Question

I would like to know if there is a way with PHP5.3 to trace the garbage collector activity like in Java with -verbose:gc command line.

I try to know how often and when the collections occurs.

I’m also interesting about the time spent doing the collections.

Answer 1

It seems that you can activate Garbage Collector benchmarking, recompiling PHP with the DGC_BENCH=1 flag. You’ll obtain statistics like these:

GC Statistics
-------------
Runs:               110
Collected:          2072204
Root buffer length: 0
Root buffer peak:   10000

      Possible            Remove from  Marked
        Root    Buffered     buffer     grey
      --------  --------  -----------  ------
ZVAL   7175487   1491291    1241690   3611871
ZOBJ  28506264   1527980     677581   1025731

It’s not a real trace, but that’s the only thing I could find.