VxFS vs HFS

[Michael D. Zorn]

I'm working on getting a new server running - rp3410. HP did the config, so now I'm setting up PVs, LVs and VGs.

Is there much of a difference between VxFS and HFS - as far as looking at it from the outside goes - like the basic pv, lv, vg commands?

I also noticed that the root fs is hfs, and the other is VxFS.

[Patrick Wallek · Accepted solution]

Go with VxFS for EVERYTHING EXCEPT /stand.

VxFS, since it is a journaled filesystem, will fsck much much much quicker in the event the system crashes. VxFS also allows you to do online expansion of LVs (if you have Advance JFS product), reduction of LVs and allows for MUCH larger files and file systems.

It really makes no sense to use HFS for anything besides /stand.

[James R. Ferguson]

Hi:

VxFS is otherwise known as a Journaled File System and is superior in performance to HFS.

VxFS and HFS are *filesystem* types. Filesystems sit inside logical volumes in LVM parlance. Hence, no, the 'pv*', 'lv*' and 'vg*' commands are common.

Up until 11.23, '/stand' must be an HFS filessystem type in order for the loader to find and boot the kernel.

Regards!

...JRF...

[A. Clay Stephenson]

From the perspective LVM the commands are exactly the same; LVM doesn't care if a filesystem is even installed. The differences are in the filesystem commands (newfs,mkfs,fsadm, and mount). Normally, the ONLY hfs filesystem on an HP-UX box these days is /stand because the boot firmware on older boxes doesn't understand vxfs. The performance of vxfs is far superior to that of hfs so unless you have some compelling reason to run hfs everything except /stand should be vxfs.

The other commands that differ between hfs and vxfs are those related to ACL's; the commands are very similar in funnction but different in name.

[Gary L. Paveza, Jr.]

The commands you referrenced are logical volume commands. VxFS and HFS are filesystems. They go on the logical volumes you created. The steps preceeding creating a filesystem (creating volume group, creating logical volumes) are identical whether you use HFS or VxFS as your filesystem.

That being said, use VxFS instead of HFS for your filesystems. VxFS has much greater flexiblity and is much better when it comes to recoverability.

[David Bellamy]

The major difference between HFS and VXFS is that in the case of a system crash vxfs filesystems will come up quicker than HFS file systems. HFS file systems have to be checked and depending on the size of the file system this can take a long time. This doesn't happen with VxFS file systems.

[Bill Hassell]

HFS (or the high performance McKusick filesystem, aka UFS, see http://en.wikipedia.org/wiki/Berkeley_Fast_File_System) was the leader in Unix performance and features a couple of decades ago. It was designed to avoid fragmentation (indeed, there was never a tool to defrag), to have multiple superblocks and would cluster filespace all across the disk. It has a one-time assignment for all inodes when newfs/mkfs first creates the filesystem.

It was much better than PC filesystems which would allocate file space bottom up and best fit. This would leave holes and out of order clusters of data, thus slowing filesystem performance. But one of the downsides is that when the filesystem was not unmounted before a reboot (ie, powerfail or system crash), all the inodes and directory entries had to be checked, essentially a linear task. The more inodes, the longer fsck had to run. To fsck a 5Gb filesystem will require several minute.

So HFS was the standard until 10.00 was released and the Veritas Journaled Filesystem was made available for HP-UX. It had a very rocky start and for almost 2 years, it was to slow and unstable to be used in production. Then about the time 10.20 was released, the majority of showstopper bugs were fixed and VxFS was out-performing HFS. So VxFS is the filesystem of choice fcr HP-UX -- except for /stand.

/stand is special. The HP-UX boot loader requires that the first filesystem following the volume manager area on the boot disk must be HFS. This has been true for all versions of HP-UX until 11.23 where the HP-UX boot loader was drastically revised and now allows VxFS as a filesystem as well as VxVM as a volume manager.

[Sandman!]

Check out this link it might be helpful.

http://www1.itrc.hp.com/service/cki/docDisplay.do?docLocale=en_US&docId=200000080092269

P.S. note that VxFS==JFS

[Michael D. Zorn]

Thanks to all. That's exactly what I needed to know.