Github user revans2 commented on a diff in the pull request:
https://github.com/apache/storm/pull/700#discussion_r39872212
--- Diff: storm-core/src/jvm/backtype/storm/Config.java ---
@@ -1024,6 +1024,48 @@
/**
+ * Whether to enable backpressure in for a certain topology
+ */
+ public static final String TOPOLOGY_BACKPRESSURE_ENABLE =
"topology.backpressure.enable";
+ public static final Object TOPOLOGY_BACKPRESSURE_ENABLE_SCHEMA =
Boolean.class;
+
+ /**
+ * This signifies the tuple congestion in a worker's out-going queue.
+ * When the used ratio of a worker's outgoing queue is higher than the
high watermark,
+ * the backpressure scheme, if enabled, should slow down the tuple
sending speed of
+ * the spouts until reaching the low watermark.
+ */
+ public static final String
BACKPRESSURE_WORKER_HIGH_WATERMARK="backpressure.worker.high.watermark";
+ public static final Object BACKPRESSURE_WORKER_HIGH_WATERMARK_SCHEMA
=ConfigValidation.PositiveNumberValidator;
+
+ /**
+ * This signifies a state that a worker has left the congestion.
+ * If the used ratio of a worker's outgoing queue is lower than the
low watermark,
+ * it notifies the worker to check whether all its executors have also
left congestion,
+ * if yes, it will unset the worker's backpressure flag on the
Zookeeper
+ */
+ public static final String
BACKPRESSURE_WORKER_LOW_WATERMARK="backpressure.worker.low.watermark";
+ public static final Object BACKPRESSURE_WORKER_LOW_WATERMARK_SCHEMA
=ConfigValidation.PositiveNumberValidator;
+
+ /**
+ * This signifies the tuple congestion in an executor's receiving
queue.
+ * When the used ratio of an executor's receiving queue is higher than
the high watermark,
+ * the backpressure scheme, if enabled, should slow down the tuple
sending speed of
+ * the spouts until reaching the low watermark.
+ */
+ public static final String
BACKPRESSURE_EXECUTOR_HIGH_WATERMARK="backpressure.executor.high.watermark";
+ public static final Object BACKPRESSURE_EXECUTOR_HIGH_WATERMARK_SCHEMA
=ConfigValidation.PositiveNumberValidator;
+
+ /**
+ * This signifies a state that an executor has left the congestion.
+ * If the used ratio of an execuotr's receive queue is lower than the
low watermark,
+ * it may notify the worker to check whether all its executors have
also left congestion,
+ * if yes, the worker's backpressure flag will be unset on the
Zookeeper
+ */
+ public static final String
BACKPRESSURE_EXECUTOR_LOW_WATERMARK="backpressure.executor.low.watermark";
+ public static final Object BACKPRESSURE_EXECUTOR_LOW_WATERMARK_SCHEMA
=ConfigValidation.PositiveNumberValidator;
--- End diff --
Looking through the code it looks like these two configs are never used.
BACKPRESSURE_EXECUTOR_HIGH_WATERMARK and
BACKPRESSURE_EXECUTOR_LOW_WATERMARK. I don't see a reason to have different
configs for different queues. Perhaps we can just remove these configs. and
make the description for the other configs more generic.
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---
