Servoy Server takes a lot of CPU

Classic Servoy
1

Yesterday afternoon and this morning we had problems with Servoy on one of our servers.
Servoy server (java.exe) takes a lot of CPU and memory. Our webclient solutions become very slow.
Today (and yesterday) I restarted the service, this solves the problem for a while but is not a solution because I have to throw out a lot of users.

I would like to know how we can find the cause of this problem?
I have two stackdumps of this morning:
http://orderyourflowers.nl/stackdump_30052011_1.txt
http://orderyourflowers.nl/stackdump_30052011_2.txt

and a screenshot of the task manager on our server:

2

you seem to run of of memory, i guess you have a high cpu because of the garbage collections that takes place at a high rate.

I do see a lot of queries being done, or a lot of threads waiting to do a query (many wait for a connection to be freed by another thread)

3

I forgot to check the number of Active connections. We have 18 database servers, most of them are external. And we allow 60 active connections on all those servers. Could that be a problem?

4

not really, but if the server spikes and almost runs out of mem, you should check how many connections there are also in use…

5

Yesterday evening I had the same problem. Only 20 clients where connected, all to the same solution. None of the database server connections where full. We also have 3 batch processes running. We really would like to know what causes the problems. Is there a way to find out which solution, connection or process causes the problem?

6

The simple variant is to make a few stackdumps right after each other with lets say 5 seconds apart. Then we could see what they all are doing.
But if you look at the:

System Information
Heap memory: allocated=547904K, used=284257K, max=699072K

and allocated,used,max are all very close to each other then you just give your machine to little memory or there could be a problem of something taking a lot of memory
This can be profiled with jvisualvm.exe thats inside the JDK (not JRE!) bin directory. If you start that on the same machine (i think you can’t run the servoy server as a service then, because then it wont see it)
connect to it and dump the memory heap.