Van:

to answer your question, yes I run the test a lot of times and they always give the comparable answer on both servers, it should not be issue of vm initializatin.

both machine are 64 bits, linux is redhat 5 and windows is 7.

on Linux, the startup parameter is:

17:03:26,025 DEBUG [org.jboss.as.config] (MSC service thread 1-7) VM Arguments: -D[Standalone] -XX:+UseCompressedOops -Xms1024m -Xmx4096m -XX:MaxPermSize=512m -Djava.net.preferIPv4Stack=true -Dorg.jboss.resolver.warning=true -Dsun.rmi.dgc.client.gcInterval=3600000 -Dsun.rmi.dgc.server.gcInterval=3600000 -Djboss.modules.system.pkgs=org.jboss.byteman -Djava.awt.headless=true -Djboss.server.default.config=standalone.xml -agentlib:jdwp=transport=dt_socket,address=8787,server=y,suspend=n

on Windows, the startup parameter is:

15:14:02,962 DEBUG [org.jboss.as.config] (MSC service thread 1-6) VM Arguments: -XX:+TieredCompilation -XX:+UseCompressedOops -Dprogram.name=standalone.bat -Xms1024M -Xmx4096M -XX:MaxPermSize=512M -Dsun.rmi.dgc.client.gcInterval=3600000 -Dsun.rmi.dgc.server.gcInterval=3600000 -Djava.net.preferIPv4Stack=true -Dorg.jboss.resolver.warning=true -Djboss.modules.system.pkgs=org.jboss.byteman -Djboss.server.default.config=standalone.xml -Xrunjdwp:transport=dt_socket,address=8787,server=y,suspend=n

thanks

Kevin

Also, I forgot to mention, we are using Teiid 8.4.0 final.

a little bit background on what we are doing, we started from top level entity and then retrieve its related entities(parents/childeren).

the number I give is for 500 top level entities. there is a mistake on windows number, the client reported 54s to finish, and teiid processing time is 34s.

today I run with just 1 top level entities. and turned on the teiid TRANSPORT log for both windows and linux.

then I exact the time when a request received by server to long [] recv, and when the request sent out from server long[] send.

The ∑(send[i] -recv[i]) represents the total teiid process time, the ∑(recv[i+1] -send[i]) represents the network time+client process time.

the number for linux are 197ms/1960ms, while for windows they are 112ms/777ms.

The number definitely shows that on linux it took more time to send/recv messages, 1960ms v.s  777ms.

The jboss server use XNIO to handle socket request, is it possible the problem is there and how can we configure it to improve its performance?

thanks

Kevin

Ramesh:

thanks, I produce the command log, it is for just 1 top level entity. see attached, let me know what do you find. BTW, what is the difference between user command and data source command?

Kevin

the teiid process the request does not differ much on both linux and windows, if you read my previos post carefully we are thinking the problem is on the network layer, the sending/receiving took much more time on linux machine.   In our test case, the client is a separate jdbc program running on the same machine.

On you server side, is your send() call blocking call? or it will just hand the message over to network layer and return.

the profiling does not help, it did not show hotspot.

thanks,

Kevin

Thanks Steven. Any advice on how to debug the problem?

Thanks Ramesh.

We are using Sun JVM 1.6,  what JVM do you recommend? Is there any particular parameter need to be set?

the client and server are running at the same machine, different process and use loopback interface, also use real IP and it behaves the same.

We also test the other cases, client/server on different machines, in those cases, the performance is also not good as client/server all on the same Windows machine.

the test is using 100 top level entities.