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release 0.8.0 - re-factored cache bucket structure. The application uses segmented cache approach vs B-tree index for TTL handling
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20
Makefile
20
Makefile
@ -1,5 +1,17 @@
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.PHONY: deps test
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ifeq ($(id),)
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export id=cache
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endif
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FLAGS=\
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-name ${id}@127.0.0.1 \
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-setcookie nocookie \
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-pa ./deps/*/ebin \
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-pa ./examples/*/ebin \
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-pa ./ebin \
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+K true +A 160 -sbt ts
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BB=../basho_bench
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|
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all: rebar deps compile
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@ -27,15 +39,19 @@ dialyzer: compile
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@dialyzer -Wno_return -c ./ebin
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run:
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erl -name cache@127.0.0.1 -setcookie nocookie -pa ./deps/*/ebin -pa ./ebin
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erl ${FLAGS}
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rebar:
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curl -O http://cloud.github.com/downloads/basho/rebar/rebar
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chmod ugo+x rebar
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||||
|
||||
benchmark:
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$(BB)/basho_bench priv/cache.benchmark
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||||
$(BB)/basho_bench -N bb@127.0.0.0 -C nocookie -J ${id}@127.0.0.1 priv/${id}.benchmark
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||||
$(BB)/priv/summary.r -i tests/current
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open tests/current/summary.png
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||||
|
||||
# benchmark:
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||||
# $(BB)/basho_bench -N bb@127.0.0.0 -C nocookie -J ${id}@127.0.0.1 priv/${id}.benchmark
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||||
# $(BB)/priv/summary.r -i tests/current
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||||
# open tests/current/summary.png
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|
80
README.md
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80
README.md
Normal file
@ -0,0 +1,80 @@
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# Segmented in-memory cache
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Cache uses N disposable ETS tables instead of single one. The cache applies eviction and quota
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policies at segment level. The oldest ETS table is destroyed and new one is created when
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quota or TTL criteria are exceeded.
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The write operation always uses youngest segment. The read operation lookup key from youngest to oldest table
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until it is found same time key is moved to youngest segment to prolong TTL. If none of ETS table contains key
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then cache-miss occurs.
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The downside is inability to assign precise TTL per single cache entry. TTL is always approximated to nearest segment. (e.g. cache with 60 sec TTL and 10 segments has 6 sec accuracy on TTL)
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|
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|
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## Usage
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|
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```erlang
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application:start(cache).
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{ok, _} = cache:start_link(my_cache, [{n, 10}, {ttl, 60}]).
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|
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ok = cache:put(my_cache, <<"my key">>, <<"my value">>).
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Val = cache:get(my_cache, <<"my key">>).
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```
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### configuration via Erlang `sys.config`
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|
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The cache instances are configurable via `sys.config`. Theses cache instances are supervised by application
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supervisor.
|
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|
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```erlang
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{cache, [
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{my_cache, [{n, 10}, {ttl, 60}]}
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]}
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```
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### distributed environment
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The cache application uses standard Erlang distribution model.
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Please node that Erlang distribution uses single tcp/ip connection for message passing between nodes.
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Therefore, frequent read/write of large entries might impact on overall Erlang performance.
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|
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The global cache instance is visible to all Erlang nodes in the cluster.
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||||
```erlang
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%% at a@example.com
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{ok, _} = cache:start_link({global, my_cache}, [{n, 10}, {ttl, 60}]).
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Val = cache:get({global, my_cache}, <<"my key">>).
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|
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%% at b@example.com
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ok = cache:put({global, my_cache}, <<"my key">>, <<"my value">>).
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Val = cache:get({global, my_cache}, <<"my key">>).
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```
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|
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The local cache instance is accessible for any Erlang nodes in the cluster.
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|
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```erlang
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%% a@example.com
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{ok, _} = cache:start_link(my_cache, [{n, 10}, {ttl, 60}]).
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Val = cache:get(my_cache, <<"my key">>).
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%% b@example.com
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ok = cache:put({my_cache, 'a@example.com'}, <<"my key">>, <<"my value">>).
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Val = cache:get({my_cache, 'a@example.com'}, <<"my key">>).
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```
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|
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## Performance
|
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MacBook Pro, Intel Core i5, 2.5GHz, 8GB 1600 MHz DDR3, 256 SSD
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LRU Cache, 10 segments, 20 sec ttl (~2 sec per segment)
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|
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![Local cache (application and cache within same VM)](local.png)
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![Distributed cache (application and cache runs in different VMs)](distributed.png)
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## Contributors
|
||||
* Jose Luis Navarro https://github.com/artefactop
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||||
* Valentin Micic
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|
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|
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|
BIN
distributed.png
Normal file
BIN
distributed.png
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Binary file not shown.
After Width: | Height: | Size: 100 KiB |
@ -6,7 +6,7 @@
|
||||
%%
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||||
%% workload
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{mode, max}.
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{duration, 1}.
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{duration, 5}.
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{concurrent, 10}.
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||||
{key_generator, {uniform_int, 1000000}}.
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{value_generator, {fixed_bin, 1000}}.
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||||
@ -14,7 +14,6 @@
|
||||
{operations, [
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||||
{put, 5}
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,{get, 5}
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%,{remove, 1}
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||||
]}.
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%{cache, {mycache, 'cache@127.0.0.1'}}.
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||||
@ -22,6 +21,4 @@
|
||||
{ttl, 20}
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||||
,{n, 10}
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,{policy, lru}
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||||
%,{size, 500000}
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||||
%,{memory, 400000000}
|
||||
]}.
|
||||
|
@ -1,9 +1,10 @@
|
||||
{application, cache,
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||||
[
|
||||
{description, "in-memory cache"},
|
||||
{vsn, "0.3.0"},
|
||||
{vsn, "0.8.0"},
|
||||
{modules, [
|
||||
cache,
|
||||
cache_bucket,
|
||||
cache_sup,
|
||||
cache_app
|
||||
]},
|
||||
|
122
src/cache.erl
122
src/cache.erl
@ -1,32 +1,41 @@
|
||||
%%
|
||||
%% Copyright (c) 2012, Dmitry Kolesnikov
|
||||
%% All Rights Reserved.
|
||||
%% Copyright 2012 Dmitry Kolesnikov, All Rights Reserved
|
||||
%%
|
||||
%% This library is free software; you can redistribute it and/or modify
|
||||
%% it under the terms of the GNU Lesser General Public License, version 3.0
|
||||
%% as published by the Free Software Foundation (the "License").
|
||||
%% Licensed under the Apache License, Version 2.0 (the "License");
|
||||
%% you may not use this file except in compliance with the License.
|
||||
%% You may obtain a copy of the License at
|
||||
%%
|
||||
%% Software distributed under the License is distributed on an "AS IS"
|
||||
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
|
||||
%% the License for the specific language governing rights and limitations
|
||||
%% under the License.
|
||||
%% http://www.apache.org/licenses/LICENSE-2.0
|
||||
%%
|
||||
%% You should have received a copy of the GNU Lesser General Public
|
||||
%% License along with this library; if not, write to the Free Software
|
||||
%% Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
|
||||
%% USA or retrieve online http://www.opensource.org/licenses/lgpl-3.0.html
|
||||
%% Unless required by applicable law or agreed to in writing, software
|
||||
%% distributed under the License is distributed on an "AS IS" BASIS,
|
||||
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
%% See the License for the specific language governing permissions and
|
||||
%% limitations under the License.
|
||||
%%
|
||||
%% @description
|
||||
%% segmented in-memory cache, cache memory is split into N segments,
|
||||
%% each segment is associated with quota and ttl, eviction policy applied
|
||||
%% at segment level.
|
||||
%% segmented in-memory cache
|
||||
%% * cache memory is split into N segments
|
||||
%% * cache applies eviction and quota policies at segment level
|
||||
%% (e.g. whole segments is destroyed at time)
|
||||
%% * cache add new items to youngest segment
|
||||
%% * cache lookup items from youngest to oldest segment
|
||||
%%
|
||||
%% @todo
|
||||
%% * unit tests (improve coverage)
|
||||
%% * cache read/write through handler
|
||||
%% * cache atomic update (in-place update)
|
||||
%% * memcached protocol
|
||||
-module(cache).
|
||||
-author('Dmitry Kolesnikov <dmkolesnikov@gmail.com>').
|
||||
|
||||
-include("cache.hrl").
|
||||
|
||||
-export([
|
||||
start_link/2,
|
||||
drop/1,
|
||||
i/1,
|
||||
i/2,
|
||||
heap/2,
|
||||
put/3,
|
||||
put/4,
|
||||
@ -40,45 +49,72 @@
|
||||
remove_/2
|
||||
]).
|
||||
|
||||
-export_type([cache/0]).
|
||||
|
||||
-type(cache() :: atom() | {atom(), atom()} | {global, atom()} | pid()).
|
||||
-type(name() :: atom() | {global, atom()}).
|
||||
-type(key() :: any()).
|
||||
-type(entity() :: any()).
|
||||
-type(ttl() :: integer()).
|
||||
|
||||
%%
|
||||
%% start new cache
|
||||
-spec(start_link/2 :: (atom(), list()) -> {ok, pid()} | {error, any()}).
