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bdf output doubt

 
boomerang
Frequent Advisor

bdf output doubt

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
8 REPLIES 8
Pete Randall
Outstanding Contributor

Re: bdf output doubt

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

Pete
Ismail Azad
Esteemed Contributor

Re: bdf output doubt

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
Read, read and read... Then read again until you read "between the lines".....
Pete Randall
Outstanding Contributor

Re: bdf output doubt

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

Pete
Ismail Azad
Esteemed Contributor

Re: bdf output doubt

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
Read, read and read... Then read again until you read "between the lines".....
Alzhy
Honored Contributor

Re: bdf output doubt

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

can you post:

fstyp -v /dev/vg03/rlvol20

Hakuna Matata.
boomerang
Frequent Advisor

Re: bdf output doubt

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
DeafFrog
Valued Contributor

Re: bdf output doubt

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,
FrogIsDeaf
Manix
Honored Contributor

Re: bdf output doubt

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