[darcs-users] Possibly a very simplistic solution

[Ketil Malde]

David Roundy <droundy at abridgegame.org> writes:

> we'd be able to avoid system calls to a large extent.  On big repos, the
> bottleneck is often stat(2) calls to find modification times and file
> sizes.

I tried on a very small repo, just three files and one subdir.  A
'whatsnew' (with a couple of changes) does:

56 stat64
38 fstat64
29 mmap
~24 each of read, open, write, close

I don't know how this scales, but couldn't the results be cached in
some of these cases?

Each source files seems to be stat64'ed four times, and their copy in
"current" six times, for instance.

(Okay, so I haven't looked at the code, just the strace output.  I
guess there are good reasons.)

-kzm
-- 
If I haven't seen further, it is by standing in the footprints of giants