|
||||
%% start new cache bucket, accepted options:
|
||||
%% {policy, lru | mru} - cache eviction policy
|
||||
%% {memory, integer()} - cache memory quota in bytes
|
||||
%% {size, integer()} - cache cardinality quota
|
||||
%% {n, integer()} - number of cache segments
|
||||
%% {ttl, integer()} - default time-to-live in seconds
|
||||
%% {quota, integer()} - frequency of quota check in seconds
|
||||
%% {stats, function() | {Mod, Fun}} - cache statistic aggregate functor
|
||||
-spec(start_link/2 :: (name(), list()) -> {ok, pid()} | {error, any()}).
|
||||
|
||||
start_link(Cache, Opts) ->
|
||||
cache_bucket:start_link(Cache, Opts).
|
||||
|
||||
%%
|
||||
%% drop cache
|
||||
-spec(drop/1 :: (atom()) -> ok).
|
||||
-spec(drop/1 :: (cache()) -> ok).
|
||||
|
||||
drop(Cache) ->
|
||||
erlang:exit(whereis(Cache), shutdown).
|
||||
drop(undefined) ->
|
||||
ok;
|
||||
drop({global, Cache}) ->
|
||||
drop(global:whereis_name(Cache));
|
||||
drop({Cache, Node}) ->
|
||||
drop(rpc:call(Node, cache, drop, [Cache]));
|
||||
drop(Cache)
|
||||
when is_atom(Cache) ->
|
||||
drop(whereis(Cache));
|
||||
drop(Cache)
|
||||
when is_pid(Cache) ->
|
||||
erlang:exit(Cache, shutdown).
|
||||
|
||||
%%
|
||||
%% return cache meta data
|
||||
-spec(i/1 :: (atom()) -> list()).
|
||||
%% {heap, [integer()]} - cache segments references
|
||||
%% {expire, [integer()]} - cache segments expire times
|
||||
%% {size, [integer()]} - cardinality of cache segments
|
||||
%% {memory, [integer()]} - memory occupied by each cache segment
|
||||
-spec(i/1 :: (cache()) -> list()).
|
||||
-spec(i/2 :: (cache(), atom()) -> list()).
|
||||
|
||||
i(Cache) ->
|
||||
gen_server:call(Cache, i).
|
||||
|
||||
i(Cache, Name) ->
|
||||
proplists:get_value(Name, i(Cache)).
|
||||
|
||||
%%
|
||||
%% return nth cache heap
|
||||
-spec(heap/2 :: (atom(), integer()) -> integer() | badarg).
|
||||
%% return nth cache segment (e.g. heap(..., 1) returns youngest segment)
|
||||
-spec(heap/2 :: (cache(), integer()) -> integer() | badarg).
|
||||
|
||||
heap(Cache, N) ->
|
||||
gen_server:call(Cache, {heap, N}).
|
||||
|
||||
|
||||
%%
|
||||
%% put entity to cache
|
||||
-spec(put/3 :: (atom(), key(), entity()) -> ok).
|
||||
-spec(put_/3 :: (atom(), key(), entity()) -> ok).
|
||||
-spec(put/4 :: (atom(), key(), entity(), ttl()) -> ok).
|
||||
-spec(put_/4 :: (atom(), key(), entity(), ttl()) -> ok).
|
||||
%% synchronous cache put
|
||||
-spec(put/3 :: (cache(), key(), entity()) -> ok).
|
||||
-spec(put/4 :: (cache(), key(), entity(), ttl()) -> ok).
|
||||
|
||||
put(Cache, Key, Val) ->
|
||||
gen_server:call(Cache, {put, Key, Val}, ?DEF_CACHE_TIMEOUT).
|
||||
@ -86,6 +122,11 @@ put(Cache, Key, Val) ->
|
||||
put(Cache, Key, Val, TTL) ->
|
||||
gen_server:call(Cache, {put, Key, Val, TTL}, ?DEF_CACHE_TIMEOUT).
|
||||
|
||||
%%
|
||||
%% asynchronous cache put
|
||||
-spec(put_/3 :: (cache(), key(), entity()) -> ok).
|
||||
-spec(put_/4 :: (cache(), key(), entity(), ttl()) -> ok).
|
||||
|
||||
put_(Cache, Key, Val) ->
|
||||
gen_server:cast(Cache, {put, Key, Val}).
|
||||
|
||||
@ -93,41 +134,44 @@ put_(Cache, Key, Val, TTL) ->
|
||||
gen_server:cast(Cache, {put, Key, Val, TTL}).
|
||||
|
||||
%%
|
||||
%% get entity from cache, prolong ttl
|
||||
-spec(get/2 :: (atom(), key()) -> entity() | undefined).
