Re: speed up test-stat-time

[Jim Meyering]

Eric Blake wrote:
> Multiple calls to sleep(2) add up fast!  I've especially noticed it while
> working on my utimensat series, where repeatedly running 'make check' stalls 
> on
> this test.  Unless you are insane enough to run on FAT, or unlucky enough to 
> be
> on mingw (since I didn't want to drag in a dependency on xnanosleep just for
> this test), this patch gives an order-of-magnitude speedup to test-stat-time.
>
>
> From: Eric Blake <address@hidden>
> Date: Fri, 9 Oct 2009 11:55:46 -0600
> Subject: [PATCH] test-stat-time: speed up execution
>
> Eight seconds was painfully long.
>
> * tests/test-stat-time.c (test_ctime) [!W32]: Avoid compiler
> warning on mingw.
> (nap): New helper function.
> (prepare_test): Use it to reduce sleep time.
> (test_mtime, test_ctime, test_birthtime): Allow for subsecond
> execution.
> * modules/stat-time-tests (configure.ac): Check for usleep.
...
> +#if !HAVE_USLEEP
> +  /* Assume the worst case file system of FAT, which has a granularity
> +     of 2 seconds.  */
> +  sleep (2);
> +#else /* HAVE_USLEEP */

Nice.

However, I saw no improvement when running that test via coreutils.
I guess your environment already had a test for the usleep function.

>From fd35e151ef9bb99c504462691dd33f41254a2b32 Mon Sep 17 00:00:00 2001
From: Jim Meyering <address@hidden>
Date: Sat, 10 Oct 2009 11:05:22 +0200
Subject: [PATCH] stat-time-tests: check for the usleep function

* modules/stat-time-tests (configure.ac): Now that we test HAVE_USLEEP.
---
 ChangeLog               |    5 +++++
 modules/stat-time-tests |    1 +
 2 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index c0a779a..9b05c4e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2009-10-10  Jim Meyering  <address@hidden>
+
+       stat-time-tests: check for the usleep function
+       * modules/stat-time-tests (configure.ac): Now that we test HAVE_USLEEP.
+
 2009-10-10  Bruno Haible  <address@hidden>

        * modules/xnanosleep: Put the Link section after the Include section.
diff --git a/modules/stat-time-tests b/modules/stat-time-tests
index d4f6041..3913ad2 100644
--- a/modules/stat-time-tests
+++ b/modules/stat-time-tests
@@ -6,6 +6,7 @@ time
 sleep

 configure.ac:
+AC_CHECK_FUNCS([usleep])

 Makefile.am:
 TESTS += test-stat-time
--
1.6.5.rc3.227.g2ff1c