Re: Maximum Java Heap Size/OpenVMS Java Experiences?

In article <qP7ui.11989$J13.5284@trnddc02>, John Santos <john@xxxxxxx>
wrote:

P. Sture wrote:
In article <tZQti.5637$J13.5449@trnddc02>, John Santos <john@xxxxxxx>
wrote:


P. Sture wrote:

In article <1185990365.187329.66340@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
sean@xxxxxxxxxx wrote:



Out of sheer curiosity and thinking it would be easy, I tried to find
in the on-line documentation what the current maximum WSMAX value is,
since it looks like that's the next limit.


If you do:

$ MCR SYSGEN SHOW WSMAX

you get something like this (taken on V8.3, Alpha)


Parameter Name Current Default Min. Max. Unit Dynamic
-------------- ------- ------- ------- ------- ---- -------
WSMAX 393216 8192 1024 134217728 Pagelets
internal value 24576 512 64 8388608 Pages

$ write sys$output 134217728/2048 ! max in megabytes
65536

i.e. 64 GB, for Alpha running V8.3. You should repeat this on Itanium
to check that SYSGEN uses the same maximum value there.


On I64 V8.3:

$ mcr sysgen show wsmax
Parameter Name Current Default Min. Max. Unit
Dynamic
-------------- ------- ------- ------- ------- ----
-------
WSMAX 1089536 131072 16384 134217728 Pagelets
internal value 68096 8192 1024 8388608 Pages

Same maximum, but much higher default and min values. "Current" value came
from AUTOGEN with feedback, AFAIK.



Thanks for that. Ditto here for the "Current" vaalue. Surprisingly, I
don't see anything (on Alpha) about WSMAX in
SYS$SYSTEM:AGEN$PARAMS.REPORT, though AUTOGEN is obviously calculating
it.


The same on Itanium. I didn't set it explicitly, and there's nothing
in MODPARAMS.DAT or in AGEN$PARAMS.REPORT. My rx2620 came from the
porting workshop, and was pre-loaded with V8.2-1 (since upgraded to V8.3).
Maybe HP set it, or maybe AUTOGEN set it on the initial install and
the report is long gone.

A look at AUTOGEN shows that it does check to see whether WSMAX is too
large or too small, and there's a lot of code there; parameters
affecting fluid memory are taken into account to ensure there is enough
of that.

Looking back at my upgrade to V8.3, WSMAX wasn't in MODPARAMS.DAT
generated by the upgrade procedure, nor the accompanying
AGEN$PARAMS.REPORT (or any since).

WSMAX isn't included in AGEN$HISTORY.DAT either, so I conclude that it
is calculated by AUTOGEN each time it is run.

--
Paul Sture

Sue's OpenVMS bookmarks:
http://eisner.encompasserve.org/~sture/ovms-bookmarks.html
.

Relevant Pages

  • Re: Maximum Java Heap Size/OpenVMS Java Experiences?
    ... in the on-line documentation what the current maximum WSMAX value is, ... $ MCR SYSGEN SHOW WSMAX ... you get something like this (taken on V8.3, Alpha) ... or maybe AUTOGEN set it on the initial install and ...
    (comp.os.vms)
  • Re: Maximum Java Heap Size/OpenVMS Java Experiences?
    ... in the on-line documentation what the current maximum WSMAX value is, ... $ MCR SYSGEN SHOW WSMAX ... you get something like this (taken on V8.3, Alpha) ... Ditto here for the "Current" vaalue. ...
    (comp.os.vms)