topic Re: Strage Disk Usage in Operating System - Tru64 Unix

Strage Disk Usage

admin1979 — Mon, 11 Jan 2010 15:54:17 GMT

Hello,

We have our home directories placed on a cluster nodes running TRU64 5.1A.
Today we noticed a 94% usage for one of the home partitions.

df -k

server1:/home 106645880 91199373 6027352 94% /home

server2:/home1 106645880 94630816 11100304 90% /home1

We immediately started purging/moving large files from /home partition to different locations or delete.
Somehow we supposed to have taken care of around 6 GB.
But surprisingly when we noticed df o/p, it showed same percentage of usage as,

df -k

server1:/home1 106645880 88267614 5998696 94% /home

server1:/home 106645880 94631002 11100120 90% /home1

You can see disk usage for /home is still 94%. Closer look showed that Used bytes have been reduced now (from 91199373 --> 88267614 )
But the available space and %usage does not imply that.

What is happening here can someone plz help?

Thanx,
admin

Re: Strage Disk Usage

Martin Moore — Mon, 11 Jan 2010 19:06:49 GMT

First of all, df can become inaccurate on AdvFS filesystems. If yours is AdvFS, try using /sbin/advfs/vdf or showfdmn and showfsets instead of df.

Second, if you deleted any files that were still open by a running process, the space won't truly be reclaimed until the last process referencing the deleted file exits.

Third, if it's AdvFS, run quotacheck -v against the filesystem (after making sure it's mounted with the userquota and groupquota option -- check fstab). AdvFS uses quotas to keep track of disk space usage, even when the quotas are not enforced. If the quota information gets out of sync, which can happen, the reporting of space usage will also be inaccurate. Running quotacheck -v brings the quota info back into sync.

Martin

Re: Strage Disk Usage

Pieter 't Hart — Tue, 12 Jan 2010 08:37:06 GMT

In adition to the previous remarks
look deeper into your filesystem configuration.
using mount and showfdmn.

If you are using multiple filesets within a single filedomain like
/home is mounted domain1#home
and
/data is mounted domain1#data
both home and data share space of the filedomain.
moving data from home to data will have no effect on used space.

Re: Strage Disk Usage

admin1979 — Thu, 02 Sep 2010 06:28:55 GMT

As mentioned above.