topic Re: Swap1 volume? in Operating System - HP-UX

Swap1 volume?

Leam Hall — Tue, 08 Feb 2011 11:36:47 GMT

Trying to clean up an old server and consolidate the 50+ volume groups some ninny set up. In sam, vg01 shows:

ecc vg01 LVM Unused 512 0
lvol9 vg01 LVM Unused 8192 0
swap1 vg01 LVM Swap 8192 0

And /etc/fstab shows this for vg01:

grep vg01 /etc/fstab
/dev/vg01/swap1 ... swap pri=0 0 0

So it looks like I have 8 GB of disk swap space in vg01 and 8GB unused. However, vmstat -n shows:

avm -> 956994
free -> 26017

So do I really have disk swap enabled properly?

Thanks!

Leam

Re: Swap1 volume?

Rita C Workman — Tue, 08 Feb 2011 12:04:56 GMT

I generally just run swapinfo -tam for my verification of active swap.

That active virtual pages and free list size, is just too much math for me.

Regards,
Rita

Re: Swap1 volume?

Leam Hall — Tue, 08 Feb 2011 12:12:55 GMT

Awesome!

swapinfo -tam
Mb Mb Mb PCT START/ Mb
TYPE AVAIL USED FREE USED LIMIT RESERVE PRI NAME
dev 4096 0 4096 0% 0 - 1 /dev/vg00/lvol2
dev 8192 909 7283 11% 0 - 0 /dev/vg01/swap1
reserve - 3851 -3851
memory 6304 4154 2150 66%
total 18592 8914 9678 48% - 0 -

So I should be able ot remove vg01 and use the space for filesystems. It looks like vg00/lvol2 is large enough. Of course, that one isn't mentioned in /etc/fstab. Looks like I need to add it, right?

Leam

Re: Swap1 volume?

hvhari — Tue, 08 Feb 2011 12:13:20 GMT

swapinfo is the command to check about swap actual usage. The above shows just the logical volume names in vg01.

Re: Swap1 volume?

Rita C Workman — Tue, 08 Feb 2011 12:16:33 GMT

I wouldn't do that. Additional swap is needed for the system to run properly. So leave it where it is.
Albeit, I generally put my additional swap right into vg00, thus saving a minor number.
But to each his own...

What exactly is lvol9 connected with?
Run bdf and see what it is associated with, if anything?

/rcw

Re: Swap1 volume?

Leam Hall — Tue, 08 Feb 2011 12:18:44 GMT

lvol09 is not used, nor is ecc far as I can tell. Whomever built this beast set up, literally dozens of volumes each in their own VG. I'm trying to undo that. I don't mind allocating the swap space, but I don't want unnecessary VGs. It makes volume manipulation difficult.

Re: Swap1 volume?

Jose Mosquera — Tue, 08 Feb 2011 12:23:25 GMT

Hi,

Before you remove swap space please remember the relationship between physical memory installed and swap memory that you must provide for system tuning .

Take a look of this document:
http://h21007.www2.hp.com/portal/download/files/unprot/devresource/docs/techpapers/uxperfcookbook.pdf

Rgds.

Re: Swap1 volume?

Rita C Workman — Tue, 08 Feb 2011 12:32:29 GMT

As long as you can confirm that those other references are absolutely connected to nothing, you should be okay to remove them.

But remember, just because you don't see a file system mounted, does not mean a disk is not in use. Be sure what you plan to remove is not being used as a 'raw device' first!

Regards,
Rita

Re: Swap1 volume?

Leam Hall — Tue, 08 Feb 2011 12:39:25 GMT

Rita,

How do I check for raw volume usage? This is already part of a volume group, can it also be a raw device?

Thanks!

Leam

Re: Swap1 volume?

Rita C Workman — Tue, 27 Sep 2011 23:38:29 GMT

Take a look at Matt Kurkela's response on this thread...it's pretty helpful.

http://h30499.www3.hp.com/t5/System-Administration/how-to-find-unused-disk-devices-in-hpunix/m-p/4208755#M325847

Regards,
Rita