AXL Memory limit

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    This document was generated from CDN thread

    Created by: Laurent TRELET on 11-05-2010 10:35:38 AM
    Hello AXL community !
    I have a problem with my AXL requests since this morning. Every night, i perform requets to get SQL tables via AXL. 
    Since this morning, i have a response i nerver had before :
    <SOAP-ENV:Envelope xmlns:SOAP-ENV="" SOAP-ENV:encodingStyle=""><SOAP-ENV:Header/><SOAP-ENV:Body><SOAP-ENV:Fault><faultcode>SOAP-ENV:Client</faultcode><faultstring>Maximum AXL Memory Allocation Consumed.Please retry once requests in progress have completed</faultstring><detail><axl:Error xmlns:axl=""><axl:code>5009</axl:code><axl:message>Maximum AXL Memory Allocation Consumed.Please retry once requests in progress have completed</axl:message><request>executeSQLQuery</request></axl:Error></detail></SOAP-ENV:Fault></SOAP-ENV:Body></SOAP-ENV:Envelope>
    My request in this example is the following : 
    select skip 0 first 1000 * from device  
    2 days ago, the requet was OK and today, the system seems to be too busy. I know there is a 8MB limit but i'm ok for this point.
    In the AXL logs, i can read : 
    The SQL ResultSet Size.. 3403000
    Request 1273351932329 was process in 84ms
    I tried to reduce the size of the result with this request for example :
    select skip 0 first 800 * from device
    The result is fine. I am not sure it is a result limit problem or not. I didn't change anything on my cluster between yesterday and today...
    Does anybody knows this error ? Can we allocate more ressources for the AXL process ? Is it dangerous ?
    Thanks in advance.

    Subject: RE: AXL Memory limit
    Replied by: David Staudt on 11-05-2010 01:28:38 PM
    The error return can occur if there are other AXL applications executing queries at the same time - there is a 16MB limit across all apps.  Also AXL makes some estimates about the result size based on the first few rows returned - if say the first row of data now contains a long description or otherwise more bytes than for previous estimates, the extrapolated final size calculation may become larger, triggering the throttle even with the same # of rows.
    The memory allocation is for the platform Tomcat JVM, and is currently fixed.  Recommendation would be to reduce the # of rows queried, as you have suggested.

    Subject: RE: AXL Memory limit
    Replied by: Laurent TRELET on 12-05-2010 12:36:56 PM
    Thank you David !
    As usual your answer is relevant !
    I will modify my requets. Some other apps must be executing queries at the same time...
    Thanks again.