|
||||
%% synchronous get cache entry, the operation prolongs entry ttl
|
||||
-spec(get/2 :: (cache(), key()) -> entity() | undefined).
|
||||
|
||||
get(Cache, Key) ->
|
||||
gen_server:call(Cache, {get, Key}, ?DEF_CACHE_TIMEOUT).
|
||||
|
||||
%%
|
||||
%% lookup entity at cache do not prolong ttl
|
||||
-spec(lookup/2 :: (atom(), key()) -> entity() | undefined).
|
||||
%% synchronous lookup cache entry, the operation do not prolong entry ttl
|
||||
-spec(lookup/2 :: (cache(), key()) -> entity() | undefined).
|
||||
|
||||
lookup(Cache, Key) ->
|
||||
gen_server:call(Cache, {lookup, Key}, ?DEF_CACHE_TIMEOUT).
|
||||
|
||||
%%
|
||||
%% check entity at cache
|
||||
-spec(has/2 :: (atom(), key()) -> true | false).
|
||||
%% check if cache key exists,
|
||||
-spec(has/2 :: (cache(), key()) -> true | false).
|
||||
|
||||
has(Cache, Key) ->
|
||||
gen_server:call(Cache, {has, Key}, ?DEF_CACHE_TIMEOUT).
|
||||
|
||||
%%
|
||||
%% check entity at cache and return estimated ttl
|
||||
-spec(ttl/2 :: (atom(), key()) -> ttl() | false).
|
||||
-spec(ttl/2 :: (cache(), key()) -> ttl() | false).
|
||||
|
||||
ttl(Cache, Key) ->
|
||||
gen_server:call(Cache, {ttl, Key}, ?DEF_CACHE_TIMEOUT).
|
||||
|
||||
%%
|
||||
%% remove entity from cache
|
||||
-spec(remove/2 :: (atom(), key()) -> ok).
|
||||
-spec(remove_/2 :: (atom(), key()) -> ok).
|
||||
%% synchronous remove entry from cache
|
||||
-spec(remove/2 :: (cache(), key()) -> ok).
|
||||
|
||||
remove(Cache, Key) ->
|
||||
gen_server:call(Cache, {remove, Key}, ?DEF_CACHE_TIMEOUT).
|
||||
|
||||
%%
|
||||
%% asynchronous remove entry from cache
|
||||
-spec(remove_/2 :: (cache(), key()) -> ok).
|
||||
|
||||
remove_(Cache, Key) ->
|
||||
gen_server:cast(Cache, {remove, Key}).
|
||||
|
||||
|
@ -1,4 +1,18 @@
|
||||
|
||||
%%
|
||||
%% Copyright 2012 Dmitry Kolesnikov, All Rights Reserved
|
||||
%%
|
||||
%% Licensed under the Apache License, Version 2.0 (the "License");
|
||||
%% you may not use this file except in compliance with the License.
|
||||
%% You may obtain a copy of the License at
|
||||
%%
|
||||
%% http://www.apache.org/licenses/LICENSE-2.0
|
||||
%%
|
||||
%% Unless required by applicable law or agreed to in writing, software
|
||||
%% distributed under the License is distributed on an "AS IS" BASIS,
|
||||
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
%% See the License for the specific language governing permissions and
|
||||
%% limitations under the License.
|
||||
%%
|
||||
|
||||
%-define(VERBOSE, true).
|
||||
-ifdef(VERBOSE).
|
||||
|
@ -1,22 +1,20 @@
|
||||
%%
|
||||
%% Copyright (c) 2012, Dmitry Kolesnikov
|
||||
%% All Rights Reserved.
|
||||
%% Copyright 2012 Dmitry Kolesnikov, All Rights Reserved
|
||||
%%
|
||||
%% This library is free software; you can redistribute it and/or modify
|
||||
%% it under the terms of the GNU Lesser General Public License, version 3.0
|
||||
%% as published by the Free Software Foundation (the "License").
|
||||
%% Licensed under the Apache License, Version 2.0 (the "License");
|
||||
%% you may not use this file except in compliance with the License.
|
||||
%% You may obtain a copy of the License at
|
||||
%%
|
||||
%% Software distributed under the License is distributed on an "AS IS"
|
||||
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
|
||||
%% the License for the specific language governing rights and limitations
|
||||
%% under the License.
|
||||
%% http://www.apache.org/licenses/LICENSE-2.0
|
||||
%%
|
||||
%% You should have received a copy of the GNU Lesser General Public
|
||||
%% License along with this library; if not, write to the Free Software
|
||||
%% Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
|
||||
%% USA or retrieve online http://www.opensource.org/licenses/lgpl-3.0.html
|
||||
%% Unless required by applicable law or agreed to in writing, software
|
||||
%% distributed under the License is distributed on an "AS IS" BASIS,
|
||||
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
%% See the License for the specific language governing permissions and
|
||||
%% limitations under the License.
