-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Vijay,
On 10/13/2010 7:35 PM, Vijay Menon wrote: > We're scaling to satisfactory loads of 250 concurrent > requests serving pages in 0.5 seconds. Excellent (assuming that 0.5 seconds is acceptable to your team). > The other test scenario is where the tomcat instance is kept idle > and a single request is sent in every 90 or so seconds. In this case, > the response takes about 8 seconds out of which about 6 seconds > cannot be tracked. As the result, what we're finding is that under > high loads, it performs well but under very low loads, it does not. :( > This definitely happens in the > tomcat layer as we've used the FastCommonAccessLogValve logger which > gives the time for the request in Tomcat. I'd like to echo Chuck's suggestion: take Apache httpd out of the equation and run your "load" test against Tomcat directly. > The connector properties > are protocol="AJP/1.3" maxThreads="150" minSpareThreads="25" > maxSpareThreads="75" acceptCount="100" connectionTimeout="20000" > disableUploadTimeout="true" useBodyEncodingForURI="true". If you want your server to be as efficient as possible, you should use an <Executor> which will allow the request processing threads to be destroyed during times of low activity. It's not really that big of a deal, but it's worth mentioning. A couple more questions: 1. How large are the requests you are processing? Is the usage profile the same for "high load" versus "low load" situations -- other than the actual frequency of requests, of course. 2. Are you using a database of any kind? If so, can you post the configuration for that (minus any sensitive information, of course)? 90 seconds would be a very low timeout for a database connection, but it's possible that you have a bottleneck in your application that somehow only appears when you're nearly idle. 3. Is some other process running on the server during these low-load times? Maybe some cron job or heavy reporting operation or something? - -chris -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAky3HvUACgkQ9CaO5/Lv0PDK4gCeOJaCAXqQfB4C9EA0kYdrjRpt 0pAAn2EURuQAExb7lfBahaSdG5u2cshc =Sw5F -----END PGP SIGNATURE----- --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
