topic Re: Swap in Operating System - HP-UX

Swap

George Doller — Wed, 19 Jun 2002 13:23:39 GMT

It looks like my primary swap doesn't get used, even though my 2nd swap hits 100%. Any ideas if this is normal or do I have something set up wrong.
This is the swapinfo output.
1st dev: type=dev, avail=4096, used=2, free=4094, used=0% start/limit=0, reserved=-, pri=1, name=/dev/vg00/lvol2

2nd dev: type=dev, avail=4000, used=3296, free=704, used=82%, start/limit=0, reserved=-, pri=0, name=/dev/vgdev12/lvol1

reserv: avail=-, used=3406, free=-3406

memory: avail=4171, used=2445, free=1726, pct used=59%

total: avail=12267, used=9149, free=3118, pct used=75%

Re: Swap

S.K. Chan — Wed, 19 Jun 2002 13:28:50 GMT

That's simply because your 2ndary swap was set as priority 0 (pri=0) and your primary swap is set at priority 1 (pri=1). So it's a normal behavior for priority 0 swap to be used up first before it starts to use priority 0 swap. It's recommended to set both to the same priority to take advantage of interleave swap.

Re: Swap

James R. Ferguson — Wed, 19 Jun 2002 13:28:52 GMT

Hi George:

The swap priority of your secondary device is higher than the primary, so it would be given preference. Set your priority to the same value to interleave I/O and achieve the best performance.

Regards!

...JRF...

Re: Swap

PIYUSH D. PATEL — Wed, 19 Jun 2002 13:31:00 GMT

Hi,

The secondary swap space has a higher priority - 0 then the primary swap (1).

Set both the swaps to the same priority for I/O interleaving and better performance.

Piyush

Re: Swap

Sanjay_6 — Wed, 19 Jun 2002 13:36:59 GMT

Hi,

check out the priority of your 2nd swap. It is set at a higher priority than the 1st.

http://support1.itrc.hp.com/service/cki/docDisplay.do?docLocale=en_US&docId=200000048595137

Hope this helps.

Regds