X-Git-Url: https://git.m6w6.name/?a=blobdiff_plain;f=libmemcached%2Fmemcached_hosts.c;h=2f1c4cc032e09a15183ee2e2d3217579f2042ab6;hb=7b548d21a8eafec0b830ad1bd6429cecd4eaeba8;hp=f816dd5be8d294bf37c19a48969d4f3b400fb150;hpb=151d417315c7ef9a1eaa0fe21150d8e0ec9eb440;p=awesomized%2Flibmemcached

diff --git a/libmemcached/memcached_hosts.c b/libmemcached/memcached_hosts.c
index f816dd5b..2f1c4cc0 100644
--- a/libmemcached/memcached_hosts.c
+++ b/libmemcached/memcached_hosts.c
@@ -1,34 +1,12 @@
 #include "common.h"
+#include <math.h>
 
 /* Protoypes (static) */
-static memcached_return server_add(memcached_st *ptr, char *hostname, 
+static memcached_return server_add(memcached_st *ptr, const char *hostname, 
                                    unsigned int port,
+                                   uint32_t weight,
                                    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)
 {
@@ -40,29 +18,40 @@ static int compare_servers(const void *p1, const void *p2)
 
   if (return_value == 0)
   {
-    if (a->port > b->port)
-      return_value++;
-    else
-      return_value--;
+    return_value= (int) (a->port - b->port);
   }
 
   return return_value;
 }
 
-static void host_reset(memcached_st *ptr, memcached_server_st *host, 
-                       char *hostname, unsigned int port,
-                       memcached_connection type)
+static void sort_hosts(memcached_st *ptr)
 {
-  memset(host,  0, sizeof(memcached_server_st));
-  strncpy(host->hostname, hostname, MEMCACHED_MAX_HOST_LENGTH - 1);
-  host->root= ptr ? ptr : NULL;
-  host->port= port;
-  host->fd= -1;
-  host->type= type;
-  host->read_ptr= host->read_buffer;
-  if (ptr)
-    host->next_retry= ptr->retry_timeout;
-  host->sockaddr_inited= MEMCACHED_NOT_ALLOCATED;
+  if (ptr->number_of_hosts)
+  {
+    qsort(ptr->hosts, ptr->number_of_hosts, sizeof(memcached_server_st), compare_servers);
+    ptr->hosts[0].count= ptr->number_of_hosts;
+  }
+}
+
+
+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;
+  case MEMCACHED_DISTRIBUTION_RANDOM:
+    break;
+  default:
+    WATCHPOINT_ASSERT(0); /* We have added a distribution without extending the logic */
+  }
+
+  return MEMCACHED_SUCCESS;
 }
 
 void server_list_free(memcached_st *ptr, memcached_server_st *servers)
@@ -74,14 +63,200 @@ 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)
+  if (ptr)
     ptr->call_free(ptr, servers);
   else
     free(servers);
 }
 
