Author: markt
Date: Thu Nov 4 14:25:26 2010
New Revision: 1031001
URL: http://svn.apache.org/viewvc?rev=1031001&view=rev
Log:
Fix https://issues.apache.org/bugzilla/show_bug.cgi?id=49730
Correct race condition in StandardThreadExecutor that can lead to long delays
in processing requests. Patch provided by Sylvain Laurent.
Modified:
tomcat/tc6.0.x/trunk/STATUS.txt
tomcat/tc6.0.x/trunk/java/org/apache/catalina/core/StandardThreadExecutor.java
tomcat/tc6.0.x/trunk/webapps/docs/changelog.xml
Modified: tomcat/tc6.0.x/trunk/STATUS.txt
URL:
http://svn.apache.org/viewvc/tomcat/tc6.0.x/trunk/STATUS.txt?rev=1031001&r1=1031000&r2=1031001&view=diff
==============================================================================
--- tomcat/tc6.0.x/trunk/STATUS.txt (original)
+++ tomcat/tc6.0.x/trunk/STATUS.txt Thu Nov 4 14:25:26 2010
@@ -102,13 +102,6 @@ PATCHES PROPOSED TO BACKPORT:
but from debugging it looks that it is called by Tomcat code only
(JspServlet).
-* Fix https://issues.apache.org/bugzilla/show_bug.cgi?id=49730
- Correct race condition in StandardThreadExecutor that can lead to long delays
- in processing requests. Patch provided by Sylvain Laurent.
- https://issues.apache.org/bugzilla/attachment.cgi?id=25865
- +1: markt, rjung, funkman
- -1:
-
* Fix https://issues.apache.org/bugzilla/show_bug.cgi?id=49860
Add support for trailing headers.
http://svn.apache.org/viewvc?rev=1003461&view=rev
Modified:
tomcat/tc6.0.x/trunk/java/org/apache/catalina/core/StandardThreadExecutor.java
URL:
http://svn.apache.org/viewvc/tomcat/tc6.0.x/trunk/java/org/apache/catalina/core/StandardThreadExecutor.java?rev=1031001&r1=1031000&r2=1031001&view=diff
==============================================================================
---
tomcat/tc6.0.x/trunk/java/org/apache/catalina/core/StandardThreadExecutor.java
(original)
+++
tomcat/tc6.0.x/trunk/java/org/apache/catalina/core/StandardThreadExecutor.java
Thu Nov 4 14:25:26 2010
@@ -49,6 +49,11 @@ public class StandardThreadExecutor impl
protected String name;
+ /**
+ * Number of tasks submitted and not yet completed.
+ */
+ protected AtomicInteger submittedTasksCount;
+
private LifecycleSupport lifecycle = new LifecycleSupport(this);
// ---------------------------------------------- Constructors
public StandardThreadExecutor() {
@@ -63,8 +68,17 @@ public class StandardThreadExecutor impl
TaskQueue taskqueue = new TaskQueue();
TaskThreadFactory tf = new TaskThreadFactory(namePrefix);
lifecycle.fireLifecycleEvent(START_EVENT, null);
- executor = new ThreadPoolExecutor(getMinSpareThreads(),
getMaxThreads(), maxIdleTime, TimeUnit.MILLISECONDS,taskqueue, tf);
+ executor = new ThreadPoolExecutor(getMinSpareThreads(),
getMaxThreads(), maxIdleTime, TimeUnit.MILLISECONDS,taskqueue, tf) {
+ @Override
+ protected void afterExecute(Runnable r, Throwable t) {
+ AtomicInteger atomic = submittedTasksCount;
+ if(atomic!=null) {
+ atomic.decrementAndGet();
+ }
+ }
+ };
taskqueue.setParent( (ThreadPoolExecutor) executor);
+ submittedTasksCount = new AtomicInteger();
lifecycle.fireLifecycleEvent(AFTER_START_EVENT, null);
}
@@ -73,16 +87,21 @@ public class StandardThreadExecutor impl
lifecycle.fireLifecycleEvent(STOP_EVENT, null);
if ( executor != null ) executor.shutdown();
executor = null;
+ submittedTasksCount = null;
lifecycle.fireLifecycleEvent(AFTER_STOP_EVENT, null);
}
public void execute(Runnable command) {
if ( executor != null ) {
+ submittedTasksCount.incrementAndGet();
try {
executor.execute(command);
} catch (RejectedExecutionException rx) {
//there could have been contention around the queue
- if ( !( (TaskQueue) executor.getQueue()).force(command) )
throw new RejectedExecutionException();
+ if ( !( (TaskQueue) executor.getQueue()).force(command) ) {
+ submittedTasksCount.decrementAndGet();
+ throw new RejectedExecutionException();
+ }
}
} else throw new IllegalStateException("StandardThreadPool not
started.");
}
@@ -234,13 +253,17 @@ public class StandardThreadExecutor impl
public boolean offer(Runnable o) {
//we can't do any checks
if (parent==null) return super.offer(o);
+ int poolSize = parent.getPoolSize();
//we are maxed out on threads, simply queue the object
if (parent.getPoolSize() == parent.getMaximumPoolSize()) return
super.offer(o);
//we have idle threads, just add it to the queue
- //this is an approximation, so it could use some tuning
- if (parent.getActiveCount()<(parent.getPoolSize())) return
super.offer(o);
+ //note that we don't use getActiveCount(), see BZ 49730
+ AtomicInteger submittedTasksCount =
StandardThreadExecutor.this.submittedTasksCount;
+ if(submittedTasksCount!=null) {
+ if (submittedTasksCount.get()<=poolSize) return
super.offer(o);
+ }
//if we have less threads than maximum force creation of a new
thread
- if (parent.getPoolSize()<parent.getMaximumPoolSize()) return false;
+ if (poolSize<parent.getMaximumPoolSize()) return false;
//if we reached here, we need to add it to the queue
return super.offer(o);
}
Modified: tomcat/tc6.0.x/trunk/webapps/docs/changelog.xml
URL:
http://svn.apache.org/viewvc/tomcat/tc6.0.x/trunk/webapps/docs/changelog.xml?rev=1031001&r1=1031000&r2=1031001&view=diff
==============================================================================
--- tomcat/tc6.0.x/trunk/webapps/docs/changelog.xml (original)
+++ tomcat/tc6.0.x/trunk/webapps/docs/changelog.xml Thu Nov 4 14:25:26 2010
@@ -195,6 +195,11 @@
compressed rather than only setting it if it is compressed. (markt)
</fix>
<fix>
+ <bug>49730</bug>: Fix race condition in StandardThreadExecutor that can
+ lead to long delays in processing requests. Patch provided by Sylvain
+ Laurent. (markt)
+ </fix>
+ <fix>
<bug>49972</bug>: Fix potential thread safe issue when formatting dates
for use in HTTP headers. (markt)
</fix>
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