X-Git-Url: https://git.m6w6.name/?a=blobdiff_plain;ds=inline;f=libmemcached%2Fmemcached_hosts.c;h=54440d3582607cd6115245fd906bfc9ba7af7eff;hb=4c88db14024912f86c1628f6bd8a05f9a6c5559b;hp=bdbdcbb684898eaeb130994e44f037c48bb79c23;hpb=a7d4d06052df02ae2eff8694e8ed6cc991b83eee;p=m6w6%2Flibmemcached

diff --git a/libmemcached/memcached_hosts.c b/libmemcached/memcached_hosts.c
index bdbdcbb6..54440d35 100644
--- a/libmemcached/memcached_hosts.c
+++ b/libmemcached/memcached_hosts.c
@@ -1,34 +1,11 @@
 #include "common.h"
+#include <math.h>
 
 /* Protoypes (static) */
 static memcached_return server_add(memcached_st *ptr, char *hostname, 
                                    unsigned int port,
                                    memcached_connection type);
-
-#define MEMCACHED_WHEEL_SIZE 1024
-#define MEMCACHED_STRIDE 4
-static void rebalance_wheel(memcached_st *ptr)
-{
-  unsigned int x;
-  unsigned int y;
-  unsigned int latch;
-
-  /* Seed the Wheel */
-  memset(ptr->wheel, 0, sizeof(unsigned int) * MEMCACHED_WHEEL_SIZE);
-
-  for (latch= y= x= 0; x < MEMCACHED_WHEEL_SIZE; x++, latch++)
-  {
-    if (latch == MEMCACHED_STRIDE)
-    {
-      y++;
-      if (y == ptr->number_of_hosts)
-        y= 0;
-      latch= 0;
-    }
-
-    ptr->wheel[x]= y;
-  }
-}
+memcached_return update_continuum(memcached_st *ptr);
 
 static int compare_servers(const void *p1, const void *p2)
 {
@@ -55,6 +32,25 @@ void sort_hosts(memcached_st *ptr)
   }
 }
 
+
+memcached_return run_distribution(memcached_st *ptr)
+{
+  switch (ptr->distribution) 
+  {
+  case MEMCACHED_DISTRIBUTION_CONSISTENT:
+  case MEMCACHED_DISTRIBUTION_CONSISTENT_KETAMA:
+    return update_continuum(ptr);
+  case MEMCACHED_DISTRIBUTION_MODULA:
+    if (ptr->flags & MEM_USE_SORT_HOSTS)
+      sort_hosts(ptr);
+    break;
+  default:
+    WATCHPOINT_ASSERT(0); /* We have added a distribution without extending the logic */
+  }
+
+  return MEMCACHED_SUCCESS;
+}
+
 static void host_reset(memcached_st *ptr, memcached_server_st *host, 
                        char *hostname, unsigned int port,
                        memcached_connection type)
@@ -80,7 +76,10 @@ void server_list_free(memcached_st *ptr, memcached_server_st *servers)
 
   for (x= 0; x < servers->count; x++)
     if (servers[x].address_info)
+    {
       freeaddrinfo(servers[x].address_info);
+      servers[x].address_info= NULL;
+    }
 
   if (ptr && ptr->call_free)
     ptr->call_free(ptr, servers);
@@ -88,6 +87,110 @@ void server_list_free(memcached_st *ptr, memcached_server_st *servers)
     free(servers);
 }
 
