From: Jim Meyering Date: Mon, 16 Oct 2006 16:33:23 GMT Subject: Re: git-diff-tree inordinately (O(M*N)) slow on files with many changes Message-ID: <87mz7wp6ek.fsf@rho.meyering.net> In-Reply-To: Linus Torvalds 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.