sysgen parameter CHANNELCNT not getting changed

[Jan van den Ende]

Srikanth,

not claiming that our way is the best there is, but here it is anyway:

Each week we run AUTOGEN SAVPARAMS GETDATA at peak time (for most load) on each cluster node (from a scheduled batch job)
Next evening, when the systems tend to be quieter, we run AUTOGEN GENPARAMS SETPARAMS FEEDBACK, generating AGEN$REPORTs in the process.
Next morning we review those reports, and if a trend approaches criticallity we schedule a reboot.
If you are aware of trends, you can prognose values (especially for non-dynamic params) and enter MIN_ or MAX_ values in MODPARAMS, such that reboot needs become rarer and rarer.
Do not expect, nor aim, to get there in one pass!

hth

Proost.

Have one on me.

jpe

[Srikanth Arunachalam]

Hi JPE

Many thanks as usual JPE for your response and this forum has been really good and quick in responding to queries.

Many thanks to everyone and will close the thread with this note.

Regards,
Srikanth

[John Gillings]

Srikanth,

(late response)...

Please be VERY CAREFUL using SYSGEN!

>> SYSGEN> USE ACTIVE
>> SYSGEN> SET CHANNELCNT 2048
>> SYSGEN> WRITE CURRENT

This sequence is very dangerous. You've taken your ACTIVE set and written it back to CURRENT. In many cases that may be benign, but there are a few situations where it could result in an unbootable system. At the very least, you don't know if you're committing some dynamic changes to other parameters since the last reboot to the permanent set.

Please make sure you know EXACTLY which set of parameters you're working with. Personally, I ALWAYS type an explicit USE command in SYSGEN to be certain. Most of the time it would be:

SYSGEN> USE ACTIVE
SYSGEN> ... change some dynamic parameters
SYSGEN> WRITE ACTIVE

OR

SYSGEN> USE CURRENT
SYSGEN> ... change some permanent parameters
SYSGEN> WRITE CURRENT

For permanent parameters, you're MUCH better off making your changes in MODPARAMS and using AUTOGEN to implement them. Changes should document what was done, when, why and by whom. You're also better off using a MIN, MAX or ADD, so that AUTOGEN can take other factors into consideration. Your CHANNELCNT change should look like this in MODPARAMS.DAT:

MIN_CHANNELCNT = 2048 ! Srikanth 27-Oct-2006, required by

[Srikanth Arunachalam]

Hi John,

Thanks for your precise answer. I will follow this when I am changing it for the next time.

Thanks,
Srikanth A