Hi Kevin,
Could you give a bit more information regarding the performance issue, that would help us all to give better ideas on how to troubleshoot the problem. So far people just seem to be posting a rundown of their own Blackboard builds and specification which is irrelevant because everyone has their own way of running applications like Blackboard so it's not really helpful knowing what someone else has.
First of all, we have been advised many times by Blackboard to get a load balanced solution, which was simply untrue because we resolved a lot of performance issues simply by using the clustering in Blackboard 8. Unfortunately, I know this has been depreciated in version 9 so they have forced people into load balanced solutions.
Are you in fact running more than one application server? What version of VMware Infrastructure is being used? Are you using a 32bit java on the server or 64bit?
The issue with VMware Infrastructure is unless you have vSphere 4.0 or above, there is some tweaking that has to be done in the VMware settings to enable the 'Enhanced vmxnet driver' for Windows server in version 3.5/3.51 which I believe also changes how the VM is configured for the guest OS. However, if any such reconfiguring is ever done by your IT guys I'd strongly advise they take snapshots of the current environment before proceeding with any changes. Generally, this improves the IO of the network throughput between the tomcat application server and the database server which an improve the response times in Blackboard which is highly transactional.
bb-config.properties also plays a large part in performance issues. You have to ensure there are the right number of maxthreads which is 200 by default to support the number of users but this also means having enough available memory space in your tomcat java instance. The default can support roughly 2000 user sessions before you might start experiencing issues with Blackboard i.e. each thread requires 10Mb of memory space, supporting 10 user sessions (1Mb per user)
Anyway, looking at those two things are a start and also following Blackboard's guidelines in housekeeping which means deleting NULL sessions, queued tasks and ensuring that the activity_accumulator has no more than 15 million records in the main database. If the sync between the main and stats database has fallen behind then use the command line admin tool to force the accumulator to be purged from the live database. Start with a high number of days to retain i.e. above 180 so for instance keep 270 days, then run again at 240 days, then 210, then 180 and so on because if you try to push a large number of records at once it will time-out.
I hope some of this might help.
Cheers,
Richard
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