"stats reset" should reset eviction counters as well

See: http://code.google.com/p/memcached/issues/detail?id=22

Author: Trond Norbye

assoc.c

@@ -183,7 +183,6 @@ void assoc_delete(const char *key, const size_t nkey) {
 
 static volatile int do_run_maintenance_thread = 1;
 
-extern pthread_mutex_t cache_lock;
 #define DEFAULT_HASH_BULK_MOVE 1
 int hash_bulk_move = DEFAULT_HASH_BULK_MOVE;
 

items.c

@@ -46,6 +46,13 @@ void item_init(void) {
     }
 }
 
+void item_stats_reset(void) {
+    pthread_mutex_lock(&cache_lock);
+    memset(itemstats, 0, sizeof(itemstats_t) * LARGEST_ID);
+    pthread_mutex_unlock(&cache_lock);
+}
+
+
 /* Get the next CAS id for a new item. */
 uint64_t get_cas_id(void) {
     static uint64_t cas_id = 0;

items.h

@@ -27,3 +27,5 @@ void do_item_flush_expired(void);
 
 item *do_item_get(const char *key, const size_t nkey);
 item *do_item_get_nocheck(const char *key, const size_t nkey);
+void item_stats_reset(void);
+extern pthread_mutex_t cache_lock;

memcached.c

@@ -164,6 +164,7 @@ static void stats_reset(void) {
     stats_prefix_clear();
     STATS_UNLOCK();
     threadlocal_stats_reset();
+    item_stats_reset();
 }
 
 static void settings_init(void) {

t/issue_22.t

@@ -0,0 +1,39 @@
+#!/usr/bin/perl
+
+use strict;
+use Test::More tests => 84;
+use FindBin qw($Bin);
+use lib "$Bin/lib";
+use MemcachedTest;
+
+my $server = new_memcached("-m 3");
+my $sock = $server->sock;
+my $value = "B"x66560;
+my $key = 0;
+
+for ($key = 0; $key < 40; $key++) {
+    print $sock "set key$key 0 0 66560\r\n$value\r\n";
+    is (scalar <$sock>, "STORED\r\n", "stored key$key");
+}
+
+my $first_stats  = mem_stats($sock, "items");
+my $first_evicted = $first_stats->{"items:31:evicted"};
+# I get 1 eviction on a 32 bit binary, but 4 on a 64 binary..
+# Just check that I have evictions...
+isnt ($first_evicted, "0", "check evicted");
+
+print $sock "stats reset\r\n";
+is (scalar <$sock>, "RESET\r\n", "Stats reset");
+
+my $second_stats  = mem_stats($sock, "items");
+my $second_evicted = $second_stats->{"items:31:evicted"};
+is ("0", $second_evicted, "check evicted");
+
+for ($key = 40; $key < 80; $key++) {
+    print $sock "set key$key 0 0 66560\r\n$value\r\n";
+    is (scalar <$sock>, "STORED\r\n", "stored key$key");
+}
+
+my $last_stats  = mem_stats($sock, "items");
+my $last_evicted = $last_stats->{"items:31:evicted"};
+is ($last_evicted, "40", "check evicted");