From d278a40cab2bcb6bb0387176d087ce13cd3e843b Mon Sep 17 00:00:00 2001 From: Florian Forster Date: Tue, 18 Aug 2009 21:23:21 +0200 Subject: [PATCH] =?utf8?q?rrdtool=20plugin:=20Optimize=20away=20the=20?= =?utf8?q?=E2=80=98random=5Ftimeout=5Fmod=E2=80=99=20variable.?= MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit --- src/rrdtool.c | 37 ++++++++++++++++++++++++++----------- 1 file changed, 26 insertions(+), 11 deletions(-) diff --git a/src/rrdtool.c b/src/rrdtool.c index 2bcfb6d9..811aea0a 100644 --- a/src/rrdtool.c +++ b/src/rrdtool.c @@ -106,7 +106,6 @@ static rrdcreate_config_t rrdcreate_config = static int cache_timeout = 0; static int cache_flush_timeout = 0; static int random_timeout = 1; -static int random_timeout_mod = 1; static time_t cache_flush_last; static c_avl_tree_t *cache = NULL; static pthread_mutex_t cache_lock = PTHREAD_MUTEX_INITIALIZER; @@ -743,17 +742,29 @@ static int rrd_cache_insert (const char *filename, filename, rc->values_num, (unsigned long)(rc->last_value - rc->first_value)); - if ((rc->last_value - rc->first_value + rc->random_variation) >= cache_timeout) + if ((rc->last_value + rc->random_variation - rc->first_value) >= cache_timeout) { /* XXX: If you need to lock both, cache_lock and queue_lock, at * the same time, ALWAYS lock `cache_lock' first! */ if (rc->flags == FLAG_NONE) { int status; - rc->random_variation = (random_timeout - (rand() % random_timeout_mod)); + status = rrd_queue_enqueue (filename, &queue_head, &queue_tail); if (status == 0) rc->flags = FLAG_QUEUED; + + /* Update the jitter value. Negative values are + * slightly preferred. */ + if (random_timeout > 0) + { + rc->random_variation = (rand () % (2 * random_timeout)) + - random_timeout; + } + else + { + rc->random_variation = 0; + } } else { @@ -994,16 +1005,20 @@ static int rrd_config (const char *key, const char *value) } else if (strcasecmp ("RandomTimeout", key) == 0) { - random_timeout = atoi (value); - if( random_timeout < 0 ) + int tmp; + + tmp = atoi (value); + if (tmp < 0) + { + fprintf (stderr, "rrdtool: `RandomTimeout' must " + "be greater than or equal to zero.\n"); + ERROR ("rrdtool: `RandomTimeout' must " + "be greater then or equal to zero."); + } + else { - fprintf (stderr, "rrdtool: `RandomTimeout' must " - "be greater than or equal to zero.\n"); - ERROR ("rrdtool: `RandomTimeout' must " - "be greater then or equal to zero.\n"); + random_timeout = tmp; } - else if (random_timeout==0) {random_timeout=1;} - else {random_timeout_mod = random_timeout * 2;} } else { -- 2.11.0