Re: LTO Fibre tape performance under AIX 5.1
>We are installing a new TSM server on a pSeries 650 using TSM >5.1.6.5, and a 3584 Tape Library with a L32 and D32 frames with 15 LTO >Gen 1 Tape drives. The 650 has 4 2Gb/sec FC ports; two go one McData >Spherion 4500 switch, and to go to another. Half the tape drives are go >to one Spherion switch, and half to the other. We have them zoned so >that each FC adapter can only see 3 or 4 drives. >Our problem is that we can't get the LTO performance where it >belongs. A typical backup from the 650 itself using shared memory (or >not) only gets 5-6 MB/Sec. About the same for a Giga-bit network AIX >client with no other load. >Even a "MOVE DATA" tape-to-tape maxes out at 8 MB/sec. In this >test, we made sure the two tape drives involved were on different FC >adapters, on different Spherion switches, and the 650 was otherwise >idle, so there should have been no contention anywhere. It took 45 >minutes to copy 21GB. Not very good. >The 3584 firmware is v3060, the 3580 firmware is v3481, both the >latest. The 650, the 6228 (FC adapter) microcodes are also the latest. > The problem seems to be the same for all the drives. We have bumped up >the dsmserv.opt options to appropriately high levels according to the >Performance Guide. We think we have not overlooked anything there. Your posting doesn't make note of it, but we had an extensive List discussion of LTO performance at the end of last week. Your "typical backup" rates look like those in the chart on page 12 of ftp://ftp.software.ibm.com/software/tivoli/whitepapers/wp-tsm-lto.pdf . You don't specify what server options you boosted, but observe what the paper has to say about TXN* options. I would, however, expect your in-server operations to proceed faster. You don't say if you performed essential pre-TSM-usage benchmark tests, outside of TSM, to gather baseline numbers before using the drives under TSM in validating their performance thusly first: I would do that. You may have path serialization issues. Richard Sims, BU
[Fwd: LTO Fibre tape performance under AIX 5.1]
As a followup to my earlier message, one issue that came up is the TSM database and logs are on the same disks. In other words, we have the first copy of the database and the log on one disk, and the database mirror and log mirror on another disk. They are all using separate filesystems. I don't think this will perform well, but the system admin that set up the system insists on them that way because he doesn't want to use the root volume group to hold the logs (the system only has 4 drives today, two for rootvg, and two for TSM stuff). In a few weeks we are supposed to be getting some SSA drives, but have to make do until then. Would having a 9GB database and 1GB log on the same disk cause inordinate seek times? The server is in test now, with only a couple clients on it, so they are only a few percent utilized. John Original Message Subject: LTO Fibre tape performance under AIX 5.1 Date: Mon, 16 Jun 2003 13:42:10 -0500 From: John Schneider <[EMAIL PROTECTED]> Reply-To: [EMAIL PROTECTED] To: ADSM: Dist Stor Manager <[EMAIL PROTECTED]> Greetings, We are installing a new TSM server on a pSeries 650 using TSM 5.1.6.5, and a 3584 Tape Library with a L32 and D32 frames with 15 LTO Gen 1 Tape drives. The 650 has 4 2Gb/sec FC ports; two go one McData Spherion 4500 switch, and to go to another. Half the tape drives are go to one Spherion switch, and half to the other. We have them zoned so that each FC adapter can only see 3 or 4 drives. Our problem is that we can't get the LTO performance where it belongs. A typical backup from the 650 itself using shared memory (or not) only gets 5-6 MB/Sec. About the same for a Giga-bit network AIX client with no other load. Even a "MOVE DATA" tape-to-tape maxes out at 8 MB/sec. In this test, we made sure the two tape drives involved were on different FC adapters, on different Spherion switches, and the 650 was otherwise idle, so there should have been no contention anywhere. It took 45 minutes to copy 21GB. Not very good. The 3584 firmware is v3060, the 3580 firmware is v3481, both the latest. The 650, the 6228 (FC adapter) microcodes are also the latest. The problem seems to be the same for all the drives. We have bumped up the dsmserv.opt options to appropriately high levels according to the Performance Guide. We think we have not overlooked anything there. Any suggestions certainly appreciated. John Schneider *** * John D. Schneider Email: [EMAIL PROTECTED] * Phone: 636-492-0247 * Lowery Systems, Inc. * 1329 Horan Disclaimer: Opinions expressed here are * Fenton, MO 63026 mine and mine alone. *** -- John Schneider *** * John D. Schneider Email: [EMAIL PROTECTED] * Phone: 636-492-0247 * Lowery Systems, Inc. * 1329 Horan Disclaimer: Opinions expressed here are * Fenton, MO 63026 mine and mine alone. ***
LTO Fibre tape performance under AIX 5.1
Greetings, We are installing a new TSM server on a pSeries 650 using TSM 5.1.6.5, and a 3584 Tape Library with a L32 and D32 frames with 15 LTO Gen 1 Tape drives. The 650 has 4 2Gb/sec FC ports; two go one McData Spherion 4500 switch, and to go to another. Half the tape drives are go to one Spherion switch, and half to the other. We have them zoned so that each FC adapter can only see 3 or 4 drives. Our problem is that we can't get the LTO performance where it belongs. A typical backup from the 650 itself using shared memory (or not) only gets 5-6 MB/Sec. About the same for a Giga-bit network AIX client with no other load. Even a "MOVE DATA" tape-to-tape maxes out at 8 MB/sec. In this test, we made sure the two tape drives involved were on different FC adapters, on different Spherion switches, and the 650 was otherwise idle, so there should have been no contention anywhere. It took 45 minutes to copy 21GB. Not very good. The 3584 firmware is v3060, the 3580 firmware is v3481, both the latest. The 650, the 6228 (FC adapter) microcodes are also the latest. The problem seems to be the same for all the drives. We have bumped up the dsmserv.opt options to appropriately high levels according to the Performance Guide. We think we have not overlooked anything there. Any suggestions certainly appreciated. John Schneider *** * John D. Schneider Email: [EMAIL PROTECTED] * Phone: 636-492-0247 * Lowery Systems, Inc. * 1329 Horan Disclaimer: Opinions expressed here are * Fenton, MO 63026 mine and mine alone. ***
