Chris Mason wrote:
On Fri, 2004-04-09 at 01:53, Hans Reiser wrote:
Burnes, James wrote:
I thought nearly all filesystems designed since Berkeley FFS were nearly
immune to fragmentation problems.
After reading the following analysis at Harvard, it seems that
fragmentation is still a problem.
http://www.eecs.harvard.edu/~keith/research/tr94.html
Yeah, I wish I had read this in 94. V3 suffers from the same problems
as FFS does as described in the abstract (all that I read, sorry about
that, I really am a bit busy, so unless someone suggests I should read
more.... ) . V4 cures it though.
I put out some patches last week that try to deal with this in v3.
Describe the algorithmic changes please.
Take
a look through the archives for mail from me.
The v3 patches are an attempt to do better under common workloads. I
think they are a big improvement, and I doubt there's much more that can
(or should) be done beyond simple tweaking.
v4 does a better job, and even if it doesn't, it should at least have
enough info in the metadata such that any problems can be fixed.
-chris
--
Hans
