Problem: Empty gems on canvases as below screenshot



Solution: Each time when we get empty gems an error appears:"com.dsp.xmla.AbstractXMLAClient - Server (http://ccddb244/olap/msmdpump.dll) Error: 503 : Service Unavailable"


The 503 response is not the result of a bad query. And the problem usually occurs when multiple concurrent requests are being made (when multiple users connect, or when you rapidly reload the page in browser).


To solve this issue you need to change some configuration properties in the file "msmdpump.ini" (typically in the ..\initpub\wwwroot folder) of your pump component.

By default it should look like the following:

<ConfigurationSettings>

 <ServerName>localhost</ServerName>

 <SessionTimeout>3600</SessionTimeout>

 <ConnectionPoolSize>100</ConnectionPoolSize>

 <MinThreadPoolSize>0</MinThreadPoolSize>

 <MaxThreadPoolSize>0</MaxThreadPoolSize>

 <MaxThreadsPerClient>4</MaxThreadsPerClient>

</ConfigurationSettings>


Here we need to increase the MaxThreadsPerClient settings and be sure that:

     MaxThreadsPerClient < MinThreadPoolSize < MaxThreadPoolSize


Here are optimal settings:

    <MinThreadPoolSize>200</MinThreadPoolSize>

    <MaxThreadPoolSize>500</MaxThreadPoolSize>

    <MaxThreadsPerClient>100</MaxThreadsPerClient>


And then restart IIS server. This should help.



Links that describes this problem:

https://social.msdn.microsoft.com/Forums/sqlserver/en-US/145502d3-f9ac-4f7f-a45c-23ad86d89af4/503-service-unavailable-response-from-msmdpumpdll?forum=sqlanalysisservices

https://community.oracle.com/thread/2557146