+static uint32_t ketama_server_hash(const char *key, unsigned int key_length, int alignment)
+{
+  unsigned char results[16];
+  
+  md5_signature((unsigned char*)key, key_length, results);
+  return ((uint32_t) (results[3 + alignment * 4] & 0xFF) << 24)
+    | ((uint32_t) (results[2 + alignment * 4] & 0xFF) << 16)
+    | ((uint32_t) (results[1 + alignment * 4] & 0xFF) << 8)
+    | (results[0 + alignment * 4] & 0xFF);
+}
+
+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 host_index;
+  uint32_t continuum_index= 0;
+  uint32_t value;
+  memcached_server_st *list;
+  uint32_t pointer_index;
+  uint32_t pointer_counter= 0;
+  uint32_t pointer_per_server= MEMCACHED_POINTS_PER_SERVER;
+  uint32_t pointer_per_hash= 1;
+  uint64_t total_weight= 0;
+  uint32_t is_ketama_weighted= 0;
+  uint32_t is_auto_ejecting= 0;
+  uint32_t points_per_server= 0;
+  uint32_t live_servers= 0;
+  struct timeval now;
+
+  if (gettimeofday(&now, NULL) != 0)
+  {
+    ptr->cached_errno = errno;
+    return MEMCACHED_ERRNO;
+  }
+
+  list = ptr->hosts;
+
+  /* count live servers (those without a retry delay set) */
+  is_auto_ejecting= memcached_behavior_get(ptr, MEMCACHED_BEHAVIOR_AUTO_EJECT_HOSTS);
+  if (is_auto_ejecting)
+  {
+    live_servers= 0;
+    ptr->next_distribution_rebuild= 0;
+    for (host_index= 0; host_index < ptr->number_of_hosts; ++host_index)
+    {
+      if (list[host_index].next_retry <= now.tv_sec)
+        live_servers++;
+      else
+      {
+        if (ptr->next_distribution_rebuild == 0 || list[host_index].next_retry < ptr->next_distribution_rebuild)
+          ptr->next_distribution_rebuild= list[host_index].next_retry;
+      }
+    }
+  }
+  else
+    live_servers= ptr->number_of_hosts;
+
+  is_ketama_weighted= memcached_behavior_get(ptr, MEMCACHED_BEHAVIOR_KETAMA_WEIGHTED);
+  points_per_server= is_ketama_weighted ? MEMCACHED_POINTS_PER_SERVER_KETAMA : MEMCACHED_POINTS_PER_SERVER;
+
+  if (live_servers == 0)
+    return MEMCACHED_SUCCESS;
+
+  if (live_servers > ptr->continuum_count)
+  {
+    memcached_continuum_item_st *new_ptr;
+
+    new_ptr= ptr->call_realloc(ptr, ptr->continuum, 
+                               sizeof(memcached_continuum_item_st) * (live_servers + MEMCACHED_CONTINUUM_ADDITION) * points_per_server);
+
+    if (new_ptr == 0)
+      return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
+
+    ptr->continuum= new_ptr;
+    ptr->continuum_count= live_servers + MEMCACHED_CONTINUUM_ADDITION;
+  }
+
+  if (is_ketama_weighted) 
+  {
+    for (host_index = 0; host_index < ptr->number_of_hosts; ++host_index) 
+    {
+      if (list[host_index].weight == 0)
+      {
+        list[host_index].weight = 1;
+      }
+      if (!is_auto_ejecting || list[host_index].next_retry <= now.tv_sec)
+        total_weight += list[host_index].weight;
+    }
+  }
+
+  for (host_index = 0; host_index < ptr->number_of_hosts; ++host_index) 
+  {
+    if (is_auto_ejecting && list[host_index].next_retry > now.tv_sec)
+      continue;
+
+    if (is_ketama_weighted) 
+    {
+        float pct = (float)list[host_index].weight / (float)total_weight;
+        pointer_per_server= floorf(pct * MEMCACHED_POINTS_PER_SERVER_KETAMA / 4 * (float)live_servers + 0.0000000001) * 4;
+        pointer_per_hash= 4;
+#ifdef DEBUG
+        printf("ketama_weighted:%s|%d|%llu|%u\n", 
+               list[host_index].hostname, 
+               list[host_index].port,  
+               (unsigned long long)list[host_index].weight, 
+               pointer_per_server);
+#endif
+    }
+    for (pointer_index= 1;
+         pointer_index <= pointer_per_server / pointer_per_hash;
+         ++pointer_index) 
+    {
+      char sort_host[MEMCACHED_MAX_HOST_SORT_LENGTH]= "";
+      size_t sort_host_length;
+
+      if (list[host_index].port == MEMCACHED_DEFAULT_PORT)
+      {
+        sort_host_length= snprintf(sort_host, MEMCACHED_MAX_HOST_SORT_LENGTH,
+                                   "%s-%d",
+                                   list[host_index].hostname,
+                                   pointer_index - 1);
+
+      }
+      else
+      {
+        sort_host_length= snprintf(sort_host, MEMCACHED_MAX_HOST_SORT_LENGTH,
+                                   "%s:%d-%d", 
+                                   list[host_index].hostname,
+                                   list[host_index].port, pointer_index - 1);
+      }
+      WATCHPOINT_ASSERT(sort_host_length);
+
+      if (is_ketama_weighted)
+      {
+        unsigned int i;
+        for (i = 0; i < pointer_per_hash; i++)
+        {
+          value= ketama_server_hash(sort_host, sort_host_length, i);
+          ptr->continuum[continuum_index].index= host_index;
+          ptr->continuum[continuum_index++].value= value;
+        }
+      }
+      else
+      {
+        value= memcached_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 * MEMCACHED_POINTS_PER_SERVER <= MEMCACHED_CONTINUUM_SIZE);
+  ptr->continuum_points_counter= pointer_counter;
+  qsort(ptr->continuum, ptr->continuum_points_counter, sizeof(memcached_continuum_item_st), continuum_item_cmp);
+
+#ifdef DEBUG
+  for (pointer_index= 0; ptr->number_of_hosts && pointer_index < ((live_servers * MEMCACHED_POINTS_PER_SERVER) - 1); pointer_index++) 
+  {
+    WATCHPOINT_ASSERT(ptr->continuum[pointer_index].value <= ptr->continuum[pointer_index + 1].value);
+  }
+#endif
+
+  return MEMCACHED_SUCCESS;
+}
+
+
 memcached_return memcached_server_push(memcached_st *ptr, memcached_server_st *list)
 {
   unsigned int x;
@@ -92,49 +267,60 @@ memcached_return memcached_server_push(memcached_st *ptr, memcached_server_st *l
     return MEMCACHED_SUCCESS;
 
