From 528741cb6c7218e7f2f764fa10aa7e67699eadaa Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Sun, 18 May 2008 21:54:43 +0000 Subject: * nscd/cache.c (cache_add): Take additional parameter specifying whether this is in response of a cache refill. Check alignment of package data. Revamp waking of pruning thread. (prune_cache): Small optimization. * nscd/nscd.h: Adjust cache_add prototypes. * nscd/aicache.c: Adjust cache_add calls. * nscd/grpcache.c: Likewise. * nscd/hstcache.c: Likewise. * nscd/initgrcache.c: Likewise. * nscd/pwdcache.c: Likewise. * nscd/servicescache.c: Likewise. * nscd/connections.c (restart): Really disable cache use before exec attempt. If it fails, reenable cache. (nscd_run_prune): Initialize wakeup_time. After wakeup, set wakeup time to max to be able to notice concurrent cache additions. Unlock prune_lock while performing gc. Afterwards compute wakeup time with current wakeup_time value in mind. --- nscd/connections.c | 58 ++++++++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 48 insertions(+), 10 deletions(-) (limited to 'nscd/connections.c') diff --git a/nscd/connections.c b/nscd/connections.c index 15148bdf3d..e6a2c946ae 100644 --- a/nscd/connections.c +++ b/nscd/connections.c @@ -1330,11 +1330,14 @@ cannot change to old working directory: %s; disabling paranoia mode"), } /* Synchronize memory. */ + int32_t certainly[lastdb]; for (int cnt = 0; cnt < lastdb; ++cnt) if (dbs[cnt].enabled) { /* Make sure nobody keeps using the database. */ dbs[cnt].head->timestamp = 0; + certainly[cnt] = dbs[cnt].head->nscd_certainly_running; + dbs[cnt].head->nscd_certainly_running = 0; if (dbs[cnt].persistent) // XXX async OK? @@ -1357,6 +1360,15 @@ cannot change to old working directory: %s; disabling paranoia mode"), dbg_log (_("cannot change current working directory to \"/\": %s"), strerror (errno)); paranoia = 0; + + /* Reenable the databases. */ + time_t now = time (NULL); + for (int cnt = 0; cnt < lastdb; ++cnt) + if (dbs[cnt].enabled) + { + dbs[cnt].head->timestamp = now; + dbs[cnt].head->nscd_certainly_running = certainly[cnt]; + } } @@ -1394,42 +1406,68 @@ nscd_run_prune (void *p) int dont_need_update = setup_thread (&dbs[my_number]); + time_t now = time (NULL); + /* We are running. */ - dbs[my_number].head->timestamp = time (NULL); + dbs[my_number].head->timestamp = now; struct timespec prune_ts; - if (clock_gettime (timeout_clock, &prune_ts) == -1) + if (__builtin_expect (clock_gettime (timeout_clock, &prune_ts) == -1, 0)) /* Should never happen. */ abort (); /* Compute the initial timeout time. Prevent all the timers to go off at the same time by adding a db-based value. */ prune_ts.tv_sec += CACHE_PRUNE_INTERVAL + my_number; + dbs[my_number].wakeup_time = now + CACHE_PRUNE_INTERVAL + my_number; + + pthread_mutex_t *prune_lock = &dbs[my_number].prune_lock; + pthread_cond_t *prune_cond = &dbs[my_number].prune_cond; - pthread_mutex_lock (&dbs[my_number].prune_lock); + pthread_mutex_lock (prune_lock); while (1) { /* Wait, but not forever. */ - int e = pthread_cond_timedwait (&dbs[my_number].prune_cond, - &dbs[my_number].prune_lock, - &prune_ts); - assert (e == 0 || e == ETIMEDOUT); + int e = pthread_cond_timedwait (prune_cond, prune_lock, &prune_ts); + assert (__builtin_expect (e == 0 || e == ETIMEDOUT, 1)); time_t next_wait; - time_t now = time (NULL); + now = time (NULL); if (e == ETIMEDOUT || now >= dbs[my_number].wakeup_time) { + /* We will determine the new timout values based on the + cache content. Should there be concurrent additions to + the cache which are not accounted for in the cache + pruning we want to know about it. Therefore set the + timeout to the maximum. It will be descreased when adding + new entries to the cache, if necessary. */ + if (sizeof (time_t) == sizeof (long int)) + dbs[my_number].wakeup_time = LONG_MAX; + else + dbs[my_number].wakeup_time = INT_MAX; + + pthread_mutex_unlock (prune_lock); + next_wait = prune_cache (&dbs[my_number], now, -1); + next_wait = MAX (next_wait, CACHE_PRUNE_INTERVAL); /* If clients cannot determine for sure whether nscd is running we need to wake up occasionally to update the timestamp. Wait 90% of the update period. */ #define UPDATE_MAPPING_TIMEOUT (MAPPING_TIMEOUT * 9 / 10) if (__builtin_expect (! dont_need_update, 0)) - next_wait = MIN (UPDATE_MAPPING_TIMEOUT, next_wait); + { + next_wait = MIN (UPDATE_MAPPING_TIMEOUT, next_wait); + dbs[my_number].head->timestamp = now; + } + + pthread_mutex_lock (prune_lock); /* Make it known when we will wake up again. */ - dbs[my_number].wakeup_time = now + next_wait; + if (now + next_wait < dbs[my_number].wakeup_time) + dbs[my_number].wakeup_time = now + next_wait; + else + next_wait = dbs[my_number].wakeup_time - now; } else /* The cache was just pruned. Do not do it again now. Just -- cgit v1.2.3