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authorKevin Ryde <user42@zip.com.au>2000-11-20 21:43:03 +0100
committerKevin Ryde <user42@zip.com.au>2000-11-20 21:43:03 +0100
commit657ba334f30ed26c9b346dfd718f0e0658c103a2 (patch)
treef905f87c005aed6d844d8a421d863e5455735f9e /tune/README
parent07989342fe9932d4f0c0e82708ef89fa4e5b9f2d (diff)
downloadgmp-657ba334f30ed26c9b346dfd718f0e0658c103a2.tar.gz
* tune/Makefile.am (LDFLAGS): Use -all-static.
(speed-dynamic): Dynamic linked version of speed.c. * tune/README: Update.
Diffstat (limited to 'tune/README')
-rw-r--r--tune/README20
1 files changed, 10 insertions, 10 deletions
diff --git a/tune/README b/tune/README
index a7eb34cc7..e4dec1c15 100644
--- a/tune/README
+++ b/tune/README
@@ -114,7 +114,7 @@ generally an idle machine will be necessary to be certain of consistent
results.
The CPU frequency is needed if times in cycles are to be displayed, and it's
-always needed when using a cycle counter time base. time.c knows how to get
+always needed when using a cycle counter time base. freq.c knows how to get
the frequency on some systems, but when that fails, or needs to be
overridden, an environment variable GMP_CPU_FREQUENCY can be used (in
Hertz). For example in "bash" on a 650 MHz machine,
@@ -279,16 +279,16 @@ mpz_add. Don't be surprised if the mallocing is quite slow.
./speed -s 10 -c mpz_init_realloc_clear mpz_add
-The normal libtool compilation of the speed program does a static link to
-libgmp.la and libspeed.la, but will end up dynamic linked to libc.
-Depending on the system, a dynamic linked malloc may be noticeably slower
-than a static one, and there may be value in re-running the libtool link
-command to static link libc for comparison. The example below does a 10
-limb malloc/free or malloc/realloc/free to test the C library. Of course a
-real world program has big problems if it's doing so many mallocs and frees
-that it gets slowed down by a dynamic linked malloc.
+On some systems malloc and free are much slower when dynamic linked. The
+speed-dynamic program can be used to see this. For example the following
+measures malloc/free, first static then dynamic.
+
+ ./speed -s 10 -c malloc_free
+ ./speed-dynamic -s 10 -c malloc_free
+
+Of course a real world program has big problems if it's doing so many
+mallocs and frees that it gets slowed down by a dynamic linked malloc.
- ./speed -s 10 -c malloc_free malloc_realloc_free