Something is dead wrong with vizsqlserver PID #32380, too much memory used... 5X versus #7280...
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We have the same issue with tableau server 9.3.3 which we did not have with 9.1.2. We see that Vizql's consume a lot of memory. Did you find root cause of that on your platform?
Thanks and regards
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Hey Adrian --
VizQLs *do* consume lots of RAM, and the behavior is completely normal. there is no appreciable difference between the way they work in 9.1 and 9.3 so I'm not sure why you're seeing something different.
When you watch the memory consumption on one (or more) machines over time, you'll typically see more and more RAM being used, and then it levels off. Here's a time compressed version of this behavior as a load test with 60 concurrent users execute constant load against Tableau:
See how available RAM goes down sharply between seconds 0 and 500 and then stays about the same? This is normal, but you're seeing it over the course of an hour vs. a couple of days.
You may ALSO see available RAM go "way back up" if Tableau Server chooses to recycle a vizqlserver process. The Server Resource Manager will do that from time to time. This behavior could explain why earlier on in the thread Toby saw one of his VizQLs using lots of RAM, and another "not so much". The process using less RAM was probably "newer" than the other, having recently been recycled.
Now that Logshark is available to the public, one could use the SRM report which it generates to actually see this happening. It's kind of cool!
Like Microsoft SQL server is there a way to limit the amount of memory available for use to the instance of Postgresql Tableau uses?
I have been researching this issue myself (see Clear Sessions on unload--mem usage ). A particular view I am using was a large offender of mem usage even though it's a simple cross-tab.
My viz is using custom sql, so I tried to build it using Tableau only (less complex, but returns same # of records). I get the same mem usage results.
What I did notice: If I publish the cross-tab drilled 'up' to the highest level so minimal records are displaying and expand to the lowest level (most detail/records) I watch the mem usage grow. If I simply leave that page memory stays at that level. IF I drill my hierarchies back up to the highest level before leaving that page/viz I get the memory back.
Side note, I do have vizqlserver.clear_session_on_unload to 'TRUE'.
I don't know what this means, but I find it interesting.
So guys, after read, read and read a lot of thread, kb, online help, I couldn´t understand why Vizqlserver.exe sometimes it´s so high and the server have a lot of memory free, but the performance from Tableau Server is so slow.
Who can say something about this?