Memory management during load testing
Hi folks, We're doing some load testing on our application - particularly focused on a registration process. We're monitoring the test with a number of tools, including FusionReactor. As the test progresses, it's pretty easy to see the Memory Used statistic climbing. That's expected but we'd obviously like this to be as low impact on the memory used as possible. So, I'd like to have a better understanding of what exactly constitutes memory usage (as measured by FusionReactor) and what, if anything, can we do to make it more efficient. I assume that a large query will grab a lot of memory. But, are there other drivers? Any insights into exactly what is in there and how to limit it appropriately to keep memory allocation down during high load periods. Thanks in advance! Nick ~| Order the Adobe Coldfusion Anthology now! http://www.amazon.com/Adobe-Coldfusion-Anthology/dp/1430272155/?tag=houseoffusion Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:354889 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/groups/cf-talk/unsubscribe.cfm
Re: Memory management during load testing
We're doing some load testing on our application - particularly focused on a registration process. We're monitoring the test with a number of tools, including FusionReactor. As the test progresses, it's pretty easy to see the Memory Used statistic climbing. That's expected but we'd obviously like this to be as low impact on the memory used as possible. So, I'd like to have a better understanding of what exactly constitutes memory usage (as measured by FusionReactor) and what, if anything, can we do to make it more efficient. I assume that a large query will grab a lot of memory. But, are there other drivers? Any insights into exactly what is in there and how to limit it appropriately to keep memory allocation down during high load periods. Why do you want to keep memory allocation down? That's the point of having memory - so your applications can use it! You shouldn't have to worry about it unless you're using more than you have. And, ideally, you should be on a 64-bit system so that you can more effectively use the memory you have. (effectively in most cases, of course, not all) Dave Watts, CTO, Fig Leaf Software http://www.figleaf.com/ http://training.figleaf.com/ Fig Leaf Software is a Veteran-Owned Small Business (VOSB) on GSA Schedule, and provides the highest caliber vendor-authorized instruction at our training centers, online, or onsite. ~| Order the Adobe Coldfusion Anthology now! http://www.amazon.com/Adobe-Coldfusion-Anthology/dp/1430272155/?tag=houseoffusion Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:354892 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/groups/cf-talk/unsubscribe.cfm
Re: Memory management during load testing
Hi Dave, Yes, we are on 64 bit with CF9 and a pretty good amount of memory allocated to the jvm (I'd have to check to find out exactly how much). As our load test progresses, the memory used stat in FusionReactor got as high as 75% for a little while. CF / Garbage collection seems pretty good about reducing it, but the concern is that it goes higher (90%+) and then we get a real slow down in performance, requests pile up, etc. FusionReactor does a good job of breaking down memory used into different types so that is something that we need to look at more closely. But, in general and for this test in particular, we are trying to make sure that we aren't overloading memory unnecessarily. Nick ~| Order the Adobe Coldfusion Anthology now! http://www.amazon.com/Adobe-Coldfusion-Anthology/dp/1430272155/?tag=houseoffusion Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:354893 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/groups/cf-talk/unsubscribe.cfm
Re: Memory management during load testing
Sounds like you are on the right track by using FusionReactor. Somewhat refreshing to see someone this concerned with memory usage in the age of affordable hardware. If everyone was like this our shared CF servers would probably be much happier. My example, we had a template that just did a port scan and we put it in our billing app for simplicity sake. At first there were only about 10 cron jobs hitting it per minute, but then got to about 500. We continually had issues with memory and slow down in the cluster. So we started looking at the server monitoring and eventually figured out the number of sessions spawning from that template was the issue. We didn't account for the fact we have a fairly good size default session in the billing app, coupled with the session timeout being 4 hours. Over time it caused the issue. So we put the file in it's own sessionless app, and a week of misery was gone. Byron Mann Lead Engineer Architect HostMySite.com ~| Order the Adobe Coldfusion Anthology now! http://www.amazon.com/Adobe-Coldfusion-Anthology/dp/1430272155/?tag=houseoffusion Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:354899 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/groups/cf-talk/unsubscribe.cfm
