One thing to consider is that the times may not be totally in synch. Some threads pending a write to the log might get interrupted while another thread runs. You may see log entries out of order. I have seen this myself and have added System.out.flush() to my logger. It helps but still does not ensure exact order. Make sure you go over the time stamps carefully before you pass too much judgment.
Robert S. Harper Information Access Technology, Inc. -----Original Message----- From: Leon Rosenberg [mailto:[EMAIL PROTECTED] Sent: Wednesday, July 26, 2006 2:35 PM To: Tomcat Users List Subject: Re: Response time banding I would measure at all layers during the request processing to determine whether irregularities occur somewhere. Leon P.S. "the response times as measured by the access log" - don't you have the proper tools for that? JMeter? On 7/26/06, Edward Hibbert <[EMAIL PROTECTED]> wrote: > Odd one, this. I'm posting looking for off the wall suggestions. > Though not too off the wall, please. > > We have an application running under Tomcat. If we analyse the response > times as measured by the access log, then we see that for the same GET > operation there is a distribution of response times. Well, you'd expect > that. > > But while the bulk of response times are below about 0.25 seconds (in > most cases considerably below), there is a banding effect where we get a > cluster of response times around 2 seconds, and another cluster around 5 > seconds, with little or no values in between. > > We've looked at garbage collection as the most likely source of this, > and ruled it out. Has anyone seen anything similar, or got any bright > ideas? > > Regards, > > Edward. > > --------------------------------------------------------------------- To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] --------------------------------------------------------------------- To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
