X-Git-Url: https://git.m6w6.name/?a=blobdiff_plain;f=libmemcached%2Fmemcached_hash.c;h=e6747db5f7b2de3ba64ae67a658c9e25a60ebba6;hb=20b4431225d4ccd4aa22f6d7f67476c92d1c9546;hp=cca7b5a40ab7e3ec3c6457a7cc0dda4e6c5fbafa;hpb=571fad579922f2b10873193500dfd0652f4fdc37;p=awesomized%2Flibmemcached diff --git a/libmemcached/memcached_hash.c b/libmemcached/memcached_hash.c index cca7b5a4..e6747db5 100644 --- a/libmemcached/memcached_hash.c +++ b/libmemcached/memcached_hash.c @@ -1,5 +1,6 @@ #include "common.h" + /* Defines */ static uint64_t FNV_64_INIT= 0xcbf29ce484222325LL; static uint64_t FNV_64_PRIME= 0x100000001b3LL; @@ -11,18 +12,12 @@ static uint32_t FNV_32_PRIME= 16777619; static uint32_t internal_generate_hash(const char *key, size_t key_length); static uint32_t internal_generate_md5(const char *key, size_t key_length); -uint32_t generate_hash(memcached_st *ptr, const char *key, size_t key_length) +uint32_t memcached_generate_hash_value(const char *key, size_t key_length, memcached_hash hash_algorithm) { uint32_t hash= 1; /* Just here to remove compile warning */ uint32_t x= 0; - - WATCHPOINT_ASSERT(ptr->number_of_hosts); - - if (ptr->number_of_hosts == 1) - return 0; - - switch (ptr->hash) + switch (hash_algorithm) { case MEMCACHED_HASH_DEFAULT: hash= internal_generate_hash(key, key_length); @@ -82,7 +77,9 @@ uint32_t generate_hash(memcached_st *ptr, const char *key, size_t key_length) break; case MEMCACHED_HASH_HSIEH: { +#ifdef HAVE_HSIEH_HASH hash= hsieh_hash(key, key_length); +#endif break; } case MEMCACHED_HASH_MURMUR: @@ -90,71 +87,68 @@ uint32_t generate_hash(memcached_st *ptr, const char *key, size_t key_length) hash= murmur_hash(key, key_length); break; } + case MEMCACHED_HASH_JENKINS: + { + hash=jenkins_hash(key, key_length, 13); + break; + } } + return hash; +} + +uint32_t generate_hash(memcached_st *ptr, const char *key, size_t key_length) +{ + uint32_t hash= 1; /* Just here to remove compile warning */ + + + WATCHPOINT_ASSERT(ptr->number_of_hosts); + + if (ptr->number_of_hosts == 1) + return 0; + hash= memcached_generate_hash_value(key, key_length, ptr->hash); WATCHPOINT_ASSERT(hash); return hash; } -unsigned int dispatch_host(memcached_st *ptr, uint32_t hash) +static uint32_t dispatch_host(memcached_st *ptr, uint32_t hash) { switch (ptr->distribution) { case MEMCACHED_DISTRIBUTION_CONSISTENT: case MEMCACHED_DISTRIBUTION_CONSISTENT_KETAMA: { - uint32_t num= ptr->number_of_hosts * MEMCACHED_POINTS_PER_SERVER; + uint32_t num= ptr->continuum_points_counter; WATCHPOINT_ASSERT(ptr->continuum); hash= hash; memcached_continuum_item_st *begin, *end, *left, *right, *middle; begin= left= ptr->continuum; - end= right= ptr->continuum + (num - 1); + end= right= ptr->continuum + num; - while (1) + while (left < right) { - memcached_continuum_item_st *rmiddle; - - middle = left + (right - left) / 2; - - if (middle==end) - return begin->index; - - if (middle==begin) - return end->index; - - rmiddle = middle+1; - - if (hashvalue && hash>=middle->value) - return middle->index; - + middle= left + (right - left) / 2; if (middle->value < hash) - left = middle + 1; - else if (middle->value > hash) - right = middle - 1; - - if (left>right) - return left->index; + left= middle + 1; + else + right= middle; } + if (right == end) + right= begin; + return right->index; } break; - case MEMCACHED_DISTRIBUTION_CONSISTENT_WHEEL: - { - unsigned int server_key; - - server_key= hash % MEMCACHED_STRIDE * ptr->wheel_count; - - return ptr->wheel[server_key]; - } case MEMCACHED_DISTRIBUTION_MODULA: return hash % ptr->number_of_hosts; + case MEMCACHED_DISTRIBUTION_RANDOM: + return random() % ptr->number_of_hosts; default: WATCHPOINT_ASSERT(0); /* We have added a distribution without extending the logic */ return hash % ptr->number_of_hosts; } - WATCHPOINT_ASSERT(0); /* We should never reach here */ - return 0; + /* NOTREACHED */ } /* @@ -170,9 +164,30 @@ uint32_t memcached_generate_hash(memcached_st *ptr, const char *key, size_t key_ if (ptr->number_of_hosts == 1) return 0; - hash = generate_hash(ptr, key, key_length); + if (ptr->flags & MEM_HASH_WITH_PREFIX_KEY) + { + int temp_len= ptr->prefix_key_length + key_length; + char *temp= (char *)malloc(temp_len); + strncpy(temp, ptr->prefix_key, ptr->prefix_key_length); + strncpy(temp + ptr->prefix_key_length, key, key_length); + hash= generate_hash(ptr, temp, temp_len); + free(temp); + } + else + { + hash= generate_hash(ptr, key, key_length); + } WATCHPOINT_ASSERT(hash); + + if (memcached_behavior_get(ptr, MEMCACHED_BEHAVIOR_AUTO_EJECT_HOSTS) && ptr->next_distribution_rebuild) { + struct timeval now; + + if (gettimeofday(&now, NULL) == 0 && + now.tv_sec > ptr->next_distribution_rebuild) + run_distribution(ptr); + } + return dispatch_host(ptr, hash); } @@ -181,7 +196,7 @@ static uint32_t internal_generate_hash(const char *key, size_t key_length) const char *ptr= key; uint32_t value= 0; - while (--key_length) + while (key_length--) { value += *ptr++; value += (value << 10);