Re: /usr/lib vs /usr/libexec
On Wednesday 11 May 2005 17:35, Humberto Massa wrote:
> This is not an imaginary problem, after all, in principle.
>
> Let's see, as I wrote before, my installation has *thousands* of files
> in /usr/lib and, in some filesystems, this can add up to a very large
> time (and ab-use of dentry cache memory) to link, say, Konqueror (which
> links to *hundreds* of shared objects).
>
> Imagine that, to load Konqui, you have to go 200 times to the disk (ok,
> cache, but...), each of them reading the 10000 entries I have in
> /usr/lib, some of them twice or three times, to follow the symlinks.
>
> This is a real inefficiency.
That is a possibility, it does sound sub-optimal. However, if you optimise
before measuring there is no guarantee things will get any faster.
Is reading the directory taking an appreciable amount of time compared to say,
doing relocations?
> So, if you ask me for MHO, ext3 should be used by default *with*
> directory indexing. And maybe FHS should be pressed to provide something
> like /usr/libexec.
How much stuff would go in libexec? I suspect it would mostly be stuff in
currently in subdirectories of /usr/lib, which is less than 7% of
my /usr/lib. So 7% performance improvement on something that is yet to be
proven to be a bottleneck. On some filesystems. Without benchmarks it's a
pointless discussion anyway.
Reply to: