> From: Tony Fountain [mailto:[EMAIL PROTECTED] > Would you happen to know of any good references that walks through how > to trouble shoot Apache related performance issues?
I don't, so I'm going to throw that open to the list here :-). A few obvious pointers from me: - Performance Monitor: %CPU, Memory pages/second, average disk queue length. Over 80% sustained, over 100, or over 2 per spindle in your disk array are "finger in the air" figures for bottlenecks on that kind of resource. - Remember to monitor your database server if it's separate - and the traffic across your net link to/from the RDBMS. I've seen plenty of people scratching their heads over an almost-idle Web server when the database server was thrashing away. - Turn on verbose GCs in the Java VM and watch for significant GC activity. This can also show as spikes of CPU usage, and generally indicates you're short of Java heap space. - The single most common cause of poor webapp performance, in my experience, is poor use of the database. It's easy to send thousands of small queries to the RDBMS - at which point you'll be crippled by time to parse and execute all these queries, plus latency if the RDBMS is on another machine. It's also easy to create big queries that make poor use of indexes, and saturate the RDBMS that way. In general, more hardware doesn't solve the problem; sending the person who built the database and/or webapp on a course on RDB optimisation is the way to go ;-). - Peter --------------------------------------------------------------------- To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]