SoftReference gets garbage collected too early

Question

I\'m on my way with implementing a caching mechanism for my Android application.

I use SoftReference, like many examples I\'ve found. The problem is, w

Answer 1

Jvm follows this simple equation to determine if a soft reference should get cleared:

interval <= free_heap * ms_per_mb

interval is duration between last gc cycle timestamp and the last access timestamp of soft reference. free heap is heap space available at that moment. ms_per_mb is milliseconds allocated to every MB available in heap. (Constant default 1000 ms)

If above equation is false, reference gets cleared.

So, even if you have a lot of free memory, if your soft references have not been accessed for an ample amount of time, they will get cleared.

-XX:SoftRefLRUPolicyMSPerMB= jvm arg can be used to tweak ms_per_mb constant.