[DRILL-5994] enable configuring number of Jetty acceptors and selectors

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.11.0
• Fix Version/s: 1.13.0
• Labels: doc-impacting ready-to-commit
• Assignee: Vlad Rozov
• Reporter: Mitchel Labonte
• Reviewer: Timothy Farkas
• Created: 28/Nov/17 14:07
• Updated: 20/Aug/18 12:24
• Resolved: 03/Mar/18 18:48

Description

If the WebServer is launched on a machine that has more than 200 cores, you get the following stack trace:

Exception in thread "main" org.apache.drill.exec.exception.DrillStartupException: Failure during initial startup of Drillbit:
at org.apache.drill.exec.server.Drillbit.start(Drillbit.java:313)
at org.apache.drill.exec.server.Drillbit.start(Drillbit.java:289)
at org.apache.drill.exec.server.Drillbit.start(Drillbit.java:285)
Caused by: java.lang.IllegalStateException: Insufficient max threads in ThreadPool: max=200 < needed=206
at org.eclipse.jetty.server.Server.doStart(Server.java:321)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
at org.eclipse.drill.exec.server.rest.WebServer.start(WebServer.java:197)
at org.eclipse.drill.exec.server.Drillbit.run(Drillbit.java:140)
at org.eclipse.drill.exec.server.Drillbit.start(Drillbit.java:309)
... 2 more

The cause of this is that in the WebServer start method, a Server instance is created with the default constructor, which initializes a QueuedThreadPool with a default maxThreads value of 200, and there is no way to configure this value.

For documentation
New config option - drill.exec.web_server.thread_pool_max drill.exec.http.jetty.server.acceptors (default 1) and drill.exec.http.jetty.server.selectors (default 2).

Issue Links

• causes: DRILL-6693 When a query is started from Drill Web Console, the UI becomes inaccessible until the query is completed
• links to: GitHub Pull Request #1069
• links to: GitHub Pull Request #1148