I am seeing something weird behaviour for JVM in dynatrace,in the below screenshot for survivor space from 8 PM-12PM I am not seeing any data and at the same time the old gen is reached high and we are getting high GC suspension time and also application timeouts happening.
so my question is why survivor space is not consuming any memory during that time and old gen memory is increasing.can someone help me in understanding this.
I probably can't add much but survivor space is where the survivors of young gen garbage collection go, and given the young gen garbage collection stops once the old gen becomes full and old gen garbage collection kicks in heavily that is probably why the survivor space stops being used. The old gen usage is constantly trending upwards until it is full so that is probably where you should start looking. It appears to be a memory leak.
This would be a good starting point to investigate though note you'll probably need to include some developers with knowledge of the application to really get into it: