added madvise MADV_RANDOM is rrd_update uses mmap

git-svn-id: svn://svn.oetiker.ch/rrdtool/branches/1.2/program@1066 a5681a0c-68f1-0310-ab6d-d61299d08faa

diff --git a/configure.ac b/configure.ac
index 202f370..df21955 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -248,7 +248,7 @@ AC_C_BIGENDIAN
 dnl for each function found we get a definition in config.h 
 dnl of the form HAVE_FUNCTION
 
-AC_CHECK_FUNCS(tzset mbstowcs opendir readdir chdir chroot getuid setlocale strerror strerror_r snprintf vsnprintf fpclass class fp_class isnan memmove strchr mktime getrusage gettimeofday posix_fadvise)
+AC_CHECK_FUNCS(tzset mbstowcs opendir readdir chdir chroot getuid setlocale strerror strerror_r snprintf vsnprintf fpclass class fp_class isnan memmove strchr mktime getrusage gettimeofday posix_fadvise madvise)
 
 
 if test "x$enable_mmap" = xyes; then

diff --git a/src/rrd_update.c b/src/rrd_update.c
index 5f27c2f..608c314 100644 (file)
--- a/src/rrd_update.c
+++ b/src/rrd_update.c
@@ -427,7 +427,12 @@ _rrd_update(const char *filename, const char *tmplt, int argc, const char **argv
         fclose(rrd_file);
        return(-1);
     }
+#ifdef HAVE_MADVISE
+    /* when we use mmaping we tell the kernel the mmap equivalent
+       of POSIX_FADV_RANDOM */
+    madvise(rrd_mmaped_file,rrd_filesize,MADV_RANDOM);
 #endif
+#endif    
     /* loop through the arguments. */
     for(arg_i=0; arg_i<argc;arg_i++) {
        char *stepper = strdup(argv[arg_i]);