From: Jeff King <peff@peff.net>
Date: Sat, 01 Mar 2008 08:18:33 GMT
Subject: Re: [RFC/PATCH] rename: warn user when we have turned off rename detection
Message-ID: <20080301081832.GB31855@coredump.intra.peff.net>
In-Reply-To: <7vtzjq6gnv.fsf@gitster.siamese.dyndns.org>

On Fri, Feb 29, 2008 at 11:35:00PM -0800, Junio C Hamano wrote:

> > +	if ((num_create > rename_limit && num_src > rename_limit) ||
> > +	    (num_create * num_src > rename_limit * rename_limit)) {
> > +		warning("too many files, skipping inexact rename detection");
> >  		goto cleanup;
> > +	}
> > 
> >  	mx = xmalloc(sizeof(*mx) * num_create * num_src);
> >  	for (dst_cnt = i = 0; i < rename_dst_nr; i++) {
> 
> This reminds me of the 6d24ad9 (Optimize rename detection for a huge diff)
> topic that reduces the above allocation greatly.  Some benching with the
> patch may prove useful to establish much higher limits, I suspect.

Actually, my timings are about the same. While the patch you mentioned
is nice for reducing the memory consumption, we still have an O(n^2)
loop.

-Peff