increasing device swap

[akarayil]

Hi experts,
we have a rx4640(hp 11.23)with 16GB memory. Two swap LVs, with 4GB each(total 8GB), are configured in the same PV(I know that this is not recommended). I've a 73GB free disk.
I want to increase the swap using space from the other disk.
my question is, should I extend the vg00 using the free disk and create LV for swap(I feel this is better) or create new LV for swap on new VG?
size should be 4GB or 8GB?
As the size of primary swap is 4GB, I think the same size is better.
Can you give me the best option?

with thanks and regards,

[Kenan Erdey]

hi,

try this link:

http://forums11.itrc.hp.com/service/forums/questionanswer.do?threadId=962784

and if you have pseudo swap you may not need much swap area.

Kenan.

[Venkatesh BL]

> As the size of primary swap is 4GB, I think the same size is better.

They don't need to be of same size, as they are not related to each other as such. During low memory condition, the paging routine would use up the primary swap device and then go to the secondary swap device.

[akarayil]

On 17th night, one critical system process was terminated because of shortage of memory. Thats why I tried to increase the swap. But the problem was solved by changing dbc_max_pct kernal parameter value from 50 to 15.

Thank you for all your valuable suggestions

[Dennis Handly]

>But the problem was solved by changing dbc_max_pct kernel parameter value from 50 to 15.

It still might be useful for you to provide your "swapinfo -tam" output.

[akarayil]

Hi,

> It still might be useful for you to provide >your "swapinfo -tam" output.

#swapinfo -tam
Mb Mb Mb PCT START/ Mb
TYPE AVAIL USED FREE USED LIMIT RESERVE PRI NAME
dev 4096 8 4088 0% 0 - 1 /dev/vg00/lvol2
dev 4096 8 4088 0% 0 - 1 /dev/vg00/lvol9
reserve - 5314 -5314
memory 18420 3824 14596 21%
total 26612 9154 17458 34% - 0 -

regards

[Dennis Handly]

>total 26612 9154 17458 34% - 0 -

Now you have only 34% used. If you expect to add a lot more activity on the system, you may need more swap.

[akarayil]

Hi,
Once again I faced the same problem.To prevent the process from being terminated, I think, I should increase the swap.
So, for better performance, What swap size should I enable on other disk?

Regards,

[Venkatesh BL]

Try to add single largest free disk as additional swap.