DataBase access on newVM - very high CPU use.

Original issue 1280 created by codenameone on 2015-01-13T22:32:32.000Z:

Notes sent to Shai:

I just took this DBDemo - https://code.google.com/p/codenameone/source/browse/trunk/Demos/SQLSample/src/com/codename1/db/DBDemo.java

Running on the oldVM CPU use when idle doesn't even register on the activity monitor trace highlights. Running on the newVM the demo uses 100%+ CPU. If you leave it idle on the newVM for a minute or two then it will take a long time to respond to touch events.

Adding or deleting rows on both VMs show a spike in CPU and sometimes an increase in memory, but the oldVM is sitting under 20% where as the newVM goes well over 100%.

I'm seeing the knock on effect of in an app that uses a number of automated actions on the database when it starts up is that CPU can spike to > 200% and memory can increase beyond what the device can support causing a crash. The DBDemo.java shows the issue but not to the same level as a full app.

Comment #1 originally posted by codenameone on 2015-01-14T09:42:36.000Z:

It seems that the mark portion of the GC algorithm dealing with statics got into an infinite loop and was unable to escape it. This should be patched in newer builds with the next server update.
It might also explain out of memory issues since GC was effectively dead.