From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jay Soffian <jaysoffian@gmail.com>
Subject: git diff timing oddity
Date: Thu, 6 May 2010 01:04:18 -0400
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git version 1.7.1, Mac OS X 10.6.3, largish repo (42K files, 35K
commits, well packed ~ 1GB). Difference between origin and HEAD is a
single commit.

$ time git diff --stat origin  >/dev/null

real	0m0.942s
user	0m0.713s
sys	0m0.223s

$ time git diff --stat origin  >/dev/null

real	0m0.944s
user	0m0.712s
sys	0m0.227s

$ time git diff --stat origin  >/dev/null

real	0m0.944s
user	0m0.712s
sys	0m0.225s

$ time git diff --stat origin HEAD >/dev/null

real	0m0.022s
user	0m0.006s
sys	0m0.012s

$ time git diff --stat origin HEAD >/dev/null

real	0m0.022s
user	0m0.006s
sys	0m0.013s

$ time git diff --stat origin HEAD >/dev/null

real	0m0.023s
user	0m0.006s
sys	0m0.013s

These should be identical commands, so why is the "origin HEAD" form
running an order of magnitude faster?

j.