[ale] ext3

[Chris Ricker]

On Tue, 18 Sep 2001, Stuffed Crust wrote:

> On Tue, Sep 18, 2001 at 07:00:00PM -0700, Stephen Turner wrote:
> > the ext3 or jurnaling file system.. its faster?
> > better? i have not heard of it, is it worth while?
> 
> A journalling filesystem is by definition slower than a non-journalling
> filesystem, because the same data is written multiple times.  (first to
> the journal, then to the actual filesystem)

Actually, that's the common perception, but it also happens to be wrong.  
If you benchmark ext2 and ext3, for example, you'll find that 3 gives higher
throughput than 2 under almost all real or contrived loads.

The reason is that, while it's true that journals end up writing metadata
twice (almost no jfs actually journals the files themselves), they also end
up coalescing the writes, minimizing head motion on the drives....

later,
chris


--
To unsubscribe: mail majordomo at ale.org with "unsubscribe ale" in message body.