Tim Armstrong has posted comments on this change. ( http://gerrit.cloudera.org:8080/11872 )
Change subject: IMPALA-7634: [DOCS] Document the new SHUTDOWN statement ...................................................................... Patch Set 2: (11 comments) http://gerrit.cloudera.org:8080/#/c/11872/2/docs/topics/impala_shutdown.xml File docs/topics/impala_shutdown.xml: http://gerrit.cloudera.org:8080/#/c/11872/2/docs/topics/impala_shutdown.xml@42 PS2, Line 42: The <codeph>SHUTDOWN</codeph> statement performs a graceful shutdown of Impala Daemon. There's a "grace period" behaviour that would be good to briefly document. It means there's a minimum time until the Impala daemon actually shuts down. It's in there as a way to ensure that other Impala daemons have a chance to stop scheduling new work on the executor before it shuts down. Maybe something like: The Impala daemon will notify other Impala daemons that it is shutting down, wait for a grace period, then shut itself down once no more queries or fragments are executing on that daemon. --shutdown_grace_period_s determines the duration of the grace period in seconds. http://gerrit.cloudera.org:8080/#/c/11872/2/docs/topics/impala_shutdown.xml@149 PS2, Line 149: A client can shut down the coordinator <codeph>impalad</codeph> that it is connected to Should we link to the place where the coordinator/executor concepts are defined? http://gerrit.cloudera.org:8080/#/c/11872/2/docs/topics/impala_shutdown.xml@161 PS2, Line 161: </li> The default deadline is determined by the --shutdown_deadline_s flag, which defaults to 1 hour. http://gerrit.cloudera.org:8080/#/c/11872/2/docs/topics/impala_shutdown.xml@164 PS2, Line 164: without causing a service-wide outage maybe just something like "without disrupting running queries." The service-wide outage is a consequence of the lack of graceful shutdown plus some scheduling behaviour so might be a bit too low-level and backward-looking to document here. http://gerrit.cloudera.org:8080/#/c/11872/2/docs/topics/impala_shutdown.xml@170 PS2, Line 170: Coordinators can be shut down without query failures only if there is an out-of-band : mechanism to prevent submission of more queries to the shut down coordinator. I'm wondering if we can drop this sentence? I think the next sentence covers it pretty well. http://gerrit.cloudera.org:8080/#/c/11872/2/docs/topics/impala_shutdown.xml@172 PS2, Line 172: after shutdown This might be a bit pedantic, but maybe something like "after shutdown of that coordinator" just so it's unambiguous that it only applies if that coordinator is shut down. http://gerrit.cloudera.org:8080/#/c/11872/2/docs/topics/impala_shutdown.xml@195 PS2, Line 195: <codeblock>SHUTDOWN(); -- Shut down the current impalad immediately. This actually shuts it down with the default deadline (see above comment) http://gerrit.cloudera.org:8080/#/c/11872/2/docs/topics/impala_shutdown.xml@196 PS2, Line 196: SHUTDOWN('hostname'); -- Shut down impalad running on hostname immediately. Same here http://gerrit.cloudera.org:8080/#/c/11872/2/docs/topics/impala_shutdown.xml@197 PS2, Line 197: SHUTDOWN(\"hostname:1234\"); -- Shut down impalad running on host at port 1234 immediately. Same here http://gerrit.cloudera.org:8080/#/c/11872/2/docs/topics/impala_shutdown.xml@200 PS2, Line 200: SHUTDOWN('hostname:11', 10 * 60); -- Shut down impalad running on hostname at port 11 after 600 seconds. This is really "when all queries running on hostname finish, or after 600 seconds". http://gerrit.cloudera.org:8080/#/c/11872/2/docs/topics/impala_shutdown.xml@201 PS2, Line 201: SHUTDOWN(0); -- Shutdown the current impalad immediately.</codeblock> Same here -- To view, visit http://gerrit.cloudera.org:8080/11872 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: I0cfe4bae1b7966980cdeececa6b959bbecb4a24a Gerrit-Change-Number: 11872 Gerrit-PatchSet: 2 Gerrit-Owner: Alex Rodoni <[email protected]> Gerrit-Reviewer: Bikramjeet Vig <[email protected]> Gerrit-Reviewer: Impala Public Jenkins <[email protected]> Gerrit-Reviewer: Tim Armstrong <[email protected]> Gerrit-Comment-Date: Mon, 05 Nov 2018 19:47:41 +0000 Gerrit-HasComments: Yes
