Swap is not configured as "strict/contiguous".

[jeevarajkn]

Hi Guru,s

Server- IA,11.23 OS.

We have added 4GB Internal RAM (8GB+4GB) and the current physical memory is 12GB, but still my swap memory utilization is high and above 80%.( Before the memory addition also the swap utilization is above 80%. we have added additional memory to avoid the performance issue as we are going to create one more DB in this server).

Mb Mb Mb PCT START/ Mb
TYPE AVAIL USED FREE USED LIMIT RESERVE PRI NAME
dev 8192 350 7842 4% 0 - 1 /dev/vg00/lvol2
dev 6144 347 5797 6% 0 - 1 /dev/vg00/lvswap
reserve - 11371 -11371
total 14336 12068 2268 84% - 0 -

I have observed that my secondary swap (/de/vg00/lvswap) is not configure as "contiguous" but it is allocated as "strict" and /etc/fstab entry is "/dev/vg00/lvswap ... swap pri=1 0 0".

queries:- As my secondary swap is not configure as "contiguous" is it make any difference in the performance,can we extend my seconadry swap of additional 4GB "online" (without any impact)

Appreciate your repplies.

Thanks
Jeevaraj

[Dennis Handly · Accepted solution]

You don't have a "memory" line so you should do:
kctune swapmem_on=1 # requires reboot

>my secondary swap is not configure as "contiguous"

This shouldn't make a difference since you don't want to swap at all.

[VK2COT]

Hello,

a) Secondary swap does not have to be
contiguous. However, its performance might
be worse as you use blocks all over
the disk.

b) It is a bad idea to have multiple swaps
on the same physical disk(s)!

c) Equally bad is the idea to
have multiple swaps with different size.

HP-UX SNA I course goes into best
practices for swap in detail.

Cheers,

VK2COT

[jeevarajkn]

HI All

I have added another 4 GB of swap, now utilization is normal. Am waiting for the down time change swapmem_on parameter.

Thanks to all.