Tomcat 7 Maxthreads issues

Question

I have set the maxThreads as 32, But in my logs I am seeing way more than the actual count.

<Connector port="8080"
                   protocol="HTTP/1.1"
                   maxThreads="32" connectionTimeout="20000" redirectPort="8443"
                   compression="on"
                   compressionMinSize="512"
                   compressableMimeType="application/json"
        />

Logs:

24 Oct 2018 13:27:15,378 [INFO,XXX,http-apr-8080-exec-172]

Does it mean that this is the 172 thread? I thought the thread pool will be limited to 32 since I have given maxThreads. And I dont have any custom executor defined as well

That's the thread ID but it doesn't follow that all the 172 IDs are being used for active threads. I recommend you to run some profiling so you can know for sure how many threads are active in the pool. — Alfabravo, Oct 24 '18 at 18:42
What I expect is the pool should ideally have 25 threads and each getting reused. In that case id wont cross 25 — Renjith, Oct 24 '18 at 18:46
Then, you should not affirm that the ID "won't cross" 25. Please, check the answer — Alfabravo, Oct 24 '18 at 18:57

score 1 · Accepted Answer · answered Oct 24 '18 at 18:56

1

Basically, as explained in this answer, the ID for threads in Java are not guaranteed to start from zero or to be contiguous when created.

Here in the code you can see that their ID is set with a sequence incremented somehow.

Once again, I recommend you to run some profiling tool in your Java app to see the actual number of threads being created in the pool at a given time.

answered Oct 24 '18 at 18:56

Alfabravo

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The pool will shrink down to minSpareThreads="10" (the default value) if threads are not used. If you want more control, configure a separate Executor element. – Konstantin Kolinko Oct 25 '18 at 06:36

Tomcat 7 Maxthreads issues

1 Answers1