+static int continuum_item_cmp(const void *t1, const void *t2)
+{
+  memcached_continuum_item_st *ct1= (memcached_continuum_item_st *)t1;
+  memcached_continuum_item_st *ct2= (memcached_continuum_item_st *)t2;
+
+  /* Why 153? Hmmm... */
+  WATCHPOINT_ASSERT(ct1->value != 153);
+  if (ct1->value == ct2->value)
+    return 0;
+  else if (ct1->value > ct2->value)
+    return 1;
+  else
+    return -1;
+}
+
+memcached_return update_continuum(memcached_st *ptr)
+{
+  uint32_t index;
+  uint32_t host_index;
+  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)
+  {
+    memcached_continuum_item_st *new_ptr;
+
+    if (ptr->call_realloc)
+      new_ptr= (memcached_continuum_item_st *)ptr->call_realloc(ptr, ptr->continuum, sizeof(memcached_continuum_item_st) * (ptr->number_of_hosts + MEMCACHED_CONTINUUM_ADDITION) * MEMCACHED_POINTS_PER_SERVER);
+    else
+      new_ptr= (memcached_continuum_item_st *)realloc(ptr->continuum, sizeof(memcached_continuum_item_st) * (ptr->number_of_hosts + MEMCACHED_CONTINUUM_ADDITION) * MEMCACHED_POINTS_PER_SERVER);
+
+    if (new_ptr == 0)
+      return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
+
+    ptr->continuum= new_ptr;
+    ptr->continuum_count= ptr->number_of_hosts + MEMCACHED_CONTINUUM_ADDITION;
+  }
+
+  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) 
+  {
+    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;
+
+      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_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);
+  WATCHPOINT_ASSERT(ptr->continuum);
+  WATCHPOINT_ASSERT(ptr->number_of_hosts);
+  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;
+  if (stat_p)
+    memcached_stat_free(NULL, stat_p);
+
+#ifdef HAVE_DEBUG
+  for (index= 0; index < ((ptr->number_of_hosts * MEMCACHED_POINTS_PER_SERVER) - 1); index++) 
+  {
+    WATCHPOINT_ASSERT(ptr->continuum[index].value <= ptr->continuum[index + 1].value);
+  }
+#endif
+
+  return MEMCACHED_SUCCESS;
+}
+
+
 memcached_return memcached_server_push(memcached_st *ptr, memcached_server_st *list)
 {
   unsigned int x;
@@ -122,12 +225,7 @@ memcached_return memcached_server_push(memcached_st *ptr, memcached_server_st *l
   }
   ptr->hosts[0].count= ptr->number_of_hosts;
 
-  if (ptr->flags & MEM_USE_SORT_HOSTS)
-    sort_hosts(ptr);
-
-  rebalance_wheel(ptr);
-
-  return MEMCACHED_SUCCESS;
+  return run_distribution(ptr);
 }
 
 memcached_return memcached_server_add_unix_socket(memcached_st *ptr, char *filename)
@@ -169,8 +267,6 @@ static memcached_return server_add(memcached_st *ptr, char *hostname,
                                    memcached_connection type)
 {
   memcached_server_st *new_host_list;
-  LIBMEMCACHED_MEMCACHED_SERVER_ADD_START();
-
 
   if (ptr->call_realloc)
     new_host_list= (memcached_server_st *)ptr->call_realloc(ptr, ptr->hosts, 
@@ -185,15 +281,33 @@ static memcached_return server_add(memcached_st *ptr, char *hostname,
 
   host_reset(ptr, &ptr->hosts[ptr->number_of_hosts], hostname, port, type);
   ptr->number_of_hosts++;
+  ptr->hosts[0].count= ptr->number_of_hosts;
 
-  if (ptr->flags & MEM_USE_SORT_HOSTS)
-    sort_hosts(ptr);
+  return run_distribution(ptr);
+}
 
-  ptr->hosts[0].count= ptr->number_of_hosts;
+memcached_return memcached_server_remove(memcached_server_st *st_ptr)
+{
+  uint32_t x, index;
+  memcached_st *ptr= st_ptr->root;
+  memcached_server_st *list= ptr->hosts;
 
-  rebalance_wheel(ptr);
+  for (x= 0, index= 0; x < ptr->number_of_hosts; x++) 
+  {
+    if (strncmp(list[x].hostname, st_ptr->hostname, MEMCACHED_MAX_HOST_LENGTH)!=0 || list[x].port != st_ptr->port) 
+    {
+      memcpy(list+index, list+x, sizeof(memcached_server_st));
+      index++;
+    } 
+  }
+  ptr->number_of_hosts= index;
 
-  LIBMEMCACHED_MEMCACHED_SERVER_ADD_END();
+  if (st_ptr->address_info) 
+  {
+    freeaddrinfo(st_ptr->address_info);
+    st_ptr->address_info= NULL;
+  }
+  run_distribution(ptr);
 
   return MEMCACHED_SUCCESS;
 }