If AIX briefly utilises paging space for some activity, I often find the utilisation remains high for a while and if I’m monitoring with lsps this means I’ll get a false positive alert.
The following can be used to flush the paging space if you’re sure it’s not being used and there really isn’t a current problem with paging.
In my example, my paging space is on hd6 and lsps reports: –
lsps -a Page Space Physical Volume Volume Group Size %Used Active Auto Type hd6 hdisk1 rootvg 3584MB 57 yes yes lv |
So lets shrink paging by 1LP, this will flush it.
chps -d'1' hd6 shrinkps: Temporary paging space paging00 created. shrinkps: Dump device moved to temporary paging space. |
This bit can take a while – patience – topas will show swapoff process and lsps will show %used of hd6 being used going down, whilst %used of paging00 will be going up.
shrinkps: Paging space hd6 removed. shrinkps: Paging space hd6 recreated with new size. shrinkps: Resized and original paging space characteristics differ, check the lslv command output |
.
Now let’s add the 1LP back again to it’s back up to size.
chps -s'1' hd6 |
This command is much MUCH faster and I’m rewarded by seeing my original paging space %used down to 11%.
lsps -a Page Space Physical Volume Volume Group Size %Used Active Auto Type hd6 hdisk1 rootvg 3584MB 11 yes yes lv |