > Backup db now runs for 24 minutes. > > Paul told me that there is a fix in 4.2.2.8 for performance of backing > up > 2 copies of the db. I will try setting up a second copy of the db after > I > upgrade to 5.1 in a few months and see if it makes a difference. > Meanwhile, I am keeping only 1 copy of the db and 2 copies of the log > and depending solely on RAID-5 of the ESS for the integrity of my db. > > > server: TSM 4.2.1.15 on AIX 4.3.3 > > Thanks to all the people who contributed, > > Eliza Lau > Virginia Tech Computing Center > 1700 Pratt Drive > Blacksburg, VA 24060 > [EMAIL PROTECTED] >
