java process running through apache tomcat hangs suddenly where no exception thrown in application log!

Hello Sunil!

 Greetings.

 Your thread dumps looks normal. I don't see any unsual behaviour. Your application can hang in the middle abruptly due to several reasons. Some of them are:

a. Garbage collection pauses

b. Network connectivity

c. Load balancer routing issue

d. Heavy CPU consumption of threads

e. Operating System running with old patches

f. Memory Leak

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 So just thread dumps is not enough to diagnose the problem. You have captured only thread dump, that too one snapshot of it. It's always a good practice to capture 3 thread dumps in a gap of 10 seconds between each one. Besides thread dumps you might have to capture other logs to do thorough analysis. You may consider using tools like yCrash, which would captures application level logs (like GC logs, 3 snapshots of thread dumps, heap dumps) and system level logs (like top, top -H, netstat, vmstat, iostat, dmesg, diskusage...) and does complete analysis to identify the root cause of the problem. You can register here to get a free 14 day trial of the yCrash.