Topic
  • 3 replies
  • Latest Post - ‏2012-04-19T05:40:44Z by wra_suva
SystemAdmin
SystemAdmin
1188 Posts

Pinned topic TSM upgrade from 5.5 to 6.2 slow

‏2010-10-14T00:05:43Z |
Hi

I've got a new Power7 710 machine and doing insertdb with a exported TSM db from another machine. All steps go as planed but when doing the importdb I get 1MB/s the other two phases of the importdb run at around 12MB/s. This is a 16Core machine with 16GB memory, the load is done from one Raid10 DS4300 to another Raid10 DS4300, Raid10 with 12 disks. Has anyone seen such slow IO on the first phase of ImportDB ? One hint is that I've got the following in db2diag:

2010-10-13-23.47.12.047863+000 I506074A498 LEVEL: Warning
PID : 1011792 TID : 93213 PROC : db2sysc 0
INSTANCE: db2lsh1 NODE : 000 DB : TSMDB1
APPHDL : 0-973 APPID: *LOCAL.db2lsh1.101013235617
AUTHID : DB2LSH1
EDUID : 93213 EDUNAME: db2lrid 0
FUNCTION: DB2 UDB, database utilities, DIAG_NOTE, probe:0
DATA #1 : String, 81 bytes
LOADID: 34359.2010-10-13-23.47.11.740940.0 (2;148)
Load CPU parallelism is: 15, 0
But only 4 of the cores do any work during the import. I'm hoping someone has seen this before, but also if you know how to decrease the "CPU paralleism" in DB2 let me know how to do it, I found several articles about LOAD in DB2 with SAP running slow if you got more than 4 cores.

Kind Regards
Stefan Thor Hreinsson
basis
Updated on 2012-04-19T05:40:44Z at 2012-04-19T05:40:44Z by wra_suva
  • SystemAdmin
    SystemAdmin
    1188 Posts

    Re: TSM upgrade from 5.5 to 6.2 slow

    ‏2010-10-15T23:13:04Z  
    Update on this, we've finished my update from 5.5 to 6.2.1 :) The upgrade took 24 hours in total on a P710 Power7 AIX 6.1 TL4 SP3 with the iocp bug fix installed. While waiting we tried the exact same update on á p505 AIX 5.3 TL11 machine with 2GB memory and DS3500 SATA Raid5 disks, first phase on that machine was pulling 12MB/s against 4.4MB/s on Power7 Raid10.

    To me it's astounding, a rperf 4 machine outperformed a rperf 40 machine and in combination we could say SATARaid5 outperformed SASRaid10. Something is amiss on Power7 AIX6.1 TSM 6.2.1.

    I've done the same 5.5 to 6.2.1 upgrade on several Linux machines and they have pulled 30MB/s on phase one, disks or raid setup on them is not better than on the Power7 machine, and these are x3650 first gen, really old Intel machines :)

    I'll keep on searching for a reason since I hate unexplained problems, but got this feeling it's AIX <-> POWER7 <-> DB2 problem, now just wish the web support portal and passport sites would stop giving me 404 errors :(

    Kind Regards
    Stefan Thor Hreinsson
    Basis
  • dcskinner
    dcskinner
    1 Post

    Re: TSM upgrade from 5.5 to 6.2 slow

    ‏2012-03-28T21:43:49Z  
    Update on this, we've finished my update from 5.5 to 6.2.1 :) The upgrade took 24 hours in total on a P710 Power7 AIX 6.1 TL4 SP3 with the iocp bug fix installed. While waiting we tried the exact same update on á p505 AIX 5.3 TL11 machine with 2GB memory and DS3500 SATA Raid5 disks, first phase on that machine was pulling 12MB/s against 4.4MB/s on Power7 Raid10.

    To me it's astounding, a rperf 4 machine outperformed a rperf 40 machine and in combination we could say SATARaid5 outperformed SASRaid10. Something is amiss on Power7 AIX6.1 TSM 6.2.1.

    I've done the same 5.5 to 6.2.1 upgrade on several Linux machines and they have pulled 30MB/s on phase one, disks or raid setup on them is not better than on the Power7 machine, and these are x3650 first gen, really old Intel machines :)

    I'll keep on searching for a reason since I hate unexplained problems, but got this feeling it's AIX <-> POWER7 <-> DB2 problem, now just wish the web support portal and passport sites would stop giving me 404 errors :(

    Kind Regards
    Stefan Thor Hreinsson
    Basis
    I know this is an old post, but it was helped us track down the problem and incase anyone else finds it, here is the fix.

    We were experiencing the same issues. It looks like we have tracked this down to the Olson Timezone format on AIX6.1. Switching to POSIX TZ seems to have resolved the issue. We are seeing 10x better performance during the insert phase of the INSERTDB process. (between 2G/hr and 4G/hr with Olson and 30-50G/hr with POSIX).
  • wra_suva
    wra_suva
    1 Post

    Re: TSM upgrade from 5.5 to 6.2 slow

    ‏2012-04-19T05:40:44Z  
    • dcskinner
    • ‏2012-03-28T21:43:49Z
    I know this is an old post, but it was helped us track down the problem and incase anyone else finds it, here is the fix.

    We were experiencing the same issues. It looks like we have tracked this down to the Olson Timezone format on AIX6.1. Switching to POSIX TZ seems to have resolved the issue. We are seeing 10x better performance during the insert phase of the INSERTDB process. (between 2G/hr and 4G/hr with Olson and 30-50G/hr with POSIX).
    Hello
    Thanks a lot for your solution. I had the same Problem. The insert prozess on TSM Upgrade was versy slow (4 GB/Std). We had to change the timzone, because with the old timezone not all system changed time. Some day after changed TZ i wanted migrate an second TSM Server.
    I was really confused that on a same System (P740) the migration process was so slow. No i changed TZ back, an the insert prozess is fast (45 GB /Std). Thank's.