bfb225c2e7
Updated to reflect more current information about nodepool-builder. Also corrected section hierarchy so everything in operation.rst is under the Operation heading. Change-Id: Iade9bf7a46f6bec778e69d24491dfa1652a6674c
2.2 KiB
2.2 KiB
Developer's Guide
The following guide is intended for those interested in the inner workings of nodepool and its various processes.
Operation
If you send a SIGUSR2 to one of the daemon processes, Nodepool will
dump a stack trace for each running thread into its debug log. It is
written under the log bucket nodepool.stack_dump. This is
useful for tracking down deadlock or otherwise slow threads.
Nodepool Builder
The following is the overall diagram for the nodepool-builder process and its most important pieces:
+-----------------+
| ZooKeeper |
+-----------------+
^ |
bld | | watch
+------------+ req | | trigger
| client +---------+ | +--------------------+
+------------+ | | NodepoolBuilderApp |
| +---+----------------+
| |
| | start/stop
| |
+-------v-------+ |
| <-------+
+---------> NodePool- <----------+
| +---+ Builder +---+ |
| | | | | |
| | +---------------+ | |
| | | |
done | | start start | | done
| | bld upld | |
| | | |
| | | |
+---------v---+ +---v----------+
| BuildWorker | | UploadWorker |
+-+-------------+ +-+--------------+
| BuildWorker | | UploadWorker |
+-+-------------+ +-+--------------+
| BuildWorker | | UploadWorker |
+-------------+ +--------------+