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CPU use while query executing on server

[This topic is migrated from our old forums. The original author name has been removed]

I have noticed that DbVis 9.0.4 runs my MacBook CPU up a bit while a single query is executing on the server. In the current case, I have a long running aggregate that takes about 300 seconds to compute a result set of 7 rows. While DbVis "waits" the thread averages 30%, enough to get the laptop fans to spin up. While this is not causing any problems, it may be worth noting. During the query run, I also note the memory meter cycling from about 290MB - 400MB and back, repeating several times. I assume this is the GC cycle, but I am wondering what DbVis could be doing with one tab waiting for a query to complete? Product: DbVisualizer Pro 9.0.4 Build: #1920 (2013/02/19 10:16) Java VM: Java HotSpot(TM) 64-Bit Server VM Java Version: 1.6.0_41 Java Vendor: Apple Inc. OS Name: Mac OS X OS Arch: x86_64 OS Version: 10.8.2

[This reply is migrated from our old forums.]

Re: CPU use while query executing on server
Hi Matt, Yes, the driver runs as part of the DbVisualizer process. I can't think of a good way to see what it's doing, unless a sample from the Mac OS X Activity Monitor can give some clues. The PostgreSQL driver is open source, so one alternative is to study the source code? Best Regards, Hans
[This reply is migrated from our old forums. The original author name has been removed]

Re: CPU use while query executing on server
Is there any way to observe activity that is generated by the JDBC driver, to determine if it is excessively polling? I assume it runs as part of the DbVis process, so the OS monitor can't separate them.
[This reply is migrated from our old forums.]

Re: CPU use while query executing on server
Hi Matt, Some of the CPU usage can probably be explained by DbVisualizer animations, like the spinning wheel for the Task Manager in the status bar and the progress bar, but most of it is probably due to processing in the JDBC driver. I don't know how the driver waits for the result, but it could do some kind of polling. Best Regards, Hans
[This reply is migrated from our old forums. The original author name has been removed]

Re: CPU use while query executing on server
Even more interesting I have a long running SELECT MIN() running against a PostgreSQL database which is using a table scan, and while DbVis waits, it is showing 75% CPU utilization.