Results 1 to 2 of 2
  1. #1
    Join Date
    Nov 2003

    Exclamation Unanswered: Slow load of ASE database on HP-UX 11.00

    I have a case where in a 21 GB database loads in approximately 15 minutes on one machine and the same database takes about 45 to 75 minutes on another machine which is configured almost identically. The database has 5 devices which are striped across 4 disks with at 64KB stripe size. Each disk in the volume group is 18 GB capacity. I have noticed that larger disks slow down the performance. What could be different in the two machines to have such a large difference in performance!!! I have check the following Kernel parameters, Sybase config files, disk firmware, disk array firmware and driver versions.. They are all the same. The only major difference between the two machines being that one has about 40 disks on it and the other has about 20 disks. However, there are not more than 5 disks on a controller, and the volume group is spread across different controllers. There is no mirroring of any kind taking place on either machines..

    I don't know if I am missing something, but it seems obvious that I am. When I look at the sar -u output, I see horrendous %wio for the slower machine (numbers average around 85). For the load of the identical database on the the faster machine the %wio is around 15. Also, when I do a sar -d, I notice that the avque on the slower machine never goes beyond 1, where as on the faster machine, the numbers are way over 10. There is a significant difference in the r+w/s and the blks/s also.

    Can someone help me figure out the bottleneck.

    Thanks in advance.

  2. #2
    Join Date
    Nov 2002
    Try a sp_sysmon "00:15:00", diskio in both machines during the backup process

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts