nginx+lua+php+redis实现单业务排队系统架构.zip

PHP Memory Cacher ================= ##Key-value storage in memory As a storage may be used: * [APC](http://pecl.php.net/package/APC) * [Redis](http://redis.io) * [Memcache](http://pecl.php.net/package/memcache) * [Shared memory](http://php.net/manual/en/book.shmop.php) All storage objects have one interface, so you can switch them without changing the working code. ##Features: + Tags for keys + "Dog-pile" ("cache miss storm") and "race condition" effects are excluded + Lock, unlock or acquire key just by one command + Auto Unlocker - any locked key will be automatically unlocked (on exit from function or script) + You can select keys via callback-function + One interface for all storages - you can change storage without changing your code + Increment() method can work with arrays, strings and numeric values + MultiAccess class can be used for any resource, to create an access model *one write multiple read* ##Usage: See [demo.php](https://github.com/jamm/Memory/blob/master/demo.php) to get examples of code. You can use MemoryObjects (RedisObject, APCObject, MemcacheObject, SHMObject) as usual key-value storage: get/set/delete. What for this library was designed is to provide additional features, such as Tags or "dog-pile" effect avoidance. In all storages race conditions are excluded, but you can also lock keys to avoid race conditions in your algorithm: for example, see this code: $value = $mem->read('key'); if (some_condition()) $mem->save('key', $value . 'append'); If this code will be executed by 2 scripts simultaneously, 'append' of one script will be lost. To avoid it, you can lock key: if ($mem->lock_key('key', $au)) { if (some_condition()) $mem->save('key', $value . 'append'); } or acquire: if ($mem->acquire_key('key', $au)) { if (some_condition()) $mem->save('key', $value . 'append'); } Difference between these methods is what they will do when key is locked by another process: lock_key() will just return 'false', acquire_key() will wait until key will not be unlocked (maximum time of waiting declared in code). All 'locks' here are *soft*. It means keys aren't locked for write or read, but you can check, if key is 'locked' or not, and what to do with this - is decision of your script. It was designed to avoid dead-locks and unnecessary queues of clients which waits for access the key. Example in code: if ($mem->lock_key('key', $au)) { if (some_condition()) $mem->save('key', $value . 'append'); } else { // key is not hard-locked actually $mem->del('key'); // we can do this // but we can use 'locks' to manage multi-process interactions properly and easy (see previous code examples) } To avoid the "Dog-pile" effect ("cache miss storm", "cache stampede"), we can use second argument of method read() - when time of expiration is near, we can try to lock key, and if key was locked - update value. See example in [demo.php](https://github.com/jamm/Memory/blob/master/demo.php). ##Requirements: You can use each storage separately, requirements are individually for storages ###PHP version: 5.3+ (maybe 5.2+, not checked) ###If you want to use APC: [APC](http://pecl.php.net/package/APC) should be installed, and this setting should be added in php.ini (or apc.ini if you use it) + apc.slam_defense = Off + __recommended:__ apc.user_ttl = 0 ###If you want to use Memcached: [Memcache](http://pecl.php.net/package/memcache) or [Memcached](http://pecl.php.net/package/memcached) PHP extension should be installed. Memcache is not the fastest and not secure enough storage, so use it only when it's necessary. [Read more](http://code.google.com/p/memcached/wiki/WhyNotMemcached) ###If you want to use Redis: [Redis](http://redis.io) server should be installed (in debian/ubuntu: "apt-get install redis-server"). Supported version is 2.4 and below. Also, [phpredis](https://github.com/nicolasff/phpredis) (if installed) can be used as client library - just use `PhpRedisObject` instead of default `RedisObject`. ###If you want to use the Unix shared memory or MultiAccess: PHP should support shm-functions and msg-functions (--enable-shmop --enable-sysvsem --enable-sysvshm --enable-sysvmsg) Should be used only in specific cases (e.g. mutexes), or when other extensions can not be installed. #Storages comparison: **APC** is a very fast and easy to use storage, and it's usually already installed on the host with PHP. If APC can not be used for caching data, or each your php-process uses separate APC instance - use **Redis**. Redis and Memcache can be used for cross-process communication. Also, data in Redis storage will be restored even after server reboot. Don't want to install Redis (it's just 1 line in console :))? Use **Memcache**. If you can't install any third-party packages, you can use **Shared Memory** - but your PHP should be compiled with support of shmop-functions. ##Performance comparison + **APC** - best performance, let speed result of APC in benchmark is 1. + **PhpRedis** - speed 1.23 + **Redis** - speed 1.6 + **Shared memory** - speed 130 + **Memcache** - speed 192 (slowest) Tests: ===== <?php namespace Jamm\Memory\Tests; header('Content-type: text/plain; charset=utf-8'); $testRedisObject = new TestMemoryObject(new \Jamm\Memory\RedisObject('test')); $testRedisObject->RunTests(); $testRedisServer = new TestRedisServer(); $testRedisServer->RunTests(); $printer = new \Jamm\Tester\ResultsPrinter(); $printer->addTests($testRedisObject->getTests()); $printer->addTests($testRedisServer->getTests()); $printer->printResultsLine(); $printer->printFailedTests(); *** _Look at the comments in demo.php for additional info. Ask, what you want to see commented._ License: [MIT](http://en.wikipedia.org/wiki/MIT_License)