tools/README-jack-server.txt

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Jack server
###########

The Jack server's goal is to handle a pool of Jack compiler instances in order to limit memory usage
and benefit from already warm instances.



Starting the server
-------------------

You may need to start the Jack server manually.
Use "jack-admin start-server".



Client info
-----------

The client is a bash script simply named "jack".
It can be configured in "$HOME/.jack-settings"



".jack-settings" file
---------------------

This file contains script shell variables:
"SERVER_HOST": IP address of the server
by default: "SERVER_HOST=127.0.0.1".

"SERVER_PORT_SERVICE": Server service TCP port number. Needs to match the service port number
defined in "$HOME/.jack-server/config.properties" on the server host (See "Server info" below)
by default: "SERVER_PORT_SERVICE=8076".

"SERVER_PORT_ADMIN": Server admin TCP port number. Needs to match the admin port number defined in
"$HOME/.jack-server/config.properties" on the server host (See "Server info" below)
by default: "SERVER_PORT_ADMIN=8077".

"SETTING_VERSION": Internal, do not modify.



Server info
-----------

The server is composed of 2 jars named "jack-server.jar" and "jack-launcher.jar".

Check "Admin" section to know how to install and administrate the Jack server.

The server can also be configured in "$HOME/.jack-server/config.properties".



"config.properties" file
------------------------

It contains Jack server configuration properties.
Description with default values follows:

jack.server.max-service=<number>
  Maximum number of simultaneous Jack tasks. Default is 4.

jack.server.max-jars-size=<size-in-bytes>
  Maximum size for Jars, in bytes. "-1" means no limit. Default is 100 MiB.

jack.server.time-out=<time-in-seconds>
  Time out delay before Jack gets to sleep. When Jack sleeps, its memory usage is reduced, but it is
  slower to wake up. "-1" means "do not sleep". Default is 2 weeks.

jack.server.service.port=<port-number>
  Server service TCP port number. Default is 8076. Needs to match the service port defined in
  "$HOME/.jack-settings" on the client host (See Client section).

jack.server.admin.port=<port-number>
  Server admin TCP port number. Default is 8077. Needs to match the service port defined in
  "$HOME/.jack-settings" on the client host (See Client section).

jack.server.config.version=<version>
  Internal, do not modify.



Server logs
-----------

Server logs can be found by running "jack-admin server-log". Default location is
"$HOME/.jack-server/logs/".



Admin
-----

The "jack-admin" bash script allows to install and administrate the Jack server.
Here are some commands:

$ jack-admin help
Print help.

$ jack-admin install-server jack-launcher.jar jack-server.jar
Install the Jack server.

$ jack-admin uninstall-server
Uninstall the Jack server and all components.

$ jack-admin list jack
List installed versions for Jack.

$ jack-admin update jack jack.jar
Install or update a Jack jar.

$ jack-admin start-server
Start the server.

$ jack-admin stop-server
Stop the server after the last compilation is complete.

$ jack-admin kill-server
Kill the server process immediately, interrupting abruptly ongoing compilations.

$ jack-admin list-server
List Jack server processes.

$ jack-admin server-stat
Print various info about the server and the host.

$ jack-admin server-log
Print log pattern.



Troubleshooting
---------------

If compilation fails on "No Jack server running":

See "Starting the server" above.


If your computer becomes unresponsive during compilation or if you experience Jack compilations
failing on "Out of memory error.":

You can improve the situation by reducing the number of jack simultaneous compilations by editing
your "$HOME/.jack-server/config.properties" and changing jack.server.max-service to a lower value.


If you have trouble starting the server:

This may mean that TCP ports are already in use on your computer. You can try modifying the ports
both in your client and server configurations. See the "Server info" and "Client info" sections.
If it doesn't solve the problem, please report and give us additional information by:
  - Attaching your compilation log.
  - Attaching a zip of "$HOME/.jack-server/".
  - Attaching "$HOME/.jack-settings".
  - Executing "lsof -i TCP:8076", "lsof -i TCP:8077" and attaching the outputs.


If your commands fails on
"Failed to contact Jack server: Problem reading <your home>/.jack-server/client.pem":

This may mean that your server never managed to start, see
"If you have trouble starting the server" above.


If your compilation gets stuck without any progress:

Please report and give us additional information by:
  - Running "jack-admin list-server | awk '{print $2}' | xargs kill -3".
  - Attaching the server log to the bug (see the "Server logs" section).
  - Executing a "jack-admin server-stat" and attaching the output.
  - Attaching "$HOME/.jack-server/logs/outputs.txt".
  - Executing "lsof -i TCP:8076", "lsof -i TCP:8077" and attaching the outputs.