Implement get_expired stats

7 files changed, 46 insertions, 24 deletions

diff --git a/doc/protocol.txt b/doc/protocol.txt
index 7e72508..eaa3b16 100644
--- a/doc/protocol.txt
+++ b/doc/protocol.txt
@@ -542,6 +542,8 @@ integers separated by a colon (treat this as a floating point number).
 |                       |         | and found present                         |
 | get_misses            | 64u     | Number of items that have been requested  |
 |                       |         | and not found                             |
+| get_expired           | 64u     | Number of items that have been requested  |
+|                       |         | but had already expired.                  |
 | delete_misses         | 64u     | Number of deletions reqs for missing keys |
 | delete_hits           | 64u     | Number of deletion reqs resulting in      |
 |                       |         | an item being removed.                    |
diff --git a/items.c b/items.c
index 93c83ba..938d578 100644
--- a/items.c
+++ b/items.c
@@ -659,7 +659,7 @@ void item_stats_sizes(ADD_STAT add_stats, void *c) {
 }
 
 /** wrapper around assoc_find which does the lazy expiration logic */
-item *do_item_get(const char *key, const size_t nkey, const uint32_t hv) {
+item *do_item_get(const char *key, const size_t nkey, const uint32_t hv, conn *c) {
     item *it = assoc_find(key, nkey, hv);
     if (it != NULL) {
         refcount_incr(&it->refcount);
@@ -711,6 +711,9 @@ item *do_item_get(const char *key, const size_t nkey, const uint32_t hv) {
             do_item_unlink(it, hv);
             do_item_remove(it);
             it = NULL;
+            pthread_mutex_lock(&c->thread->stats.mutex);
+            c->thread->stats.get_expired++;
+            pthread_mutex_unlock(&c->thread->stats.mutex);
             if (was_found) {
                 fprintf(stderr, " -nuked by expire");
             }
@@ -727,8 +730,8 @@ item *do_item_get(const char *key, const size_t nkey, const uint32_t hv) {
 }
 
 item *do_item_touch(const char *key, size_t nkey, uint32_t exptime,
-                    const uint32_t hv) {
-    item *it = do_item_get(key, nkey, hv);
+                    const uint32_t hv, conn *c) {
+    item *it = do_item_get(key, nkey, hv, c);
     if (it != NULL) {
         it->exptime = exptime;
     }
diff --git a/items.h b/items.h
index 4e492b4..8add1ef 100644
--- a/items.h
+++ b/items.h
@@ -23,8 +23,8 @@ void item_stats_totals(ADD_STAT add_stats, void *c);
 /*@null@*/
 void item_stats_sizes(ADD_STAT add_stats, void *c);
 
-item *do_item_get(const char *key, const size_t nkey, const uint32_t hv);
-item *do_item_touch(const char *key, const size_t nkey, uint32_t exptime, const uint32_t hv);
+item *do_item_get(const char *key, const size_t nkey, const uint32_t hv, conn *c);
+item *do_item_touch(const char *key, const size_t nkey, uint32_t exptime, const uint32_t hv, conn *c);
 void item_stats_reset(void);
 extern pthread_mutex_t lru_locks[POWER_LARGEST];
 
diff --git a/memcached.c b/memcached.c
index 07f8ab5..eb5ffd3 100644
--- a/memcached.c
+++ b/memcached.c
@@ -179,6 +179,7 @@ static rel_time_t realtime(const time_t exptime) {
 static void stats_init(void) {
     stats.curr_items = stats.total_items = stats.curr_conns = stats.total_conns = stats.conn_structs = 0;
     stats.get_cmds = stats.set_cmds = stats.get_hits = stats.get_misses = stats.evictions = stats.reclaimed = 0;
+    stats.get_expired = 0;
     stats.touch_cmds = stats.touch_misses = stats.touch_hits = stats.rejected_conns = 0;
     stats.malloc_fails = 0;
     stats.curr_bytes = stats.listen_disabled_num = 0;
@@ -1296,9 +1297,9 @@ static void process_bin_get_or_touch(conn *c) {
         protocol_binary_request_touch *t = binary_get_request(c);
         time_t exptime = ntohl(t->message.body.expiration);
 
-        it = item_touch(key, nkey, realtime(exptime));
+        it = item_touch(key, nkey, realtime(exptime), c);
     } else {
-        it = item_get(key, nkey);
+        it = item_get(key, nkey, c);
     }
 
     if (it) {
@@ -2057,7 +2058,7 @@ static void process_bin_update(conn *c) {
         /* Avoid stale data persisting in cache because we failed alloc.
          * Unacceptable for SET. Anywhere else too? */
         if (c->cmd == PROTOCOL_BINARY_CMD_SET) {
-            it = item_get(key, nkey);
+            it = item_get(key, nkey, c);
             if (it) {
                 item_unlink(it);
                 item_remove(it);
@@ -2207,7 +2208,7 @@ static void process_bin_delete(conn *c) {
         stats_prefix_record_delete(key, nkey);
     }
 
