Originally posted by: SystemAdmin

What is the potential problem with all filesystems on the AIX 5.3L box in jfs2 type?

Originally posted by: SystemAdmin

Function JFS JFS2
Architectural maximum file system size 1 TB 4 PB
Architectural maximum file size 64 GB 4 PB
Number of i-nodes Fixed Dynamic
Inode size 128 bytes 512 bytes
Fragment size 512 512
Block size 4096 4096
Directory organization Linear B-tree
Compression Yes No
Default ownership at creation sys.sys root.system
SGID of default file mode SGID=on SGID=off
Quotas Yes Yes
---------------JFS2 filesystem not supports Compression--------------

Originally posted by: SystemAdmin

I knew the difference. But I am asking if I configure all my filesystem with jfs2 file type, what kind of the problem will I face comparing to all jfs type or some of the filesystems? in my case, my box is p550, 2 CPU, lcpu=4, 4 G memory, OS 5.3L, 64 bits. The reason I asked because the IBM contractor installed and configured all user filesystems in jfs, but all OS related in jfs2.

Originally posted by: MarkTaylor

I am not really sure I understand the question ? you are asking
i) what are the pitfalls of jfs2 ? jfs2 on the whole is more managable, scalable and faster than jfs. jfs2 is optimised for 64 bit, but will still run faster than jfs on a 32 bit kernel due to design (btree). jfs2 still has some defects that will not be fixed until AIX 5.4 .. use google, there are many threads.

Or

ii) what are the benefits of jfs2 over jfs .. jfs has some pretty nasty limitations and is very antiquated and slow by design.

What kernel are you running ? 32 or 64 bit ?

HTH
Mark Taylor

Originally posted by: SystemAdmin

My kernel is 64 bit based on the prtconf shown. So i better have all my filesystems in jfs2 type? what happen to my current filesytems already in jfs type? do I have to alter them into jfs2? is that an easy task?

Originally posted by: orphy

Are you having any issues with your current JFS filesystems now? If not, there
is really no reason to change them all to JFS2. However, if you hit some JFS
limits (e.g. you are not able to reduce FS size, or not able to create 2gb+
files), you should consider changing them to JFS2. As far as I know, there is no
easy way to covert from JFS to JFS2. You'll have to create the JFS2, move the
files from JFS over, and then nuke the JFS. You can always do backup/restore if
you have disk space issue.

Also, AIX has no problem with both JFS and JFS2 living in the same VG. The only
thing is that it will cause you an extra PP unless of course you use INLINE log.
Orphy