   count= list[0].count;
-
-  if (ptr->call_realloc)
-    new_host_list= 
-      (memcached_server_st *)ptr->call_realloc(ptr, ptr->hosts, 
-                                               sizeof(memcached_server_st) * (count + ptr->number_of_hosts));
-  else
-    new_host_list= 
-      (memcached_server_st *)realloc(ptr->hosts, 
-                                     sizeof(memcached_server_st) * (count + ptr->number_of_hosts));
+  new_host_list= ptr->call_realloc(ptr, ptr->hosts, 
+                                   sizeof(memcached_server_st) * (count + ptr->number_of_hosts));
 
   if (!new_host_list)
     return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 
   ptr->hosts= new_host_list;
-                                   
+
   for (x= 0; x < count; x++)
   {
+    if ((ptr->flags & MEM_USE_UDP && list[x].type != MEMCACHED_CONNECTION_UDP)
+            || ((list[x].type == MEMCACHED_CONNECTION_UDP)
+            && ! (ptr->flags & MEM_USE_UDP)) )
+      return MEMCACHED_INVALID_HOST_PROTOCOL;
+
     WATCHPOINT_ASSERT(list[x].hostname[0] != 0);
-    host_reset(ptr, &ptr->hosts[ptr->number_of_hosts], list[x].hostname, 
-               list[x].port, list[x].type);
+    memcached_server_create(ptr, &ptr->hosts[ptr->number_of_hosts]);
+    /* TODO check return type */
+    (void)memcached_server_create_with(ptr, &ptr->hosts[ptr->number_of_hosts], list[x].hostname, 
+                                       list[x].port, list[x].weight, list[x].type);
     ptr->number_of_hosts++;
   }
   ptr->hosts[0].count= ptr->number_of_hosts;
 
-  if (ptr->number_of_hosts > 1 && ptr->flags & MEMCACHED_BEHAVIOR_SORT_HOSTS)
-    qsort(ptr->hosts, ptr->number_of_hosts, sizeof(memcached_server_st), compare_servers);
-
-  rebalance_wheel(ptr);
+  return run_distribution(ptr);
+}
 
-  return MEMCACHED_SUCCESS;
+memcached_return memcached_server_add_unix_socket(memcached_st *ptr, 
+                                                  const char *filename)
+{
+  return memcached_server_add_unix_socket_with_weight(ptr, filename, 0);
 }
 
-memcached_return memcached_server_add_unix_socket(memcached_st *ptr, char *filename)
+memcached_return memcached_server_add_unix_socket_with_weight(memcached_st *ptr, 
+                                                              const char *filename, 
+                                                              uint32_t weight)
 {
   if (!filename)
     return MEMCACHED_FAILURE;
 
-  return server_add(ptr, filename, 0, MEMCACHED_CONNECTION_UNIX_SOCKET);
+  return server_add(ptr, filename, 0, weight, MEMCACHED_CONNECTION_UNIX_SOCKET);
 }
 
 memcached_return memcached_server_add_udp(memcached_st *ptr, 
-                                          char *hostname,
+                                          const char *hostname,
                                           unsigned int port)
+{
+  return memcached_server_add_udp_with_weight(ptr, hostname, port, 0);
+}
+
+memcached_return memcached_server_add_udp_with_weight(memcached_st *ptr, 
+                                                      const char *hostname,
+                                                      unsigned int port,
+                                                      uint32_t weight)
 {
   if (!port)
     port= MEMCACHED_DEFAULT_PORT; 
@@ -142,59 +328,95 @@ memcached_return memcached_server_add_udp(memcached_st *ptr,
   if (!hostname)
     hostname= "localhost"; 
 
