Quoting Lars Appel <[log in to unmask]>:

> (manually forwarding from comp.sys.hp.mpe -- gateway not operational?)

gateway at this point is uni-directional (list to comp.sys.hp.mpe)
bi-directional functionality is proving a bit quirky right now - working on
that.

> Hi list,
>
> (a technical question, if on-topic postings are allowed ;-)
>
> We have a situation on a large N-class (4x 750Mhz, 16 GB memory) where
> a couple of jobs using SUPRTOOL to extract data from one or more
> databases have a tendency to put fairly heavy memory demand on the
> system. The symptoms we see is that the user volume set that holds the
> databases shows good throughput (fortunately it has modern LVD disks,
> mirrored and a reasonable spindle count), but the memory demand
> associated with SUPRTOOL making its way through some of the datasets
> (in the 1..n GB size range) results in MPE starting to make room by
> writing out memory regions to transient space on the system volume set,
> which unfortunately cannot keep up with the I/O demand (fewer spindles,
> and older HVD disk array technology) intermittently causing looong disk
> queues and response time degradation...
>
> At present, we are trying to avoid the peaks by at least not running
> more than one of the "big" SUPRTOOL jobs at the same time, but we
> wonder if there are any SUPRTOOL settings that could be helpful to
> somehow "throttle" selected jobs to not be as "greedy" for memory as
> they are at present (e.g. set makeabsent, set prefetch, or set
> privmode).
>
> SUPRTOOL is probably too good at doing its extraction task, at least
> for those jobs that have to "coexist peacefully" with all the
> interactive users (i.e. not inside a batch time window).
>
> Thanks in advance for any advice or pointers.
>
> Lars.

Just a wild guess, but make sure Suprtool's work files are put on the same
volume set as the databases. If you're running Suprtool from the same group
that the databases reside in any working files created should automatically
reside on the same volume set as the group config you're operating from.

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