Benefits of using an external journal?

Gullible Jones · 2008-01-12 00:30:34

I've noticed that all the journaled filesystems allow you to specify a storage device or partition as an external journal. Is there any advantage to doing this, e.g. creating a journal partition for your filesystems? Could having a separate partition for metadata journaling improve performance, or would it just present an additional hazard in the event of a hard drive failure?

byte · 2008-01-12 01:26:32

I'd consider it first and foremost a (serious) performance improvement.

theringmaster · 2008-01-12 02:41:20

http://wiki.archlinux.org/index.php/JFS … al_Journal

Here's a small right up (jfs oriented at least)

Gullible Jones · 2008-01-12 17:08:01

ArchWiki wrote:

Obviously, an external journal is only effective if the journal and its file system exists on separate physical devices.

That's the problem, I don't know if there's any benefit to having a separate journal partition on the same device, which all the other partitions use. Would localizing journal writes to one partition improve performance, or just create a single-point-of-failure hazard?

byte · 2008-01-12 20:49:47

Each filesystem needs its own dedicated journal, you can't handle it like a shared swap partition.

Arch Linux

#1 2008-01-12 00:30:34

Benefits of using an external journal?

#2 2008-01-12 01:26:32

Re: Benefits of using an external journal?

#3 2008-01-12 02:41:20

Re: Benefits of using an external journal?

#4 2008-01-12 17:08:01

Re: Benefits of using an external journal?

#5 2008-01-12 20:49:47

Re: Benefits of using an external journal?

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