JFS2 File Fragmentation

[dial8d]

Hi All

What is the best way to deal with heavily fragmented files on a jfs2 filesystem ?

I have seen other threads where it has been suggested that removing data from the filesystems, either by copying to temp location, create new filesystems, and then restore.

I was rather hoping that would be un-necessary, and that defragfs might do the trick.

Can anyone confirm ?

Cheers

Alex

 

[cryptoadm]

defragfs

 

[dial8d]

no, defragfs does not defrag fragmented files.

from the LVM redbook.

Running defragfs does not solve the problem of fragmented files. The Defragfs command only reorganizes the free disk blocks so more contiguous free space is available.

 

[khalidaaa]

backup fs-remove fs-create a new fs- restore fs

Regards,
Khalid

 

[dial8d]

Hi Khalid

It just seems like a drastic thing to have to do.

 

[cryptoadm]

Run fileplace to check your fragmentation.

 

[dial8d]

Hi Crypto

Yes, i have already used fileplace, and have confirmed heavily fragmented files.

I was really looking to see if there was a way to resolve this, but without having to go through the pain of backing up, deleting and restoring data into new filesystems.

I just dont understand why defragfs doesnt defrag files. I mean, even windows can do this. Just seems like such a basic requirement. Come on IBM, sort it out !

 

[p5wizard]

Normally with AIX LVM buffering, a fragmented file is no real problem...


HTH,

p5wizard

 

[dial8d]

Its Oracle datafiles with CIO, so these files arent cached.