Pushing weighted ketama code.

[awesomized/libmemcached] / libmemcached / memcached_hosts.c

diff --git a/libmemcached/memcached_hosts.c b/libmemcached/memcached_hosts.c
index d75da5d2d6114410ffaf1519e0469cef2b113821..55d7a49df403ea736e905a43f3576748c4069482 100644 (file)
--- a/libmemcached/memcached_hosts.c
+++ b/libmemcached/memcached_hosts.c
@@ -1,4 +1,5 @@
 #include "common.h"
+#include <math.h>
 
 /* Protoypes (static) */
 static memcached_return server_add(memcached_st *ptr, char *hostname, 
@@ -107,6 +108,12 @@ memcached_return update_continuum(memcached_st *ptr)
   uint32_t continuum_index= 0;
   uint32_t value;
   memcached_server_st *list;
+  uint32_t pointer_counter= 0;
+  uint32_t pointer_per_server= MEMCACHED_POINTS_PER_SERVER;
+  memcached_return rc;
+  uint64_t total_mem_bytes= 0;
+  memcached_stat_st *stat_p= NULL;
+  uint32_t is_ketama_weighted= 0;
 
   if (ptr->number_of_hosts > ptr->continuum_count)
   {
@@ -125,9 +132,29 @@ memcached_return update_continuum(memcached_st *ptr)
   }
 
   list = ptr->hosts;
+
+  is_ketama_weighted= memcached_behavior_get(ptr, MEMCACHED_BEHAVIOR_KETAMA_WEIGHTED);
+  if(is_ketama_weighted) 
+  {
+    stat_p = memcached_stat(ptr, NULL, &rc);
+    for (host_index = 0; host_index < ptr->number_of_hosts; ++host_index) 
+    {
+      list[host_index].limit_maxbytes= (stat_p + host_index)->limit_maxbytes;
+      total_mem_bytes += (stat_p + host_index)->limit_maxbytes;
+    }
+  }
+
   for (host_index = 0; host_index < ptr->number_of_hosts; ++host_index) 
   {
-    for(index= 1; index <= MEMCACHED_POINTS_PER_SERVER; ++index) 
+    if(is_ketama_weighted) 
+    {
+        float pct = (float)list[host_index].limit_maxbytes/ (float)total_mem_bytes;
+        pointer_per_server= floorf( pct * MEMCACHED_POINTS_PER_SERVER * (float)(ptr->number_of_hosts));
+#ifdef HAVE_DEBUG
+        printf("ketama_weighted:%s|%d|%llu|%u\n", list[host_index].hostname, list[host_index].port,  list[host_index].limit_maxbytes, pointer_per_server);
+#endif
+    }
+    for(index= 1; index <= pointer_per_server; ++index) 
     {
       char sort_host[MEMCACHED_MAX_HOST_SORT_LENGTH]= "";
       size_t sort_host_length;
@@ -135,14 +162,19 @@ memcached_return update_continuum(memcached_st *ptr)
       sort_host_length= snprintf(sort_host, MEMCACHED_MAX_HOST_SORT_LENGTH, "%s:%d-%d", 
                                  list[host_index].hostname, list[host_index].port, index);
       WATCHPOINT_ASSERT(sort_host_length);
-      value= generate_hash(ptr, sort_host, sort_host_length);
+      value= generate_hash_value(sort_host, sort_host_length, ptr->hash_continuum);
       ptr->continuum[continuum_index].index= host_index;
       ptr->continuum[continuum_index++].value= value;
     }
+    pointer_counter+= pointer_per_server;
   }
 
   WATCHPOINT_ASSERT(ptr->number_of_hosts * MEMCACHED_POINTS_PER_SERVER <= MEMCACHED_CONTINUUM_SIZE);
   qsort(ptr->continuum, ptr->number_of_hosts * MEMCACHED_POINTS_PER_SERVER, sizeof(memcached_continuum_item_st), continuum_item_cmp);
+
+  ptr->continuum_points_counter= pointer_counter;
+  memcached_stat_free(NULL, stat_p);
+
 #ifdef HAVE_DEBUG
   for (index= 0; index < ((ptr->number_of_hosts * MEMCACHED_POINTS_PER_SERVER) - 1); index++) 
   {