X-Git-Url: https://git.m6w6.name/?a=blobdiff_plain;f=libmemcached%2Fmemcached_get.c;h=9ba1388d4b5dbcb606497f022af44849d150dbc2;hb=75bbebb7976acf3cbfdf1525599180cf49e67f56;hp=53c76f4bd67279599c5d6296098a8f970582d683;hpb=35a37b8f10e31646efb89325331c171ecae87d78;p=m6w6%2Flibmemcached diff --git a/libmemcached/memcached_get.c b/libmemcached/memcached_get.c index 53c76f4b..9ba1388d 100644 --- a/libmemcached/memcached_get.c +++ b/libmemcached/memcached_get.c @@ -1,32 +1,32 @@ #include "common.h" #include "memcached_io.h" -/* +/* What happens if no servers exist? */ -char *memcached_get(memcached_st *ptr, const char *key, - size_t key_length, - size_t *value_length, +char *memcached_get(memcached_st *ptr, const char *key, + size_t key_length, + size_t *value_length, uint32_t *flags, memcached_return *error) { - return memcached_get_by_key(ptr, NULL, 0, key, key_length, value_length, + return memcached_get_by_key(ptr, NULL, 0, key, key_length, value_length, flags, error); } -static memcached_return memcached_mget_by_key_real(memcached_st *ptr, - const char *master_key, - size_t master_key_length, - const char **keys, - size_t *key_length, - size_t number_of_keys, - bool mget_mode); - -char *memcached_get_by_key(memcached_st *ptr, - const char *master_key, - size_t master_key_length, +static memcached_return memcached_mget_by_key_real(memcached_st *ptr, + const char *master_key, + size_t master_key_length, + const char * const *keys, + const size_t *key_length, + size_t number_of_keys, + bool mget_mode); + +char *memcached_get_by_key(memcached_st *ptr, + const char *master_key, + size_t master_key_length, const char *key, size_t key_length, - size_t *value_length, + size_t *value_length, uint32_t *flags, memcached_return *error) { @@ -42,12 +42,11 @@ char *memcached_get_by_key(memcached_st *ptr, } /* Request the key */ - *error= memcached_mget_by_key_real(ptr, - master_key, - master_key_length, - (const char **)&key, &key_length, 1, false); + *error= memcached_mget_by_key_real(ptr, master_key, master_key_length, + (const char * const *)&key, + &key_length, 1, false); - value= memcached_fetch(ptr, NULL, NULL, + value= memcached_fetch(ptr, NULL, NULL, value_length, flags, error); /* This is for historical reasons */ if (*error == MEMCACHED_END) @@ -61,7 +60,7 @@ char *memcached_get_by_key(memcached_st *ptr, memcached_result_reset(&ptr->result); rc= ptr->get_key_failure(ptr, key, key_length, &ptr->result); - + /* On all failure drop to returning NULL */ if (rc == MEMCACHED_SUCCESS || rc == MEMCACHED_BUFFERED) { @@ -72,7 +71,7 @@ char *memcached_get_by_key(memcached_st *ptr, if (latch == 0) memcached_behavior_set(ptr, MEMCACHED_BEHAVIOR_BUFFER_REQUESTS, 1); - rc= memcached_set(ptr, key, key_length, + rc= memcached_set(ptr, key, key_length, memcached_result_value(&ptr->result), memcached_result_length(&ptr->result), 0, memcached_result_flags(&ptr->result)); @@ -82,7 +81,7 @@ char *memcached_get_by_key(memcached_st *ptr, } else { - rc= memcached_set(ptr, key, key_length, + rc= memcached_set(ptr, key, key_length, memcached_result_value(&ptr->result), memcached_result_length(&ptr->result), 0, memcached_result_flags(&ptr->result)); @@ -101,16 +100,17 @@ char *memcached_get_by_key(memcached_st *ptr, return NULL; } - (void)memcached_fetch(ptr, NULL, NULL, - &dummy_length, &dummy_flags, + (void)memcached_fetch(ptr, NULL, NULL, + &dummy_length, &dummy_flags, &dummy_error); WATCHPOINT_ASSERT(dummy_length == 0); return value; } -memcached_return memcached_mget(memcached_st *ptr, - const char **keys, size_t *key_length, +memcached_return memcached_mget(memcached_st *ptr, + const char * const *keys, + const size_t *key_length, size_t number_of_keys) { return memcached_mget_by_key(ptr, NULL, 0, keys, key_length, number_of_keys); @@ -119,17 +119,18 @@ memcached_return memcached_mget(memcached_st *ptr, static memcached_return binary_mget_by_key(memcached_st *ptr, unsigned int master_server_key, bool is_master_key_set, - const char **keys, size_t *key_length, + const char * const *keys, + const