|
||||
%%
|
||||
%% @description
|
||||
%% cache application
|
||||
-module(cache_app).
|
||||
-behaviour(application).
|
||||
-author('Dmitry Kolesnikov <dmkolesnikov@gmail.com>').
|
||||
|
@ -1,28 +1,24 @@
|
||||
%%
|
||||
%% Copyright (c) 2012, Dmitry Kolesnikov
|
||||
%% All Rights Reserved.
|
||||
%% Copyright 2012 Dmitry Kolesnikov, All Rights Reserved
|
||||
%%
|
||||
%% This library is free software; you can redistribute it and/or modify
|
||||
%% it under the terms of the GNU Lesser General Public License, version 3.0
|
||||
%% as published by the Free Software Foundation (the "License").
|
||||
%% Licensed under the Apache License, Version 2.0 (the "License");
|
||||
%% you may not use this file except in compliance with the License.
|
||||
%% You may obtain a copy of the License at
|
||||
%%
|
||||
%% Software distributed under the License is distributed on an "AS IS"
|
||||
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
|
||||
%% the License for the specific language governing rights and limitations
|
||||
%% under the License.
|
||||
%% http://www.apache.org/licenses/LICENSE-2.0
|
||||
%%
|
||||
%% You should have received a copy of the GNU Lesser General Public
|
||||
%% License along with this library; if not, write to the Free Software
|
||||
%% Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
|
||||
%% USA or retrieve online http://www.opensource.org/licenses/lgpl-3.0.html
|
||||
%% Unless required by applicable law or agreed to in writing, software
|
||||
%% distributed under the License is distributed on an "AS IS" BASIS,
|
||||
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
%% See the License for the specific language governing permissions and
|
||||
%% limitations under the License.
|
||||
%%
|
||||
%% @description
|
||||
%% basho_bench driver
|
||||
%% @description
|
||||
%% cache basho_bench driver
|
||||
-module(cache_benchmark).
|
||||
-author('Dmitry Kolesnikov <dmkolesnikov@gmail.com>').
|
||||
|
||||
-export([
|
||||
new/1, run/4
|
||||
]).
|
||||
-export([new/1, run/4]).
|
||||
|
||||
%%
|
||||
%%
|
||||
@ -76,7 +72,6 @@ local_init() ->
|
||||
|
||||
%%
|
||||
%%
|
||||
failure(Tag, _Key, E) ->
|
||||
%io:format("----> ~p~n", [process_info(pns:whereis(kv, Key))]),
|
||||
io:format("~s -> ~p~n", [Tag, E]),
|
||||
failure(_Tag, _Key, _E) ->
|
||||
%io:format("~s -> ~p~n", [Tag, E]),
|
||||
failed.
|
||||
|
@ -1,52 +1,55 @@
|
||||
%%
|
||||
%% Copyright (c) 2012, Dmitry Kolesnikov
|
||||
%% All Rights Reserved.
|
||||
%% Copyright 2012 Dmitry Kolesnikov, All Rights Reserved
|
||||
%%
|
||||
%% This library is free software; you can redistribute it and/or modify
|
||||
%% it under the terms of the GNU Lesser General Public License, version 3.0
|
||||
%% as published by the Free Software Foundation (the "License").
|
||||
%% Licensed under the Apache License, Version 2.0 (the "License");
|
||||
%% you may not use this file except in compliance with the License.
|
||||
%% You may obtain a copy of the License at
|
||||
%%
|
||||
%% Software distributed under the License is distributed on an "AS IS"
|
||||
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
|
||||
%% the License for the specific language governing rights and limitations
|
||||
%% under the License.
|
||||
%% http://www.apache.org/licenses/LICENSE-2.0
|
||||
%%
|
||||
%% You should have received a copy of the GNU Lesser General Public
|
||||
%% License along with this library; if not, write to the Free Software
|
||||
%% Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
|
||||
%% USA or retrieve online http://www.opensource.org/licenses/lgpl-3.0.html
|
||||
%% Unless required by applicable law or agreed to in writing, software
|
||||
%% distributed under the License is distributed on an "AS IS" BASIS,
|
||||
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
%% See the License for the specific language governing permissions and
|
||||
%% limitations under the License.
|
||||
%%
|
||||
%% @description
|
||||
%%
|
||||
%% cache bucket process
|
||||
-module(cache_bucket).
|
||||
-behaviour(gen_server).
|
||||
-author('Dmitry Kolesnikov <dmkolesnikov@gmail.com>').
|
||||
|
||||
-include("cache.hrl").
