Re: git-diff-tree inordinately (O(M*N)) slow on files with many changes
On Mon, 16 Oct 2006, Jim Meyering wrote:
Show 12 quoted lines
> Linus Torvalds <torvalds@osdl.org> wrote:
> > On Mon, 16 Oct 2006, Linus Torvalds wrote:
> ...
> > So I think xdiff has chosen too small a hash. Can you try what happens if
> > you change xdl_hashbits() (in xdiff/xutil.c) instead? Try making it return
> > a bigger value (for example, by initializing "bits" to 2 instead of 0),
> > and see if that makes a difference.
>
> It makes no difference.
>
> Bear in mind that there are a *lot* of duplicate lines in the files
> being compared: filtering each through "sort -u" removes 40-50k lines.
Ok, try to bring down XDL_MAX_EQLIMIT to something like 8 or 16 ...
- Davide