I already use Yourkit but it doesn't seems a load problem. The delay is not spread over all operaions but concentred in only one or two and allways takes 4 secs more than the normal operation time.
Could You suggest how to use Yourkit in this schenario ? Tks Tullio ________________________________ Da: Mark Thomas <ma...@apache.org> Inviato: lunedì 3 ottobre 2016 10.39 A: Tomcat Users List Oggetto: Re: Strange wait time in my application - Tomcat 7.0.67 On 03/10/2016 08:56, Tullio Bettinazzi wrote: > I've an application under tomcat. > When only a one or two users works on it everithing is ok. > When the number of users grows the application slows down. > Is not a memory nor a cpu problem : using top I see the system resources > quite free. > I don't see relevant garbage collection : heap size and permgen have correct > dimentions. > No other applications are running on the system. > I log more or less every relevant operation in my system (db query and so on) > and I see that every slowdown is concentered in a single operation. > I mean all operations take "normal" time but one or two of them take 4 > seconds more. > The "slowing" operations are not the same in different executions, and theydo > not have a specific type (not only DB query, not only DB stored procedures, > not only.....). > It seems like if the thread is frozen for a fixed amount fo time (4 seconds > more or less) and then it restarts. > I don't think it's a "queue" problem because otherwise the wait time would be > unperdictable and not a "fixed" 4 seconds time. > I don't know any parameter impacting on that behaviour. > I use Tomcat 7.0.32 with JVM 1.7.0.67 on a Linux server. > Could someone suggest a solution for my problem or, at least, an > investigation strategy. https://www.yourkit.com/java/profiler/features/ Performance and Memory Java Profiler - YourKit Java Profiler<https://www.yourkit.com/java/profiler/features/> www.yourkit.com Easy to use performance and memory profiler for .NET framework. Supports ASP.NET, Silverlight, .NET Windows services and more. Mark --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org