|
||||
|
||||
-export([
|
||||
start_link/2,
|
||||
init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2, code_change/3
|
||||
init/1,
|
||||
terminate/2,
|
||||
handle_call/3,
|
||||
handle_cast/2,
|
||||
handle_info/2,
|
||||
code_change/3
|
||||
]).
|
||||
|
||||
%%
|
||||
%%
|
||||
%% internal bucket state
|
||||
-record(cache, {
|
||||
name :: atom(), %% name of cache bucket
|
||||
heap = [] :: list(), %% cache heap segments
|
||||
name = undefined :: atom(), %% name of cache bucket
|
||||
heap = [] :: list(), %% cache heap segments
|
||||
|
||||
n = ?DEF_CACHE_N :: integer(), %% number of segments
|
||||
ttl = ?DEF_CACHE_TTL :: integer(), %% chunk time to live
|
||||
ttl = ?DEF_CACHE_TTL :: integer(), %% cache time to live
|
||||
policy = ?DEF_CACHE_POLICY :: integer(), %% eviction policy
|
||||
|
||||
cardinality :: integer(), %% cache cardinality
|
||||
memory :: integer(), %% cache memory limit
|
||||
cardinality = undefined :: integer(), %% cache cardinality
|
||||
memory = undefined :: integer(), %% cache memory limit
|
||||
|
||||
quota = ?DEF_CACHE_QUOTA :: integer(), %% quota enforcement timer
|
||||
evict = undefined, %% evict timer
|
||||
|
||||
stats :: any() %% stats functor
|
||||
stats = undefined :: any() %% stats aggregation functor
|
||||
}).
|
||||
|
||||
%% cache segment
|
||||
-record(heap, {
|
||||
id :: integer(), %% segment heap
|
||||
expire :: integer(), %% segment expire time
|
||||
@ -54,8 +57,12 @@
|
||||
memory :: integer() %% segment memory quota
|
||||
}).
|
||||
|
||||
%%
|
||||
%%
|
||||
%%%----------------------------------------------------------------------------
|
||||
%%%
|
||||
%%% Factory
|
||||
%%%
|
||||
%%%----------------------------------------------------------------------------
|
||||
|
||||
start_link({global, Name}, Opts) ->
|
||||
gen_server:start_link({global, Name}, ?MODULE, [Name, Opts], []);
|
||||
|
||||
@ -90,7 +97,7 @@ init([_ | Opts], S) ->
|
||||
init(Opts, S);
|
||||
|
||||
init([], S) ->
|
||||
random:seed(erlang:now()),
|
||||
random:seed(os:timestamp()),
|
||||
Evict = cache_util:mdiv(S#cache.ttl, S#cache.n),
|
||||
init_heap(
|
||||
S#cache{
|
||||
@ -102,7 +109,6 @@ init([], S) ->
|
||||
%%
|
||||
%%
|
||||
terminate(_Reason, _S) ->
|
||||
%cache_heap:free(S#cache.heap),
|
||||
ok.
|
||||
|
||||
%%%----------------------------------------------------------------------------
|
||||
@ -164,6 +170,8 @@ handle_cast({remove, Key}, S) ->
|
||||
handle_cast(_, S) ->
|
||||
{noreply, S}.
|
||||
|
||||
%%
|
||||
%%
|
||||
handle_info(evict, S) ->
|
||||
Now = cache_util:now(),
|
||||
case lists:last(S#cache.heap) of
|
||||
@ -188,13 +196,13 @@ handle_info(quota, S) ->
|
||||
N when N =:= S#cache.n ->
|
||||
{noreply,
|
||||
free_heap(
|
||||
S#cache{quota = cache_util:timeout(S#cache.evict, quota)}
|
||||
S#cache{quota = cache_util:timeout(S#cache.quota, quota)}
|
||||
)
|
||||
};
|
||||
_ ->
|
||||
{noreply,
|
||||
init_heap(
|
||||
S#cache{quota = cache_util:timeout(S#cache.evict, quota)}
|
||||
S#cache{quota = cache_util:timeout(S#cache.quota, quota)}
|
||||
)
|
||||
}
|
||||
end;
|
||||
@ -234,8 +242,8 @@ cache_put(Key, Val, #cache{}=S) ->
|
||||
?DEBUG("cache ~p: put ~p to heap ~p~n", [S#cache.name, Key, Head#heap.id]),
|
||||
S.
|
||||
|
||||
cache_put(Key, Val, Time, #cache{}=S) ->
|
||||
case lists:splitwith(fun(X) -> X#heap.expire > Time end, S#cache.heap) of
|
||||
cache_put(Key, Val, Expire, #cache{}=S) ->
|
||||
case lists:splitwith(fun(X) -> X#heap.expire > Expire end, S#cache.heap) of
|
||||
{[], _Tail} ->
|
||||
cache_put(Key, Val, S);
|
||||
{Head, Tail} ->
|
||||
@ -250,18 +258,13 @@ cache_put(Key, Val, Time, #cache{}=S) ->
|
||||
S
|
||||
end.