size_t *key_length, size_t number_of_keys, bool mget_mode); -static memcached_return memcached_mget_by_key_real(memcached_st *ptr, - const char *master_key, - size_t master_key_length, - const char **keys, - size_t *key_length, - size_t number_of_keys, - bool mget_mode) +static memcached_return memcached_mget_by_key_real(memcached_st *ptr, + const char *master_key, + size_t master_key_length, + const char * const *keys, + const size_t *key_length, + size_t number_of_keys, + bool mget_mode) { unsigned int x; memcached_return rc= MEMCACHED_NOTFOUND; @@ -155,13 +156,13 @@ static memcached_return memcached_mget_by_key_real(memcached_st *ptr, if (master_key && master_key_length) { - if ((ptr->flags & MEM_VERIFY_KEY) && (memcached_key_test((const char **)&master_key, &master_key_length, 1) == MEMCACHED_BAD_KEY_PROVIDED)) + if ((ptr->flags & MEM_VERIFY_KEY) && (memcached_key_test((const char * const *)&master_key, &master_key_length, 1) == MEMCACHED_BAD_KEY_PROVIDED)) return MEMCACHED_BAD_KEY_PROVIDED; master_server_key= memcached_generate_hash(ptr, master_key, master_key_length); is_master_key_set= true; } - /* + /* Here is where we pay for the non-block API. We need to remove any data sitting in the queue before we start our get. @@ -180,9 +181,9 @@ static memcached_return memcached_mget_by_key_real(memcached_st *ptr, (void)memcached_response(&ptr->hosts[x], buffer, MEMCACHED_DEFAULT_COMMAND_SIZE, &ptr->result); } } - + if (ptr->flags & MEM_BINARY_PROTOCOL) - return binary_mget_by_key(ptr, master_server_key, is_master_key_set, keys, + return binary_mget_by_key(ptr, master_server_key, is_master_key_set, keys, key_length, number_of_keys, mget_mode); if (ptr->flags & MEM_SUPPORT_CAS) @@ -191,7 +192,7 @@ static memcached_return memcached_mget_by_key_real(memcached_st *ptr, get_command_length= 5; } - /* + /* If a server fails we warn about errors and start all over with sending keys to the server. */ @@ -266,26 +267,39 @@ static memcached_return memcached_mget_by_key_real(memcached_st *ptr, return rc; } -memcached_return memcached_mget_by_key(memcached_st *ptr, - const char *master_key, +memcached_return memcached_mget_by_key(memcached_st *ptr, + const char *master_key, size_t master_key_length, - const char **keys, - size_t *key_length, + const char * const *keys, + const size_t *key_length, size_t number_of_keys) { - return memcached_mget_by_key_real(ptr, master_key, master_key_length, keys, + return memcached_mget_by_key_real(ptr, master_key, master_key_length, keys, key_length, number_of_keys, true); } memcached_return memcached_mget_execute(memcached_st *ptr, - const char *master_key, - size_t master_key_length, - const char **keys, - size_t *key_length, + const char * const *keys, + const size_t *key_length, size_t number_of_keys, memcached_execute_function *callback, void *context, unsigned int number_of_callbacks) +{ + return memcached_mget_execute_by_key(ptr, NULL, 0, keys, key_length, + number_of_keys, callback, + context, number_of_callbacks); +} + +memcached_return memcached_mget_execute_by_key(memcached_st *ptr, + const char *master_key, + size_t master_key_length, + const char * const *keys, + const size_t *key_length, + size_t number_of_keys, + memcached_execute_function *callback, + void *context, + unsigned int number_of_callbacks) { if ((ptr->flags & MEM_BINARY_PROTOCOL) == 0) return MEMCACHED_NOT_SUPPORTED; @@ -295,7 +309,7 @@ memcached_return memcached_mget_execute(memcached_st *ptr, memcached_callback_st cb= { .callback= callback, .context= context, - .number_of_callback= 1 + .number_of_callback= number_of_callbacks }; ptr->callbacks= &cb; @@ -308,7 +322,8 @@ memcached_return memcached_mget_execute(memcached_st *ptr, static memcached_return simple_binary_mget(memcached_st *ptr, unsigned int master_server_key, bool is_master_key_set, - const char **keys, size_t *key_length, + const char * const *keys, + const size_t *key_length, size_t number_of_keys, bool mget_mode) { memcached_return rc= MEMCACHED_NOTFOUND; @@ -316,11 +331,11 @@ static