View Source depcache (depcache v2.0.1)
Depcache API
depcache API
flush/1, flush/2, get/2, get/3, get_subkey/3, get_wait/2, set/3, set/4, set/5, size/1memo/2, memo/3, memo/4, memo/5flush_process_dict/0, in_process/1, in_process_server/1
Internal
Summary
Functions
Cleanup process for the depcache. Periodically checks a batch of depcache items for their validity. Asks the depcache server to delete invalidated items. When the load of the data table is too high then This cleanup process starts to delete random entries. By using a random delete we don't need to keep a LRU list, which is a bit expensive.
Flush all keys from the caches
Flush the key and all keys depending on that key
Flush all items memoized in the process dictionary.
Fetch the key from the cache, return the data or an undefined if not found (or not valid).
Fetch the key from the cache, return the data or an undefined if not found (or not valid)
Fetch the key from the cache, return the data or an undefined if not found (or not valid)
Fetch the key from the cache, when the key does not exist then lock the entry and let the calling process insert the value. All other processes requesting the key will wait till the key is updated and receive the key's new value.
Enable or disable the in-process caching using the process dictionary
Check if we use a local process dict cache.
Cache the result of the function for an hour.
If Fun is a function then cache for an hour given the key. If Fun is a {M,F,A} tuple then derive the key from the tuple and cache for MaxAge seconds.
Equivalent to memo(Fun, Key, MaxAge, [], Server).
Cache the result of the function as Key for MaxAge seconds, flush the cached result if any of the dependencies is changed.
Equivalent to set(Key, Data, 3600, [], Server).
Equivalent to set(Key, Data, MaxAge, [], Server).
Add the key to the depcache, hold it for MaxAge seconds and check the dependencies.
Return the total memory size of all stored terms
Start a depcache process.
See also:gen_server:start_link/3.
Start a named depcache process.
See also:gen_server:start_link/4.
Types
-type callback() :: mfargs().
-type cleanup_state() :: #cleanup_state{pid :: pid(), tables :: tables(), name :: atom(), memory_max :: non_neg_integer(), callback :: callback() | undefined}.
-type config() :: config_map() | config_proplist().
-type config_map() :: #{memory_max => non_neg_integer() | undefined, callback => callback() | undefined}.
-type config_proplist() :: [{memory_max, non_neg_integer | undefined} | {callback, callback() | undefined}].
-type depend() :: #depend{key :: key(), serial :: non_neg_integer()}.
-type dependencies() :: [key()].
-type key() :: any().
-type max_age_secs() :: sec().
-type meta() :: #meta{key :: key(), expire :: sec(), serial :: non_neg_integer(), depend :: dependencies()}.
-type proplist() :: proplists:proplist().
-type sec() :: non_neg_integer().
-type state() :: #state{now :: sec(), serial :: non_neg_integer(), tables :: tables(), wait_pids :: map(), writers :: map()}.
Functions
-spec cleanup(CleanUp_state) -> Result when CleanUp_state :: cleanup_state(), Result :: no_return().
Equivalent to cleanup(CleanUp_state, SlotNr, Now, Mode, Ct).
Cleanup process for the depcache. Periodically checks a batch of depcache items for their validity. Asks the depcache server to delete invalidated items. When the load of the data table is too high then This cleanup process starts to delete random entries. By using a random delete we don't need to keep a LRU list, which is a bit expensive.
-spec cleanup(State, SlotNr, Now, Mode, Ct) -> Result when State :: cleanup_state(), SlotNr :: '$end_of_table' | non_neg_integer(), Now :: sec(), Mode :: normal | cache_full, Ct :: integer(), Result :: no_return().
Cleanup process for the depcache. Periodically checks a batch of depcache items for their validity. Asks the depcache server to delete invalidated items. When the load of the data table is too high then This cleanup process starts to delete random entries. By using a random delete we don't need to keep a LRU list, which is a bit expensive.
-spec flush(Server) -> Result when Server :: depcache_server(), Result :: ok.
Flush all keys from the caches
See also:gen_server:call/2.
-spec flush(Key, Server) -> Result when Key :: key(), Server :: depcache_server(), Result :: ok.
Flush the key and all keys depending on that key
See also:gen_server:call/2.
-spec flush_process_dict() -> Result when Result :: ok.
Flush all items memoized in the process dictionary.
