Defragmentation on vxfs if onlineJFS is not installed

[dragana s-v]

Hi,
Does enyone have sugestion how to do defragmentation on an VxFS if onlineJFS product is not installed?
Also, how to verify what current fragmentation rate is and whether defrag is necessary ?

We are running HP-UX10.20.

Thanks,
Dragana

[James R. Ferguson]

Hi:

The optional ($) Online JFS component adds the ability to do filesystem defragmention (via 'fsadm') along with filesystem size reduction and snapshot backups.

The man pages (1M) for 'fsadm_vxfs' provide a relatively good discussion of fragmentation, although the advanced (or Online) license is necessary to use it.

Regards!

...JRF...

[dragana s-v]

Thanks James for your fast responce. I know what I would have to do if I would have OnlineJFS.But, unfortunately, I don't have it. So, how to handle fragmentation in this case ?

Regards,
Dragana

[Michael Tully · Accepted solution]

Hi,

You are correct, that you cannot de a 'defrag'
if On-Line JFS is not installed.

You basically have two choices in which to
deal with this problem.

1. Create a new logical volume and directory
and copy the information into it. Then unmount
it and remount it on the old directory name.

2. Backup the existing files onto a tape, or
to a spare partition, remove the files from
the existing partition and restore the files.

There is no easy way to tell when a 'defrag'
is required. I would only see this as a
necessity if the filesystem gets regularly
filled with small files.

HTH
~Michael~

[James R. Ferguson]

Hi (again):

As far as I know, you will not be able to discern the extent of fragmentation without the optional component.

If you had an extremely volatile filesystem in which a large number (or percentage) of files were constantly added and removed, you could backup the filesystem; destroy and recreate it; and reload the data from backup. This is extreme, to say the least.

If I had to attempt to measure performance in the absence of the Online component, I'd track the number of blocks allocated to directories in the filesystem (via 'df') and I'd track the time to traverse the filesystem (via 'timex find...'). I'd look for a growth in the number blocks allocated and an increase in search times.

Regards!

...JRF...

[dragana s-v]

Hi Michael and thanks !
Unfortunately this is the answer I was looking for. I knew it will be impossible to do it easy way.

Thanks again, and, here there are your 10 points.

Dragana

[dragana s-v]

You peple are so fast,

Thanks for the reply James.

DSV