• Bob Van Landuyt's avatar
    Move the circuitbreaker check out in a separate process · f1ae1e39
    Bob Van Landuyt authored
    Moving the check out of the general requests, makes sure we don't have
    any slowdown in the regular requests.
    
    To keep the process performing this checks small, the check is still
    performed inside a unicorn. But that is called from a process running
    on the same server.
    
    Because the checks are now done outside normal request, we can have a
    simpler failure strategy:
    
    The check is now performed in the background every
    `circuitbreaker_check_interval`. Failures are logged in redis. The
    failures are reset when the check succeeds. Per check we will try
    `circuitbreaker_access_retries` times within
    `circuitbreaker_storage_timeout` seconds.
    
    When the number of failures exceeds
    `circuitbreaker_failure_count_threshold`, we will block access to the
    storage.
    
    After `failure_reset_time` of no checks, we will clear the stored
    failures. This could happen when the process that performs the checks
    is not running.
    f1ae1e39