Changelog update for 1.2.6 release and Patch originally from the Face…

…book crew, cleaned up and split by dormando.

ChangeLog

@@ -1,3 +1,22 @@
+2008-07-24 [Version 1.2.6-rc1 released]
+
+       * Add support for newer automake (Facebook)
+
+       * DTrace support for Solaris/etc (Trond Norbye)
+
+       * LRU tests (Steve Yen)
+
+       * Handle negative length items properly (Dormando)
+
+       * Don't leave stale data after failed set attempts (Dormando)
+
+       * Fix refcount leaks, which would result in OOM's on all sets
+	       (Dormando)
+
+       * Fix buffer overruns (Dustin Sallings, Tomash Brechko)
+
+       * Fix memory corruption with CAS (Dustin Sallings)
+
 2008-06-11
 
        * Fix -k to work with -d. (reported by Gary Zhu)

memcached.c

@@ -176,7 +176,7 @@ static void settings_init(void) {
     settings.managed = false;
     settings.factor = 1.25;
     settings.chunk_size = 48;         /* space for a modest key and value */
-    settings.num_threads = 4;         /* default number of worker threads */
+    settings.num_threads = 4 + 1;     /* N workers + 1 dispatcher */
     settings.prefix_delimiter = ':';
     settings.detail_enabled = 0;
 }
@@ -3476,7 +3476,7 @@ static int server_socket(const int port, enum protocol prot) {
       if (IS_UDP(prot)) {
         int c;
 
-        for (c = 0; c < settings.num_threads; c++) {
+        for (c = 1; c < settings.num_threads; c++) {
             /* this is guaranteed to hit all threads because we round-robin */
             dispatch_conn_new(sfd, conn_read, EV_READ | EV_PERSIST,
                               UDP_READ_BUFFER_SIZE, ascii_udp_prot);
@@ -3898,7 +3898,7 @@ int main (int argc, char **argv) {
             }
             break;
         case 't':
-            settings.num_threads = atoi(optarg);
+            settings.num_threads = atoi(optarg) + 1; /* Extra dispatch thread */
             if (settings.num_threads == 0) {
                 fprintf(stderr, "Number of threads must be greater than 0\n");
                 return 1;

thread.c

@@ -5,6 +5,7 @@
  *  $Id$
  */
 #include "memcached.h"
+#include <assert.h>
 #include <stdio.h>
 #include <errno.h>
 #include <stdlib.h>
@@ -359,7 +360,7 @@ static void thread_libevent_process(int fd, short which, void *arg) {
 }
 
 /* Which thread we assigned a connection to most recently. */
-static int last_thread = -1;
+static int last_thread = 0;
 
 /*
  * Dispatches a new connection to another thread. This is only ever called
@@ -369,20 +370,24 @@ static int last_thread = -1;
 void dispatch_conn_new(int sfd, enum conn_states init_state, int event_flags,
                        int read_buffer_size, enum protocol prot) {
     CQ_ITEM *item = cqi_new();
-    int thread = (last_thread + 1) % settings.num_threads;
+    int tid = last_thread % (settings.num_threads - 1);
 
-    last_thread = thread;
+    /* Skip the dispatch thread (0) */
+    tid++;
+    LIBEVENT_THREAD *thread = threads + tid;
+
+    last_thread = tid;
 
     item->sfd = sfd;
     item->init_state = init_state;
     item->event_flags = event_flags;
     item->read_buffer_size = read_buffer_size;
     item->protocol = prot;
 
-    cq_push(&threads[thread].new_conn_queue, item);
+    cq_push(&thread->new_conn_queue, item);
 
     MEMCACHED_CONN_DISPATCH(sfd, threads[thread].thread_id);
-    if (write(threads[thread].notify_send_fd, "", 1) != 1) {
+    if (write(thread->notify_send_fd, "", 1) != 1) {
         perror("Writing to thread notify pipe");
     }
 }