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MemoryImplementation.Vm-max-threads 4############################## ADVANCED CONFIG################################ When the hash contains more than the specified number of elements and the maximum number of elements does not exceed the critical value,#Hash will be stored in a special encoding method (greatly reducing memory usage). Here we can set these two thresholds.# RedisThe Value corresponding to the Hash is actually a HashMap, which has two different implementations,#When there are few M
blocking # Virtual Memory implementation. # Set the number of threads simultaneously used by vm io. Vm-max-threads 4 # Hashes are encoded in a special way (much more memory efficient) when they # Have at max a given numer of elements, and the biggest element does not # Exceed a given threshold. You can configure this limits with the following # Configuration ctictives. # The hash data structure is introduced in redis 2.0. # When the hash contains more than the specified number of elements and
corresponds to value inside is actually a hashmap, actually there will be 2 different implementations,# This hash of the members relatively young Redis in order to save memory will be similar to a one-dimensional array of compact storage, without the use of real hashmap structure, the corresponding value Redisobject encoding is Zipmap,# when the number of members increases, it automatically turns into a real hashmap, at which time encoding is HT.Hash
logging, and setting to 0 will force each command to be logged; -) hash-max-zipmap-entries + Hash-max-zipmap-value -When a hash contains more than the specified number of elements and the largest element does not exceed the critical value, the hash will be stored in a special encoding method (greatly reducing memory usage), where these two thresholds can be set. Redis hash corresponds to value inside is ac
capacity estimates in the article, with two minor flaws: 1. For the storage of value, the estimated 16 bytes in this article, in fact, this part of the cost can be saved. The Createstringobjectfromlonglong function does not allocate additional space for value values that are less than redis_shared_integers. Redis_shared_integers default is 10000, larger to meet the majority of demand //@ Liu Hao Bupt: @cydu 2. Is the memory utilization that can be evaluated under use
memory will be similar to a one-dimensional array of compact storage, without the use of real HASHMAP structure, the corresponding Valueredisobject encoding is ZIPMAP,# when the number of members increases, it automatically turns into a real HashMap, at which time encoding is HT. Hash-max-zipmap-entries512hash-max-zipmap-Value64# As with Hash, multiple small lis
is relatively young redis in order to save memory will be similar to a one-dimensional array of compact storage, rather than the real hashmap structure, the corresponding valueThe encoding of Redisobject is Zipmap,#When the number of members increases, it automatically turns into a true hashmap, at which point encoding is HT.Hash-max-zipmap-entries512Hash-max-zipmap
off threaded I/O and enables the blocking# Virtual Memory implementation.#设置 the number of threads used concurrently with VM IO.Vm-max-threads 4 # hashes is encoded in a special to (much more memory efficient) when they# has at Max a given numer of elements, and the biggest element does not# exceed a given threshold. Can configure this limits with the following# Configuration directives.A hash data structure was introduced in #redis 2.0.#hash contains more than the specified number of elements
directly through its internal map key (Redis called internal map key field), that is, through the Key (User ID) + field (attribute tag) can manipulate the corresponding attribute data, neither need to store data repeatedly, nor bring serialization and deserialization Client.Setentryinhash ("user", "UserInfo", "aaaaaaaaaa"); liststring> list = client.Gethashkeys ("user"); liststring> list = client. Gethashvalues ("UserInfo"); Get value liststring> list = client. Getallk
linear compact format. The default value is 64. That is, if the value contains less than 64 members, it uses linear compact storage, if this value is exceeded, it is automatically converted to a real HashMap.Hhash-max-zipmap-entries 512# When the length of each member value in the Map is no more than a few bytes, the linear compact storage is used to save space.Hash-max-zipmap-value 64# Similar to the hash
data repeatedly, nor bring serialization and deserialization[CSharp]View Plaincopy Client.Setentryinhash ("user", "UserInfo", "aaaaaaaaaa"); liststring> list = client.Gethashkeys ("user"); liststring> list = client. Gethashvalues ("UserInfo"); Get value liststring> list = client. Getallkeys ();//Get all the keys. Redis provides a set of parameters for different data types to control memory usage, and the value inside of the Redis hash we mentioned earlier is aHas
data repeatedly, nor bring serialization and deserialization[CSharp]View Plaincopy Client.Setentryinhash ("user", "UserInfo", "aaaaaaaaaa"); liststring> list = client.Gethashkeys ("user"); liststring> list = client. Gethashvalues ("UserInfo"); Get value liststring> list = client. Getallkeys ();//Get all the keys. Redis provides a set of parameters for different data types to control memory usage, and the value inside of the Redis hash we mentioned earlier is aHas
effectively protect your Redis against swap caused by excessive physical memory usage, which seriously affects performance and even crashes.In addition, Redis provides a set of parameters for different data types to control memory usage. We know that RedisHash is a HashMap inside the value. If the number of members of this Map is small, A compact format similar to one-dimensional linear format is used to store the Map, which saves the memory overhead of a large number of pointers. this paramete
is relatively young redis in order to save memory will be similar to a one-dimensional array of compact storage, rather than the real hashmap structure, the corresponding valueThe encoding of Redisobject is Zipmap,#When the number of members increases, it automatically turns into a true hashmap, at which point encoding is HT.Hash-max-zipmap-entries512Hash-max-zipmap
the blocking# Virtual Memory implementation.#设置 the number of threads used concurrently with VM IO.Vm-max-threads 4# hashes is encoded in a special to (much more memory efficient) when they# has at Max a given numer of elements, and the biggest element does not# exceed a given threshold. Can configure this limits with the following# Configuration directives.A hash data structure was introduced in #redis 2.0.#hash contains more than the specified number of elements and the largest element when n
, actually there will be 2 different implementations,# This Hash of the members relatively young Redis in order to save memory will be similar to a one-dimensional array of compact storage, without the use of real HASHMAP structure, the corresponding Valueredisobject encoding is ZIPMAP,# when the number of members increases, it automatically turns into a real HashMap, at which time encoding is HT.Hash-max-zipmap
contains more than the specified number of elements and the largest element does not exceed the critical,# hash will be stored in a special coding way (greatly reduced memory usage), where you can set both thresholds# Redis Hash corresponds to Value inside is actually a HashMap, actually there will be 2 different implementations,# This Hash of the members relatively young Redis in order to save memory will be similar to a one-dimensional array of compact storage, without the use of real HASHMAP
string Encoding". Value, using "Redis value Encoding" to make different storage based on different data types Key Expiration TimeThe expiration time is used at the beginning of the 0xFD or 0xFC for identification, indicating the second-level expiration and the millisecond-level expiration time, followed by a Unix timestamp, seconds, or milliseconds. The value of the timestamp is stored by the "Redis Length Encoding" encoding. During the import of an rdb file, the expiration time is det
even crashing.In addition, Redis provides a set of parameters for different data types to control memory usage, and we know that Redis hash is a hashmap within value, and if the map has a smaller number of members, it will be stored in a compact format similar to one-dimensional linear, This eliminates the memory overhead of a large number of pointers, and this parameter controls the following 2 entries in the redis.conf configuration file:Hash-max-zipmap
be stored in a special encoding (greatly reduced memory usage), where these two thresholds can be set# RedisHash corresponds to value inside is actually a hashmap, actually there will be 2 different implementations,#This hash of the members is relatively young redis in order to save memory will be similar to a one-dimensional array of compact storage, rather than the real hashmap structure, the corresponding valueThe encoding of Redisobject is Zipmap
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