Intermittent Long Pauses - clustered Liferay 5.2.3 / Glassfish 2.1.1

[Leo Wadsworth, modificado 13 Anos atrás.]

We are seeing some strange effects on our site, and I wondered if this sounded like something someone here has dealt with. Our site is producing some intermittent long pauses on displaying pages. Using the free tools at webpagetest.org, I see that it isn't everything on the page, just certain items such as particular graphic images. Which items it is varies at different times. The delay seems to be after the connection is established, but before the first byte is sent.

When everything is purring, our site usage is about 2M visits, 3.2M pageviews in a month.

Here's our configuration:

Servers running on Xen v5.5 virtual servers on 12 blades in an HP chassis.
HAProxy version 1.3.21 load balancer for the front end
Clustered Liferay 5.2.3 portal servers
CentOS 5.3 x86_64
Glassfish 2.1.1 application servers
MySQL 5.1
Apache 2.2.3 webservers for certain static content

Any thoughts?

Thanks!
-lee-

[Brian Russell, modificado 12 Anos atrás.]

Were you ever able to figure out this issue? We seem to be facing a similar issue with our set up:

Rackspace Cloud: Red Hat Enterprise 5.5 x86_64 (8g RAM)
Liferay 6.0.6
Glassfish 3.0.1
MySQL 5.5.20
Apache 2.2.22 with JK Connector 1.2.35
Java 1.6.0_31
Java HotSpot 64-Bit Server VM (build 20.6-b01, mixed mode)
Relevant JVM Options: -server -Xms4096m -Xmx4096m -XX:MaxPermSize=512m

- Also edited the default-web.xml to set the development init-param to false and genStrAsCharArray to true for jsp servlet.
- Made the Acceptor Threads -1 to allow server to determine number of processors.
- I also ran: java -XX:+PrintCommandLineFlags -version
to determine the GC running: -XXarallelGCThreads=4 -XX:+UseCompressedOops -XX:+UseParallelGC
- We currently have 7 active portal instances with pretty steady traffic, but it doesn't seem to be related to any of that.

I've had VisualVm running to monitor memory and garbage collection, but it doesn't seem to correlate to the intermittent pauses. I've noticed that if I simply refresh or navigate to another page, the request will be fulfilled immediately. So it seems that the single, intermittent, request is just hanging.

[Hitoshi Ozawa, modificado 12 Anos atrás.]

just certain items such as particular graphic images

If it's a graphic image in image library, it's probably because it takes time to get binary data out of a database.

Apache 2.2.3 webservers for certain static content

If the image you're talking is about a static content on Apache, it's probably Apache checking the cache and putting it in that's slowing it down the first time.