Re: RX2800 sporadic disk I/O slowdowns

Am 05.11.2024 um 20:51 schrieb Richard Jordan:

On 11/5/24 10:32 AM, Volker Halle wrote:

Am 18.10.2024 um 20:26 schrieb Richard Jordan:

...
      I have monitor running and have been checking the I/O rates and queue lengths during the 30+ minute runs and the multi-hour runs, and the only diffs there are the overall I/O rates to the two disks are much lower on the long runs than on the normal short ones.

Rich,
did you consider running some disk-IO benchmarking tool ? On the two disks sometimes affected by the problem ? And on other disks on this RAID controller ?
This could provide some baseline achievable I/O rates and response times. You could then run those test while 'the problem' exists and during the 'short runs'.
If you also see the problem with a standard disk-IO benchmark, considerations about local/global buffers may be less important.
There is the DISKBLOCK tool on the Freeware CDs, but I also have a more current version on: https://eisner.decuserve.org/~halle/#diskblock
DISKBLOCK has a 'TEST' command to performance disk performance testing (read-only and/or read-write).
Volker.