-    it = item_get(key, nkey);
+    it = item_get(key, nkey, c);
     if (it) {
         uint64_t cas = ntohll(req->message.header.request.cas);
         if (cas == 0 || cas == ITEM_get_cas(it)) {
@@ -2308,7 +2309,7 @@ static void complete_nread(conn *c) {
  */
 enum store_item_type do_store_item(item *it, int comm, conn *c, const uint32_t hv) {
     char *key = ITEM_key(it);
-    item *old_it = do_item_get(key, it->nkey, hv);
+    item *old_it = do_item_get(key, it->nkey, hv, c);
     enum store_item_type stored = NOT_STORED;
 
     item *new_it = NULL;
@@ -2611,6 +2612,7 @@ static void server_stats(ADD_STAT add_stats, conn *c) {
     APPEND_STAT("cmd_touch", "%llu", (unsigned long long)thread_stats.touch_cmds);
     APPEND_STAT("get_hits", "%llu", (unsigned long long)slab_stats.get_hits);
     APPEND_STAT("get_misses", "%llu", (unsigned long long)thread_stats.get_misses);
+    APPEND_STAT("get_expired", "%llu", (unsigned long long)thread_stats.get_expired);
     APPEND_STAT("delete_misses", "%llu", (unsigned long long)thread_stats.delete_misses);
     APPEND_STAT("delete_hits", "%llu", (unsigned long long)slab_stats.delete_hits);
     APPEND_STAT("incr_misses", "%llu", (unsigned long long)thread_stats.incr_misses);
@@ -2907,7 +2909,7 @@ static inline void process_get_command(conn *c, token_t *tokens, size_t ntokens,
                 return;
             }
 
-            it = item_get(key, nkey);
+            it = item_get(key, nkey, c);
             if (settings.detail_enabled) {
                 stats_prefix_record_get(key, nkey, NULL != it);
             }
@@ -3129,7 +3131,7 @@ static void process_update_command(conn *c, token_t *tokens, const size_t ntoken
         /* Avoid stale data persisting in cache because we failed alloc.
          * Unacceptable for SET. Anywhere else too? */
         if (comm == NREAD_SET) {
-            it = item_get(key, nkey);
+            it = item_get(key, nkey, c);
             if (it) {
                 item_unlink(it);
                 item_remove(it);
@@ -3170,7 +3172,7 @@ static void process_touch_command(conn *c, token_t *tokens, const size_t ntokens
         return;
     }
 
-    it = item_touch(key, nkey, realtime(exptime_int));
+    it = item_touch(key, nkey, realtime(exptime_int), c);
     if (it) {
         item_update(it);
         pthread_mutex_lock(&c->thread->stats.mutex);
@@ -3259,7 +3261,7 @@ enum delta_result_type do_add_delta(conn *c, const char *key, const size_t nkey,
     int res;
     item *it;
 
-    it = do_item_get(key, nkey, hv);
+    it = do_item_get(key, nkey, hv, c);
     if (!it) {
         return DELTA_ITEM_NOT_FOUND;
     }
@@ -3378,7 +3380,7 @@ static void process_delete_command(conn *c, token_t *tokens, const size_t ntoken
         stats_prefix_record_delete(key, nkey);
     }
 
-    it = item_get(key, nkey);
+    it = item_get(key, nkey, c);
     if (it) {
         MEMCACHED_COMMAND_DELETE(c->sfd, ITEM_key(it), it->nkey);
 
diff --git a/memcached.h b/memcached.h
index df972f5..e53e642 100644
--- a/memcached.h
+++ b/memcached.h
@@ -238,6 +238,7 @@ struct thread_stats {
     pthread_mutex_t   mutex;
     uint64_t          get_cmds;
     uint64_t          get_misses;
+    uint64_t          get_expired;
     uint64_t          touch_cmds;
     uint64_t          touch_misses;
     uint64_t          delete_misses;
@@ -272,6 +273,7 @@ struct stats {
     uint64_t      touch_cmds;
     uint64_t      get_hits;
     uint64_t      get_misses;
+    uint64_t      get_expired;
     uint64_t      touch_hits;
     uint64_t      touch_misses;
     uint64_t      evictions;
@@ -583,8 +585,8 @@ conn *conn_from_freelist(void);
 bool  conn_add_to_freelist(conn *c);
 int   is_listen_thread(void);
 item *item_alloc(char *key, size_t nkey, int flags, rel_time_t exptime, int nbytes);
-item *item_get(const char *key, const size_t nkey);
-item *item_touch(const char *key, const size_t nkey, uint32_t exptime);
+item *item_get(const char *key, const size_t nkey, conn *c);
+item *item_touch(const char *key, const size_t nkey, uint32_t exptime, conn *c);
 int   item_link(item *it);
 void  item_remove(item *it);
 int   item_replace(item *it, item *new_it, const uint32_t hv);
diff --git a/t/stats.t b/t/stats.t
index 91df4d6..6234c49 100755
--- a/t/stats.t
+++ b/t/stats.t
@@ -1,7 +1,7 @@
 #!/usr/bin/perl
 
