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If the child process is in the process of shutting down, and it gets a new request it will return 503 -- Service Unavailable. If the server times out on a file, the client will receive an IOException from the closed socket. Note that all other files that are being processed will end with an IOException from a closed socket when the child process shuts down; e.g. if you send three files to tika-server concurrently, and one of them causes a catastrophic problem requiring the child to shut down, you won't be able to tell which file caused the problems. In the future, we may implement a gentler shutdown than we currently have.

NOTE 1: to specify the JVM args for the child process, prepend the arguments with -J as in -JXmx4g after the -jar tika-server.x.x.jar call as in:

$ java -Dlog4j.configuration=file:log4j_server.xml -jar tika-server-x.x.jar -spawnChild -JXmx4g -JDlog4j.configuration=file:log4j_child.xml}}

NOTE 2: When using the -spawnChild option, clients will need to be aware that the server could be unavailable temporarily while it is restarting.  Clients will need to have a retry logic.

Logging

You can customize logging via the usual log4j commandline argument, e.g. -Dlog4j.configuration=file:log4j_server.xml. If using -spawnChild, specify the configuration for the child process with the -J prepended as in java -jar tika-server-X.Y-jar -spawnChild -JDlog4j.configuration=file:log4j_server.xml. Some important notes for logging in the child process in versions <= 1.19.1: 1) make sure that the debug option is off, and 2) do not log to stdout (this is used for interprocess communication between the parent and child!).

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