- Allow 1+ object-servers-per-disk deployment enabled by a new > 0 integer config value, "servers_per_port" in the [DEFAULT] config section for object-server and/or replication server configurations. The setting's integer value determines how many different object-server workers handle requests for any single unique local port in the ring. In this mode, the parent swift-object-server process continues to run as the original user (i.e. root if low-port binding is required). It binds to all ports as defined in the ring. It then forks off the specified number of workers per listen socket. The child, per-port servers, drops privileges and behaves pretty much how object-server workers always have with one exception: the ring has unique ports per disk, the object-servers will only handle requests for a single disk. The parent process detects dead servers and restarts them (with the correct listen socket). It starts missing servers when an updated ring file is found with a device on the server with a new port, and kills extraneous servers when their port is no longer found in the ring. The ring files are started at most on the schedule configured in the object-server configuration by every the "ring_check_interval" parameter (same default of 15s). In testing, this deployment configuration (with a value of 3) lowers request latency, improves requests per second, and isolates slow disk IO as compared to the existing "workers" setting. To use this, each device must be added to the ring using a different port.
