[Progress Communities] [Progress OpenEdge ABL] Forum Post: RE: Issues with PAS and network connectivity

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dbeavon

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That is an interesting chart. I'm assuming that it is the same hardware configuration for PASOE and classic. Can you isolate the processes that are consuming the most cpu? I would guess that it is a combination of tomcat process and the _mproapsv(s). But it would be good for you to confirm that. (Sometimes I find that some totally unexpected thing is consuming CPU, like antivirus or cron jobs, or whatever) Also, would you be able to perform some artificial load-testing? Ideally this this activity could be simulated and so that you would have the opportunity to dive into the problem in more depth. In my experience PASOE is a good technology and scales out well. Our round-trip times for APSV requests can get down to around 5 ms when everything is in the same datacenter (even if we are using client/server rather than "shared memory"). The scalability and fault-tolerance of PASOE can be improved by moving PASOE to its own (load-balanced) hosts and switching over to client/server DB connectivity. Of course some parts of the application design may need to be "revisited" in order to accommodate the client/server connectivity to the database. If I understand correctly, for both classic and PASOE you are running the appserver on the same host as the database, with a shared memory connections. The remote clients are using the APSV transport in both cases, and are connected very distantly (over the WAN from another continent). If that is correct then I think you are dealing with at least two different issues. I would suggest breaking the issues apart and working on them separately. Your application crashes, first of all, seem to be happening while interacting with the OE database in shared memory on a single host (both in the case of "classic" and PASOE): --> Consultingwerk.OERA.Query.QueryString at line 0 (/u8/rslive/rsserver/Scl/SmartComponentLibrary/Consultingwerk/OERA/Query/QueryString.r) NewDSQueryString Automate.OERA.AutomateDataAccess at line 73 (/u8/rslive/rsserver/Rs/AutomateFramework/Automate/OERA/AutomateDataAccess.r) Conceptually this data-access between _mproapsv and the shared memory database should not work any differently than it would between _proapsv and the shared memory database. The only difference is that _mproapsv can host multiple sessions in one process, and _proapsv hosts only a single session per process. I'm not sure I've heard of a lot of bugs that would affect _mproapsv shared-memory connectivity, but not the corresponding _proapsv shared-memory connectivity. Maybe it is worth googling? Another thing that might be helpful is to check and see if switching to client-server (-H -S) would avoid the crashing. We connect to the database strictly via client-server, and we only run PASOE on windows. Perhaps one of those two things is making the difference and prevents us from seeing the crashing. The second problem you are experiencing seems to be performance issues (and related network drops). I'm assuming you are suspicious of the APSV transport between tomcat and the (very) remote appserver clients. Those types of issues should generally show up in the PASOE "session-manager" logs, written on behalf of tomcat sessions. I would scrutinize the session-manager logs (and *not* so much the agent logs). Again the crashing of your msagents is probably not directly related to performance/network issues (since the msagent interaction is with the *database*, and not with the remote PASOE clients). It is the tomcat server that is interacting with remote clients across the WAN. To troubleshoot the remote APSV clients, you might consider installing the "manager" webapp into pasoe since that could give you better visibility over remote clients. You can also turn up logging for the APSV transport in pasoe. see kb: Progress KB - How to enable debug logging for PAS Web applications Hopefully this helps. I'd be interested to hear your performance comparisons again after you have successfully made the switch to PASOE.

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