memcached_return simple_binary_mget(memcached_st *ptr, int flush= number_of_keys == 1; - /* + /* If a server fails we warn about errors and start all over with sending keys to the server. */ - for (x= 0; x < number_of_keys; x++) + for (x= 0; x < number_of_keys; x++) { unsigned int server_key; @@ -329,13 +344,13 @@ static memcached_return simple_binary_mget(memcached_st *ptr, else server_key= memcached_generate_hash(ptr, keys[x], key_length[x]); - if (memcached_server_response_count(&ptr->hosts[server_key]) == 0) + if (memcached_server_response_count(&ptr->hosts[server_key]) == 0) { rc= memcached_connect(&ptr->hosts[server_key]); - if (rc != MEMCACHED_SUCCESS) + if (rc != MEMCACHED_SUCCESS) continue; } - + protocol_binary_request_getk request= {.bytes= {0}}; request.message.header.request.magic= PROTOCOL_BINARY_REQ; if (mget_mode) @@ -356,26 +371,26 @@ static memcached_return simple_binary_mget(memcached_st *ptr, request.message.header.request.keylen= htons((uint16_t)key_length[x]); request.message.header.request.datatype= PROTOCOL_BINARY_RAW_BYTES; request.message.header.request.bodylen= htonl((uint32_t) key_length[x]); - + if ((memcached_io_write(&ptr->hosts[server_key], request.bytes, sizeof(request.bytes), 0) == -1) || - (memcached_io_write(&ptr->hosts[server_key], keys[x], - key_length[x], (char) flush) == -1)) + (memcached_io_write(&ptr->hosts[server_key], keys[x], + key_length[x], (char) flush) == -1)) { memcached_server_response_reset(&ptr->hosts[server_key]); rc= MEMCACHED_SOME_ERRORS; continue; } - + /* We just want one pending response per server */ - memcached_server_response_reset(&ptr->hosts[server_key]); - memcached_server_response_increment(&ptr->hosts[server_key]); + memcached_server_response_reset(&ptr->hosts[server_key]); + memcached_server_response_increment(&ptr->hosts[server_key]); if ((x > 0 && x == ptr->io_key_prefetch) && memcached_flush_buffers(ptr) != MEMCACHED_SUCCESS) rc= MEMCACHED_SOME_ERRORS; } - if (mget_mode) + if (mget_mode) { /* * Send a noop command to flush the buffers @@ -384,19 +399,19 @@ static memcached_return simple_binary_mget(memcached_st *ptr, request.message.header.request.magic= PROTOCOL_BINARY_REQ; request.message.header.request.opcode= PROTOCOL_BINARY_CMD_NOOP; request.message.header.request.datatype= PROTOCOL_BINARY_RAW_BYTES; - + for (x= 0; x < ptr->number_of_hosts; x++) - if (memcached_server_response_count(&ptr->hosts[x])) + if (memcached_server_response_count(&ptr->hosts[x])) { - if (memcached_io_write(&ptr->hosts[x], NULL, 0, 1) == -1) + if (memcached_io_write(&ptr->hosts[x], NULL, 0, 1) == -1) { memcached_server_response_reset(&ptr->hosts[x]); memcached_io_reset(&ptr->hosts[x]); rc= MEMCACHED_SOME_ERRORS; } - if (memcached_io_write(&ptr->hosts[x], request.bytes, - sizeof(request.bytes), 1) == -1) + if (memcached_io_write(&ptr->hosts[x], request.bytes, + sizeof(request.bytes), 1) == -1) { memcached_server_response_reset(&ptr->hosts[x]); memcached_io_reset(&ptr->hosts[x]); @@ -410,25 +425,35 @@ static memcached_return simple_binary_mget(memcached_st *ptr, } static memcached_return replication_binary_mget(memcached_st *ptr, - uint32_t* hash, bool* dead_servers, - const char **keys, size_t *key_length, - size_t number_of_keys, bool mget_mode) + uint32_t* hash, + bool* dead_servers, + const char *const *keys, + const size_t *key_length, + size_t number_of_keys) { memcached_return rc= MEMCACHED_NOTFOUND; - uint32_t x; + uint32_t x, start= 0; + uint64_t randomize_read= memcached_behavior_get(ptr, MEMCACHED_BEHAVIOR_RANDOMIZE_REPLICA_READ); - int flush= number_of_keys == 1; + if (randomize_read) + start= (uint32_t)random() % (uint32_t)(ptr->number_of_replicas + 1); + /* Loop for each replica */ for (uint32_t replica= 0; replica <= ptr->number_of_replicas; ++replica) { - bool success= true; - + bool success= true; + for (x= 0; x < number_of_keys; ++x) { if (hash[x] == ptr->number_of_hosts) continue; /* Already successfully sent */ uint32_t server= hash[x] + replica; + + /* In case of randomized reads */ + if (randomize_read && ((server + start) <= (hash[x] + ptr->number_of_replicas))) + server += start; + while (server >= ptr->number_of_hosts) server -= ptr->number_of_hosts; @@ -447,58 +472,39 @@ static memcached_return replication_binary_mget(memcached_st *ptr, } } - protocol_binary_request_getk request= {.bytes= {0}}; - request.message.header.request.magic= PROTOCOL_BINARY_REQ; - if (mget_mode) - request.message.header.request.opcode= PROTOCOL_BINARY_CMD_GETKQ; - else - request.message.header.request.opcode= PROTOCOL_BINARY_CMD_GETK; - - request.message.header.request.keylen= htons((uint16_t)key_length[x]); - request.message.header.request.datatype= PROTOCOL_BINARY_RAW_BYTES; - request.message.header.request.bodylen= htonl((uint32_t) key_length[x]); + protocol_binary_request_getk request= { + .message.header.request= { + .magic= PROTOCOL_BINARY_REQ, + .opcode= PROTOCOL_BINARY_CMD_GETK, + .keylen= htons((uint16_t)key_length[x]), + .datatype= PROTOCOL_BINARY_RAW_BYTES, + .bodylen= htonl((uint32_t)key_length[x]) + } + }; + /* + * We need to disable buffering to actually know that the request was + * successfully sent to the server (so that we should expect a result + * back). It would be nice to do this in buffered mode, but then it + * would be complex to handle all error situations if we got to send + * some of the messages, and then we failed on writing out some others + * and we used the callback interface from memcached_mget_execute so + * that we might have processed some of the responses etc. For now, + * just make sure we work _correctly_ + */ if ((memcached_io_write(&ptr->hosts[server], request.bytes, sizeof(request.bytes), 0) == -1) || (memcached_io_write(&ptr->hosts[server], keys[x], - key_length[x], (char) flush) == -1)) + key_length[x], 1) == -1)) { memcached_io_reset(&ptr->hosts[server]); dead_servers[server]= true; success= false; continue; } - /* we just want one pending response per server */ - memcached_server_response_reset(&ptr->hosts[server]); - memcached_server_response_increment(&ptr->hosts[server]); - } - if (mget_mode) - { - /* - * Send a noop command to flush the buffers - */ - protocol_binary_request_noop request= {.bytes= {0}}; - request.message.header.request.magic= PROTOCOL_BINARY_REQ; - request.message.header.request.opcode= PROTOCOL_BINARY_CMD_NOOP; - request.message.header.request.datatype= PROTOCOL_BINARY_RAW_BYTES; - - for (x= 0; x < ptr->number_of_hosts; x++) - if (memcached_server_response_count(&ptr->hosts[x])) - { - if (memcached_io_write(&ptr->hosts[x], request.bytes, - sizeof(request.bytes), 1) == -1) - { - memcached_io_reset(&ptr->hosts[x]); - dead_servers[x]= true; - success= false; - } - - /* mark all of the messages bound for this server as sent! */ - for (x= 0; x < number_of_keys; ++x) - if (hash[x] == x) - hash[x]= ptr->number_of_hosts; - } + memcached_server_response_increment(&ptr->hosts[server]); + hash[x]= ptr->number_of_hosts; } if (success) @@ -511,17 +517,19 @@ static memcached_return replication_binary_mget(memcached_st *ptr, static memcached_return binary_mget_by_key(memcached_st *ptr, unsigned int master_server_key, bool is_master_key_set, - const char **keys, size_t *key_length, - size_t number_of_keys, bool mget_mode) + const char * const *keys, + const size_t *key_length, + size_t number_of_keys, + bool mget_mode) { memcached_return rc; - if (ptr->number_of_replicas == 0) + if (ptr->number_of_replicas == 0) { rc= simple_binary_mget(ptr, master_server_key, is_master_key_set, keys, key_length, number_of_keys, mget_mode); - } - else + } + else { uint32_t* hash; bool* dead_servers; @@ -543,8 +551,8 @@ static memcached_return binary_mget_by_key(memcached_st *ptr, for (unsigned int x= 0; x < number_of_keys; x++) hash[x]= memcached_generate_hash(ptr, keys[x], key_length[x]); - rc= replication_binary_mget(ptr, hash, dead_servers, keys, - key_length, number_of_keys, mget_mode); + rc= replication_binary_mget(ptr, hash, dead_servers, keys, + key_length, number_of_keys); ptr->call_free(ptr, hash); ptr->call_free(ptr, dead_servers);