Re: [PATCH v2] xdiff/xprepare: improve O(n*m) performance in xdl_cleanup_records()

From

Tay Ray Chuan <rctay89@gmail.com>

Date

Aug 17, 2011, 15:55 UTC

Message-ID

<CALUzUxovdmhnRKPaEq01-q0pvez91s_Z_rHWg-FkwcU0VD3HQQ@mail.gmail.com>

In-Reply-To

<20110817052147.GA11253@sigill.intra.peff.net>

On Wed, Aug 17, 2011 at 1:21 PM, Jeff King <peff@peff.net> wrote:

> Wait, what? It was using 0 seconds of user time before, but still taking
> 8.5 seconds? What was it doing? Did you actually warm up your disk cache
> before taking these measurements?

Three runs on the same machine, after a restart.

  $ time git show >/dev/null

  real    0m6.505s
  user    0m0.031s
  sys     0m0.015s

  rctay@TEST-123 /tmp/slono
  $ time git show >/dev/null

  real    0m5.429s
  user    0m0.000s
  sys     0m0.031s

  rctay@TEST-123 /tmp/slono
  $ time git show >/dev/null

  real    0m5.336s
  user    0m0.000s
  sys     0m0.016s

-- 
Cheers,
Ray Chuan