What does “GC--” mean in a java garbage collection log?

Question

We\'ve turned on verbose GC logging to keep track of a known memory leak and got the following entries in the log:

...
3607872.687: [GC 471630K->390767K(4         


        

Answer 1

I got the following from here:

The first two lines indicate you had two minor collections and one major one. The numbers before and after the arrow indicate the combined size of live objects before and after garbage collection, respectively. After minor collections the count includes objects that aren't necessarily alive but can't be reclaimed, either because they are directly alive, or because they are within or referenced from the tenured generation. The number in parenthesis s the total available space, not counting the space in the permanent generation, which is the total heap minus one The format for the major collection in the third line is similar. The flag -XX:+PrintGCDetails prints additional information about the collections. The additional information printed with this flag is liable to change with each version of the virtual machine. The additional output with the -XX:+PrintGCDetails flag in particular changes with the needs of the development of the Java Virtual Machine. of the survivor spaces. The minor collection took about a quarter of a second.