|
||||
|
||||
%%
|
||||
%% get cache value
|
||||
cache_get(Key, #cache{policy=mru}=S) ->
|
||||
% cache MRU should not move key anywhere because
|
||||
% cache always evicts last generation
|
||||
% MRU caches do not prolong recently used entity
|
||||
case heap_lookup(Key, S#cache.heap) of
|
||||
undefined ->
|
||||
cache_util:stats(S#cache.stats, {cache, S#cache.name, miss}),
|
||||
undefined;
|
||||
{_Heap, Val} ->
|
||||
?DEBUG("cache ~p: get ~p at cell ~p~n", [S#cache.name, Key, Heap#heap.id]),
|
||||
cache_util:stats(S#cache.stats, {cache, S#cache.name, hit}),
|
||||
Val
|
||||
end;
|
||||
% fall-back to cache lookup
|
||||
cache_lookup(Key, S);
|
||||
|
||||
cache_get(Key, #cache{}=S) ->
|
||||
Head = hd(S#cache.heap),
|
||||
@ -281,6 +284,8 @@ cache_get(Key, #cache{}=S) ->
|
||||
Val
|
||||
end.
|
||||
|
||||
%%
|
||||
%% lookup cache value
|
||||
cache_lookup(Key, #cache{}=S) ->
|
||||
case heap_lookup(Key, S#cache.heap) of
|
||||
undefined ->
|
||||
@ -292,6 +297,8 @@ cache_lookup(Key, #cache{}=S) ->
|
||||
Val
|
||||
end.
|
||||
|
||||
%%
|
||||
%% check if key exists
|
||||
cache_has(Key, #cache{}=S) ->
|
||||
case heap_has(Key, S#cache.heap) of
|
||||
false ->
|
||||
@ -301,6 +308,8 @@ cache_has(Key, #cache{}=S) ->
|
||||
true
|
||||
end.
|
||||
|
||||
%%
|
||||
%% check key ttl
|
||||
cache_ttl(Key, #cache{}=S) ->
|
||||
case heap_has(Key, S#cache.heap) of
|
||||
false ->
|
||||
@ -309,6 +318,8 @@ cache_ttl(Key, #cache{}=S) ->
|
||||
Heap#heap.expire - cache_util:now()
|
||||
end.
|
||||
|
||||
%%
|
||||
%%
|
||||
cache_remove(Key, #cache{}=S) ->
|
||||
lists:foreach(
|
||||
fun(X) -> ets:delete(X#heap.id, Key) end,
|
||||
@ -341,22 +352,6 @@ heap_has(_Key, []) ->
|
||||
false.
|
||||
|
||||
|
||||
% %%
|
||||
% %%
|
||||
% remove(Key, S) ->
|
||||
% Cell = evict_key(Key, cache_heap:cells(S#cache.heap)),
|
||||
% ?DEBUG("cache ~p: remove ~p in cell ~p~n", [S#cache.name, Key, Cell]),
|
||||
% S.
|
||||
|
||||
% %%
|
||||
% %%
|
||||
% member(Key, S) ->
|
||||
% dowhile(
|
||||
% fun(X) -> ets:member(X, Key) end,
|
||||
% cache_heap:cells(S#cache.heap)
|
||||
% ).
|
||||
|
||||
|
||||
%%
|
||||
%% init cache heap
|
||||
init_heap(#cache{}=S) ->
|
||||
@ -387,7 +382,7 @@ free_heap(#cache{}=S) ->
|
||||
).
|
||||
|
||||
%%
|
||||
%%
|
||||
%% heap policy check
|
||||
is_heap_out_of_quota(#heap{}=H) ->
|
||||
is_out_of_memory(H) orelse is_out_of_capacity(H).
|
||||
|
||||
|
@ -1,25 +1,23 @@
|
||||
%%
|
||||
%% Copyright (c) 2012, Dmitry Kolesnikov
|
||||
%% All Rights Reserved.
|
||||
%% Copyright 2012 Dmitry Kolesnikov, All Rights Reserved
|
||||
%%
|
||||
%% This library is free software; you can redistribute it and/or modify
|
||||
%% it under the terms of the GNU Lesser General Public License, version 3.0
|
||||
%% as published by the Free Software Foundation (the "License").
|
||||
%% Licensed under the Apache License, Version 2.0 (the "License");
|
||||
%% you may not use this file except in compliance with the License.
