topic bdf output doubt in Operating System - HP-UX

bdf output doubt

boomerang — Thu, 06 Jan 2011 17:28:16 GMT

Hi Admin,

I have a very basic , simple doubt below is the out of bdf for a particular mount point

Filesystem kbytes used avail %used Mounted on
/dev/vg03/lvol20 76800000 7490192 64978175 10% /flasher

when i subtract (76800000-7490192)= 69309808

but available show in bdf output is 64978175

That means (69309808-64978175)= 4331633

That mean approximately difference of 4 GB .

why is it so ? where is the 4GB why is it not shown by bdf. please suggest

Re: bdf output doubt

Pete Randall — Thu, 06 Jan 2011 17:47:55 GMT

From the bdf man page:

The bdf command does not account for any disk space reserved for swap space . . . . . Non-HFS file systems may have other items not accounted for by this command.

Pete

Re: bdf output doubt

Ismail Azad — Thu, 06 Jan 2011 19:45:58 GMT

Hi,

So adding to Pete , the one big question is , do you have filesystem swap enabled on /flasher?? If so, could be one of the reasons for why is it so?

Regards
Ismail Azad

Re: bdf output doubt

Pete Randall — Thu, 06 Jan 2011 19:56:50 GMT

Another way to look at it is that 4GB out of 70GB is lost to overhead (LVM structures etc.). That's only about 6%.

Pete

Re: bdf output doubt

Ismail Azad — Thu, 06 Jan 2011 20:14:14 GMT

Hi,

> Another way to look at it is that 4GB out of 70GB is lost to overhead (LVM structures etc.). That's only about 6%.

And the overhead is also typical for planning of the LV and not sure if it's just documentation or people actually follow the rule of maintaining a 5% filesystem overhead (some people surprised whenever I say that) space reserved while planning the size of the L.V.

Regards
Ismail Azad

Re: bdf output doubt

Alzhy — Thu, 06 Jan 2011 20:48:44 GMT

I don;t think a 4GB FILESYSTEM overhead for a 70GB filesystem is Normal.

can you post:

fstyp -v /dev/vg03/rlvol20

Re: bdf output doubt

boomerang — Sat, 08 Jan 2011 04:57:14 GMT

Now there is change in utilization

#bdf /flasher
Filesystem kbytes used avail %used Mounted on
/dev/vg03/lvol20 76800000 31653139 42325436 43% /flasher

when i subtract (76800000-31653139)=45146861
but available show in bdf output is 42325436

Now difference is (45146861-42325436)=2821425

#fstyp -v /dev/vg03/rlvol20
vxfs
version: 5
f_bsize: 8192
f_frsize: 1024
f_blocks: 76800000
f_bfree: 45155029
f_bavail: 42332840
f_files: 11385812
f_ffree: 11288756
f_favail: 11288756
f_fsid: 1074069505
f_basetype: vxfs
f_namemax: 254
f_magic: a501fcf5
f_featurebits: 0
f_flag: 16
f_fsindex: 10
f_size: 76800000

No filesystem swap has been enabled on /flasher

I am really confused

Re: bdf output doubt

DeafFrog — Mon, 10 Jan 2011 04:47:15 GMT

Hi ,

can you check if there are some process locking space , fuser -cu /flasher.If this is non production/non-critical can you please umount/mount(fuser -ck /flasher;umount /flasher;mount /flasher) and check the difference.
...just another thought.

Regards,

Re: bdf output doubt

Manix — Mon, 10 Jan 2011 09:52:21 GMT

you may also try lsof | grep -iE 'flasher|lvol20' to see if there are two many
processes touching this file system or freezing space.