-spec get(Key, Server) -> Result when Key :: key(), Server :: depcache_server(), Result :: {ok, any()} | undefined.
Fetch the key from the cache, return the data or an undefined if not found (or not valid).
See also:gen_server:call/2.
-spec get(Key, SubKey, Server) -> Result when Key :: key(), SubKey :: key(), Server :: depcache_server(), Result :: {ok, any()} | undefined.
Fetch the key from the cache, return the data or an undefined if not found (or not valid)
See also:gen_server:call/2.
-spec get_subkey(Key, SubKey, Server) -> Result when Key :: key(), SubKey :: key(), Server :: depcache_server(), Result :: {ok, any()} | undefined.
Fetch the key from the cache, return the data or an undefined if not found (or not valid)
See also:gen_server:call/2.
-spec get_wait(Key, Server) -> Result when Key :: key(), Server :: depcache_server(), Result :: {ok, any()} | undefined | {throw, term()} | {error, premature_exit}.
Fetch the key from the cache, when the key does not exist then lock the entry and let the calling process insert the value. All other processes requesting the key will wait till the key is updated and receive the key's new value.
See also:gen_server:call/3.
-spec in_process(IsChaching) -> Result when IsChaching :: undefined | boolean(), Result :: undefined | boolean().
Enable or disable the in-process caching using the process dictionary
-spec in_process_server(Server) -> Result when Server :: depcache_server(), Result :: boolean().
Check if we use a local process dict cache.
-spec memo(Fun, Server) -> Result when Fun :: memo_fun(), Server :: depcache_server(), Result :: any().
Cache the result of the function for an hour.
-spec memo(Fun, MaxAge_Key, Server) -> Result when Fun :: memo_fun(), MaxAge_Key :: MaxAge | Key, MaxAge :: max_age_secs(), Key :: key(), Server :: depcache_server(), Result :: any().
If Fun is a function then cache for an hour given the key. If Fun is a {M,F,A} tuple then derive the key from the tuple and cache for MaxAge seconds.
-spec memo(Fun, Key, MaxAge, Server) -> Result when Fun :: memo_fun(), Key :: key(), MaxAge :: max_age_secs(), Server :: depcache_server(), Result :: any().
Equivalent to memo(Fun, Key, MaxAge, [], Server).
Cache the result of the function as Key for MaxAge seconds.
-spec memo(Fun, Key, MaxAge, Dep, Server) -> Result when Fun :: memo_fun(), Key :: undefined | key(), MaxAge :: max_age_secs(), Dep :: dependencies(), Server :: depcache_server(), Result :: any().
Cache the result of the function as Key for MaxAge seconds, flush the cached result if any of the dependencies is changed.
-spec set(Key, Data, Server) -> Result when Key :: key(), Data :: any(), Server :: depcache_server(), Result :: ok.
Equivalent to set(Key, Data, 3600, [], Server).
Add the key to the depcache, hold it for 3600 seconds and no dependencies.
-spec set(Key, Data, MaxAge, Server) -> Result when Key :: key(), Data :: any(), MaxAge :: max_age_secs(), Server :: depcache_server(), Result :: ok.
Equivalent to set(Key, Data, MaxAge, [], Server).
Add the key to the depcache, hold it for MaxAge seconds and no dependencies.
-spec set(Key, Data, MaxAge, Depend, Server) -> Result when Key :: key(), Data :: any(), MaxAge :: max_age_secs(), Depend :: dependencies(), Server :: depcache_server(), Result :: ok.
Add the key to the depcache, hold it for MaxAge seconds and check the dependencies.
-spec size(Server) -> Result when Server :: depcache_server(), Result :: non_neg_integer() | undefined.
Return the total memory size of all stored terms
-spec start_link(Config) -> Result when Config :: config(), Result :: {ok, pid()} | ignore | {error, term()}.
Start a depcache process.
See also:gen_server:start_link/3.
For Config, you can pass:
callback => {Module, Function, Arguments}- depcache event callback
memory_max => MaxMemoryInMB- number of MB to limit depcache size at
-spec start_link(Name, Config) -> Result when Name :: atom(), Config :: config(), Result :: {ok, pid()} | ignore | {error, term()}.
Start a named depcache process.
See also:gen_server:start_link/4.
For Config, you can pass:
callback => {Module, Function, Arguments}- depcache event callback
memory_max => MaxMemoryInMB- number of MB to limit depcache size at