#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)
{
if (return_value == 0)
{
- if (a->port > b->port)
- return_value++;
- else
- return_value--;
+ return_value= (int) (a->port - b->port);
}
return return_value;
}
-void sort_hosts(memcached_st *ptr)
+static void sort_hosts(memcached_st *ptr)
{
if (ptr->number_of_hosts)
{
}
}
-static void host_reset(memcached_st *ptr, memcached_server_st *host,
- char *hostname, unsigned int port,
- memcached_connection type)
+
+memcached_return run_distribution(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;
+ 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)
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);
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 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;
+ 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;
+
+ if (ptr->call_realloc)
+ new_ptr= (memcached_continuum_item_st *)ptr->call_realloc(ptr, ptr->continuum,
+ sizeof(memcached_continuum_item_st) * (live_servers + MEMCACHED_CONTINUUM_ADDITION) * points_per_server);
+ else
+ new_ptr= (memcached_continuum_item_st *)realloc(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 HAVE_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 (index= 1; index <= pointer_per_server / pointer_per_hash; ++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, 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, index - 1);
+ }
+ WATCHPOINT_ASSERT(sort_host_length);
+
+ if (is_ketama_weighted)
+ {
+ 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 HAVE_DEBUG
+ for (index= 0; ptr->number_of_hosts && index < ((live_servers * 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;
return MEMCACHED_SUCCESS;
count= list[0].count;
-
if (ptr->call_realloc)
new_host_list=
(memcached_server_st *)ptr->call_realloc(ptr, ptr->hosts,
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->flags & MEM_USE_SORT_HOSTS)
- sort_hosts(ptr);
-
- 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;
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;
+
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));
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->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)
+ {
+ if (index != x)
+ 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;
}
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;
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;
projects / awesomized / libmemcached / blobdiff