|
||||
%% You may obtain a copy of the License at
|
||||
%%
|
||||
%% Software distributed under the License is distributed on an "AS IS"
|
||||
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
|
||||
%% the License for the specific language governing rights and limitations
|
||||
%% under the License.
|
||||
%% http://www.apache.org/licenses/LICENSE-2.0
|
||||
%%
|
||||
%% You should have received a copy of the GNU Lesser General Public
|
||||
%% License along with this library; if not, write to the Free Software
|
||||
%% Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
|
||||
%% USA or retrieve online http://www.opensource.org/licenses/lgpl-3.0.html
|
||||
%% Unless required by applicable law or agreed to in writing, software
|
||||
%% distributed under the License is distributed on an "AS IS" BASIS,
|
||||
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
%% See the License for the specific language governing permissions and
|
||||
%% limitations under the License.
|
||||
%%
|
||||
%% @description
|
||||
%% root cache supervisor
|
||||
-module(cache_sup).
|
||||
-behaviour(supervisor).
|
||||
-author('Dmitry Kolesnikov <dmkolesnikov@gmail.com>').
|
||||
|
||||
-export([start_link/0, init/1]).
|
||||
|
||||
|
@ -1,23 +1,20 @@
|
||||
%%
|
||||
%% Copyright (c) 2012, Dmitry Kolesnikov
|
||||
%% All Rights Reserved.
|
||||
%% Copyright 2012 Dmitry Kolesnikov, All Rights Reserved
|
||||
%%
|
||||
%% This library is free software; you can redistribute it and/or modify
|
||||
%% it under the terms of the GNU Lesser General Public License, version 3.0
|
||||
%% as published by the Free Software Foundation (the "License").
|
||||
%% Licensed under the Apache License, Version 2.0 (the "License");
|
||||
%% you may not use this file except in compliance with the License.
|
||||
%% You may obtain a copy of the License at
|
||||
%%
|
||||
%% Software distributed under the License is distributed on an "AS IS"
|
||||
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
|
||||
%% the License for the specific language governing rights and limitations
|
||||
%% under the License.
|
||||
%% http://www.apache.org/licenses/LICENSE-2.0
|
||||
%%
|
||||
%% You should have received a copy of the GNU Lesser General Public
|
||||
%% License along with this library; if not, write to the Free Software
|
||||
%% Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
|
||||
%% USA or retrieve online http://www.opensource.org/licenses/lgpl-3.0.html
|
||||
%% Unless required by applicable law or agreed to in writing, software
|
||||
%% distributed under the License is distributed on an "AS IS" BASIS,
|
||||
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
%% See the License for the specific language governing permissions and
|
||||
%% limitations under the License.
|
||||
%%
|
||||
%% @description
|
||||
%%
|
||||
%% cache utility
|
||||
-module(cache_util).
|
||||
|
||||
-export([
|
||||
@ -25,31 +22,33 @@
|
||||
]).
|
||||
|
||||
%%
|
||||
%%
|
||||
mdiv(undefined, _) ->
|
||||
%% maybe div
|
||||
mdiv(X, Y)
|
||||
when X =:= undefined orelse Y =:= undefined ->
|
||||
undefined;
|
||||
mdiv(X, Y) ->
|
||||
X div Y.
|
||||
|
||||
%%
|
||||
%%
|
||||
madd(undefined, _) ->
|
||||
%% maybe add
|
||||
madd(X, Y)
|
||||
when X =:= undefined orelse Y =:= undefined ->
|
||||
undefined;
|
||||
madd(X, Y) ->
|
||||
X + Y.
|
||||
|
||||
%%
|
||||
%%
|
||||
mmul(undefined, _) ->
|
||||
%% maybe multiply
|
||||
mmul(X, Y)
|
||||
when X =:= undefined orelse Y =:= undefined ->
|
||||
undefined;
|
||||
mmul(X, Y) ->
|
||||
X * Y.
|
||||
|
||||
|
||||
%%
|
||||
%%
|
||||
now() ->
|
||||
{Mega, Sec, _} = erlang:now(),
|
||||
{Mega, Sec, _} = os:timestamp(),
|
||||
Mega * 1000000 + Sec.
|
||||
|
||||
%%
|
||||
@ -71,9 +70,7 @@ stats(Fun, Counter, Val)
|
||||
Fun(Counter, Val).
|
||||
|
||||
%%
|
||||
%%
|
||||
%%
|
||||
%% re-set alarm after time
|
||||
%% set / reset timeout
|
||||
timeout(T, Msg)
|
||||
when is_integer(T) ->
|
||||
{clock, T, erlang:send_after(T, self(), Msg)};
|
||||
|
Loading…
Reference in New Issue
Block a user