. Why does GG disappear?
When memory is not enough, low memory killer in Android system would kill less important programs to ensure there is enough free memory. Before GG 5.1, GG is a background service, so it is easily selected and killed. (I tried to make it foreground, but Android 3.3.x~ ignore that. Because this technique is abused, android team decided to change the semantic of some APIs)
. How about now?
Now GG 5.1 gets higher priority than foreground Apps, e.g. games. When memory is not enough, what system can do is killing lower priority programs, i.e. you game.
. Any solution?
So, how to reduce memory pressure? Use "Set Temp Path" to put the temporary data into external storage instead of memory. That could reduce the memory usage. However, that also makes searching much slower. (Especially for Fuzzy search, it really requires lots of memory and time)