Re: linux-2.4.10-pre5

[Daniel Phillips]

On September 11, 2001 05:48 pm, Linus Torvalds wrote:
> I actually think that the "start read-ahead for inode blocks when you do
> readdir" might be a bigger win, because that would be a _new_ kind of
> read-ahead that we haven't done before, and might improve performance for
> things like "ls -l" in the cold-cache situation..
> 
> (Although again, because the inode is relatively small to the IO cache
> size, it's probably fairly _hard_ to get a fully cold-cache inode case. So
> I'm not sure even that kind of read-ahead would actually make any
> difference at all).

Having it all in cache makes a huge difference.  For:

  ls -R linux >/dev/null

it's about 5 seconds cold, about .1 second the second time.  A factor of 50!

--
Daniel