Cache

PATHFINDER stores some cached data (SQL query results, key => value cache data) in tmp/cache/directory. This is fine for smaller installations (~ 50 active users). This is the default configuration.

For larger installations or better performance I recommend a in memory cache backend like Redis.

Advantages:

• Redis is an in memory cache that stores all data in your RAM rather than on your slow HDD.
• Redis dumps all data from time2time on your HDD. This helps to keep/reload data on server restart
• Redis has an advanced search/write algorithm that speeds up Pathfinder a lot

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Redis setup [optional]

1. Install Redis PHP extension -> https://serverpilot.io/community/articles/how-to-install-the-php-redis-extension.html
   • Check your showinfo();page for PHP. You should find something like:
   • Go to your /setup page and check the Requirements section:
2. Install Redis server -> https://redis.io/topics/quickstart
3. Setup Redis as an LRU (Least recently used) cache -> https://redis.io/topics/lru-cache
4. [optional] Set Redis as default Session handler for all your PHP projects on your server. Change these lines in your php.ini:

   session.save_handler  = redis
   session.save_path     = "tcp://localhost:6380?database=0"
   

   Hint: Default Redis port is 6380. Redis spawns 15 empty databases on start. We take the first database=0 for all global PHP session data.

5. Change CACHE value in your /app/config.ini file like this: CACHE = redis=localhost:6380:1

   CACHE                =   redis=localhost:6380:1
   SESSION_CACHE        =   default
   

   Hint: We use a fresh DB :1 for all Pathfinder related cache data. Change SESSION_CACHE to default in order to use the global PHP Session handler (see 4.)

Check if everything is working. Go to your /setup page and check the Directories section. If the PHP framework is able to connect to your new Redis server, the CACHE value has changed like this:

If everything is working, the /tmp/cache directory should be empty all the time and is no longer used.