-  return server_add(ptr, hostname, port, MEMCACHED_CONNECTION_UDP);
+  return server_add(ptr, hostname, port, weight, MEMCACHED_CONNECTION_UDP);
 }
 
 memcached_return memcached_server_add(memcached_st *ptr, 
-                                      char *hostname, 
+                                      const char *hostname, 
                                       unsigned int port)
+{
+  return memcached_server_add_with_weight(ptr, hostname, port, 0);
+}
+
+memcached_return memcached_server_add_with_weight(memcached_st *ptr, 
+                                                  const char *hostname, 
+                                                  unsigned int port,
+                                                  uint32_t weight)
 {
   if (!port)
     port= MEMCACHED_DEFAULT_PORT; 
 
   if (!hostname)
-    hostname= "localhost"; 
+    hostname= "localhost";
 
-  return server_add(ptr, hostname, port, MEMCACHED_CONNECTION_TCP);
+  return server_add(ptr, hostname, port, weight, MEMCACHED_CONNECTION_TCP);
 }
 
-static memcached_return server_add(memcached_st *ptr, char *hostname, 
+static memcached_return server_add(memcached_st *ptr, const char *hostname, 
                                    unsigned int port,
+                                   uint32_t weight,
                                    memcached_connection type)
 {
   memcached_server_st *new_host_list;
-  LIBMEMCACHED_MEMCACHED_SERVER_ADD_START();
 
+  if ( (ptr->flags & MEM_USE_UDP && type != MEMCACHED_CONNECTION_UDP)
+      || ( (type == MEMCACHED_CONNECTION_UDP) && !(ptr->flags & MEM_USE_UDP) ) )
+    return MEMCACHED_INVALID_HOST_PROTOCOL;
+  
+  new_host_list= ptr->call_realloc(ptr, ptr->hosts, 
+                                   sizeof(memcached_server_st) * (ptr->number_of_hosts+1));
 
-  if (ptr->call_realloc)
-    new_host_list= (memcached_server_st *)ptr->call_realloc(ptr, ptr->hosts, 
-                                                            sizeof(memcached_server_st) * (ptr->number_of_hosts+1));
-  else
-    new_host_list= (memcached_server_st *)realloc(ptr->hosts, 
-                                                  sizeof(memcached_server_st) * (ptr->number_of_hosts+1));
   if (new_host_list == NULL)
     return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 
   ptr->hosts= new_host_list;
 
-  host_reset(ptr, &ptr->hosts[ptr->number_of_hosts], hostname, port, type);
+  /* TODO: Check return type */
+  (void)memcached_server_create_with(ptr, &ptr->hosts[ptr->number_of_hosts], hostname, port, weight, type);
   ptr->number_of_hosts++;
+  ptr->hosts[0].count= ptr->number_of_hosts;
 
-  if (ptr->number_of_hosts > 1 && ptr->flags & MEMCACHED_BEHAVIOR_SORT_HOSTS)
-    qsort(ptr->hosts, ptr->number_of_hosts, sizeof(memcached_server_st), compare_servers);
+  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, host_index;
+  memcached_st *ptr= st_ptr->root;
+  memcached_server_st *list= ptr->hosts;
 
-  rebalance_wheel(ptr);
+  for (x= 0, host_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) 
+    {
+      if (host_index != x)
+        memcpy(list+host_index, list+x, sizeof(memcached_server_st));
+      host_index++;
+    } 
+  }
+  ptr->number_of_hosts= host_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;
 }
 
 memcached_server_st *memcached_server_list_append(memcached_server_st *ptr, 
-                                                  char *hostname, unsigned int port, 
+                                                  const char *hostname, unsigned int port,
                                                   memcached_return *error)
+{
+  return memcached_server_list_append_with_weight(ptr, hostname, port, 0, error);
+}
+
+memcached_server_st *memcached_server_list_append_with_weight(memcached_server_st *ptr, 
+                                                              const char *hostname, unsigned int port,
+                                                              uint32_t weight, 
+                                                              memcached_return *error)
 {
   unsigned int count;
   memcached_server_st *new_host_list;
@@ -219,7 +441,8 @@ memcached_server_st *memcached_server_list_append(memcached_server_st *ptr,
     return NULL;
   }
 
-  host_reset(NULL, &new_host_list[count-1], hostname, port, MEMCACHED_CONNECTION_TCP);
+  /* TODO: Check return type */
+  memcached_server_create_with(NULL, &new_host_list[count-1], hostname, port, weight, MEMCACHED_CONNECTION_TCP);
 
   /* Backwards compatibility hack */
   new_host_list[0].count= count;