Re: JFS on HPUX?

Yes, i find JFS (e.g. VxFS) is preferable to HFS on HP-UX 11.0.

Due to the nature of the journaled file system, an fsck (file system check) will run much, much faster on a JFS volumne than on an HFS (or UFS) volume. This can significantly speed up the boot time after a system panic.

As Jonathon points out, putting your Oracle data files on a JFS volume does not put your data at risk. Beware, there are some options that can be specified for a VxFS mount that can (apparently) marginally increase performance and significantly increase the risk of data loss for other applications.

BTW.. i use VxFS (on HP-UX 11) for the archived redo logs and as a destination for my hot backups. All of my online data files are in "raw" partitions (created with logical volume manager). The biggest drawback anyone has been able to point out to me with "raw" partitions is inflexibility and the large number of unix commands that cannot be used on "raw" partitions, but I haven't actually encountered problems with either. LVM allows me to resize partitions (i.e. add extents), and since i reference the logical volumes through symbolic links, it is relatively straightforward to relocate data files.

HP and Oracle both recommend (in their documentation, anyway) using "raw" partitions and the async i/o driver. The representatives from Veritas, on the other hand, are (understandably) recommending "Storage Edition for Oracle" for HP-UX.

"Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> wrote in message news:956253821.25899.0.nnrp-12.9e984b29_at_news.demon.co.uk...
>
> The nature of Oracle writes is such that
> you do not lose 'pending writes'. A database
> change is committed only if the redo log
> write has actually been confirmed by the
> O/S as a real write. (Obviously various
> hardware devices such as battery backed cache
> on disks may lie and claim that data is on disc
> when it is not).
>
> The risk of data loss due to pending writes
> is therefore no different on JFS/HFS than it
> is on raw.
>
> JFS is actually faster in most cases than
> HFS - particularly for writing the archived
> redo logs. It is quite a good idea to stick
> to raw for the online redo log, (if you have a
> very high throughput system) but if you go to
> JFS, make sure you install the advanced JFS
> option that allows you to enable direct i/o,
> otherwise you may find that the redo has to
> run a read/write cycle to write the redo log
> in multiples of 4K.
>
> --
>
> Jonathan Lewis
> Yet another Oracle-related web site:

 http://www.jlcomp.demon.co.uk
>
> Kevin Brand wrote in message <8dneag$pg3$1_at_news.gte.com>...
> >
> >I'm trying to decide whether to use Journaled or
 non-Journaled filesystems
> >on HPUX for the Oracle RDBMS datafiles.
> >
> >Most all of my previous Oracle builds have used raw device
 files, so using
> >the filesystem for datafiles is unfamiliar territory.
> >
> >My concern is that a power failure or other system crash
 would cause
 pending
> >writes to be lost if I use HFS as opposed to JFS for both the
 datafiles and
> >the redo logs, which would not be a good thing. On the other
 hand, using
> >JFS could limit write performance.
> >
> >Are these assumptions correct and what is the general feel of
 those of you
> >versed in using Oracle on HP?
> >
> >Thanks,
> >
> >-Kevin
> >
> >
>
>
>
Received on Sat Apr 22 2000 - 00:00:00 CDT