On Wed, Mar 13, 2002 at 11:50:32AM -0800, Andrew Morton wrote:
> Now, I think it's fair to say that the ext2/ext3 inter-file fragmentation
> issue is one of the three biggest performance problems in Linux. (The
> other two being excessive latency in the page allocator due to VM writeback
> and read latency in the I/O scheduler).
>
> The fix for interfile fragmentation lies inside ext2/ext3, not inside
> any generic layers of the kernel. And this really is a must-fix,
> because the completion time for writeback is approximately proportional
> to the size of the filesystem. So we're getting, what? Fifty percent
> slower per year?
>
> The `tar xfz linux.tar.gz ; sync' workload can be sped up 4x-5x by
> using find_group_other() for directories. I spent a week or so
> poking at this when it first came up. Basically, *everything*
> which I did to address the rapid-growth problem ended up penalising
> the slow-growth fragmentation - long-term intra-file fragmentation
> suffered at the expense of short-term inter-file fragmentation.
I know ReiserFS has similar problems.
Can anyone say wheather JFS or XFS has this problem also?
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This archive was generated by hypermail 2b29 : Fri Mar 15 2002 - 22:00:15 EST