 use strict;
-use Test::More tests => 98;
+use Test::More tests => 103;
 use FindBin qw($Bin);
 use lib "$Bin/lib";
 use MemcachedTest;
@@ -30,6 +30,7 @@ my $sock = $server->sock;
 ## STAT cmd_touch 0
 ## STAT get_hits 0
 ## STAT get_misses 0
+## STAT get_expired 0
 ## STAT delete_misses 0
 ## STAT delete_hits 0
 ## STAT incr_misses 0
@@ -71,10 +72,10 @@ my $sock = $server->sock;
 my $stats = mem_stats($sock);
 
 # Test number of keys
-is(scalar(keys(%$stats)), 53, "53 stats values");
+is(scalar(keys(%$stats)), 54, "54 stats values");
 
 # Test initial state
-foreach my $key (qw(curr_items total_items bytes cmd_get cmd_set get_hits evictions get_misses
+foreach my $key (qw(curr_items total_items bytes cmd_get cmd_set get_hits evictions get_misses get_expired
                  bytes_written delete_hits delete_misses incr_hits incr_misses decr_hits
                  decr_misses listen_disabled_num lrutail_reflocked time_in_listen_disabled_us)) {
     is($stats->{$key}, 0, "initial $key is zero");
@@ -190,6 +191,7 @@ is(0, $stats->{'cmd_get'});
 is(0, $stats->{'cmd_set'});
 is(0, $stats->{'get_hits'});
 is(0, $stats->{'get_misses'});
+is(0, $stats->{'get_expired'});
 is(0, $stats->{'delete_misses'});
 is(0, $stats->{'delete_hits'});
 is(0, $stats->{'incr_misses'});
@@ -203,6 +205,15 @@ is(0, $stats->{'evictions'});
 is(0, $stats->{'reclaimed'});
 is(0, $stats->{'lrutail_reflocked'});
 
+# item expired
+print $sock "set should_expire 0 1 6\r\nfooval\r\n";
+is(scalar <$sock>, "STORED\r\n", "set item to expire");
+sleep(2);
+print $sock "get should_expire\r\n";
+is(scalar <$sock>, "END\r\n", "item not returned");
+my $stats = mem_stats($sock);
+is(1, $stats->{'get_expired'}, "get_expired counter is 1");
+
 print $sock "flush_all\r\n";
 is(scalar <$sock>, "OK\r\n", "flushed");
 
diff --git a/thread.c b/thread.c
index 7c56445..0a1a859 100644
--- a/thread.c
+++ b/thread.c
@@ -486,22 +486,22 @@ item *item_alloc(char *key, size_t nkey, int flags, rel_time_t exptime, int nbyt
  * Returns an item if it hasn't been marked as expired,
  * lazy-expiring as needed.
  */
-item *item_get(const char *key, const size_t nkey) {
+item *item_get(const char *key, const size_t nkey, conn *c) {
     item *it;
     uint32_t hv;
     hv = hash(key, nkey);
     item_lock(hv);
-    it = do_item_get(key, nkey, hv);
+    it = do_item_get(key, nkey, hv, c);
     item_unlock(hv);
     return it;
 }
 
-item *item_touch(const char *key, size_t nkey, uint32_t exptime) {
+item *item_touch(const char *key, size_t nkey, uint32_t exptime, conn *c) {
     item *it;
     uint32_t hv;
     hv = hash(key, nkey);
     item_lock(hv);
-    it = do_item_touch(key, nkey, exptime, hv);
+    it = do_item_touch(key, nkey, exptime, hv, c);
     item_unlock(hv);
     return it;
 }
@@ -613,6 +613,7 @@ void threadlocal_stats_reset(void) {
 
         threads[ii].stats.get_cmds = 0;
         threads[ii].stats.get_misses = 0;
+        threads[ii].stats.get_expired = 0;
         threads[ii].stats.touch_cmds = 0;
         threads[ii].stats.touch_misses = 0;
         threads[ii].stats.delete_misses = 0;
@@ -653,6 +654,7 @@ void threadlocal_stats_aggregate(struct thread_stats *stats) {
 
         stats->get_cmds += threads[ii].stats.get_cmds;
         stats->get_misses += threads[ii].stats.get_misses;
+        stats->get_expired += threads[ii].stats.get_expired;
         stats->touch_cmds += threads[ii].stats.touch_cmds;
         stats->touch_misses += threads[ii].stats.touch_misses;
         stats->delete_misses += threads[ii].stats.delete_misses;