Add runtime option to enable/disable lcnt stats

Add erts_debug:lock_counters({copy_save, bool()}). This option
enables or disables statistics saving for destroyed processes and
ets-tables. Enabling this might consume a lot of memory.

Add id-numbering for lock classes which is otherwise undefined.

1 files changed, 15 insertions, 0 deletions

diff --git a/erts/emulator/beam/erl_lock_count.h b/erts/emulator/beam/erl_lock_count.h
index 8564c36203..86c85226e4 100644
--- a/erts/emulator/beam/erl_lock_count.h
+++ b/erts/emulator/beam/erl_lock_count.h
@@ -39,6 +39,20 @@
  * 	Each instance of a lock is the unique lock, i.e. set and id in that set.
  * 	For each lock there is a set of statistics with where and what impact
  * 	the lock aqusition had.
+ *
+ * 	Runtime options
+ * 	- suspend, used when internal lock-counting can't be applied. For instance
+ * 	  when allocating a term for the outside and halloc needs to be used.
+ * 	  Default: off.
+ * 	- location, reserved and not used.
+ * 	- proclock, disable proclock counting. Used when performance might be an
+ * 	  issue. Accessible from erts_debug:lock_counters({process_locks, bool()}).
+ * 	  Default: off.
+ * 	- copysave, enable saving of destroyed locks (and thereby its statistics).
+ * 	  If memory constraints is an issue this need to be disabled.
+ * 	  Accessible from erts_debug:lock_counters({copy_save, bool()}).
+ * 	  Default: off.
+ *
  */
 
 #include "sys.h"
@@ -74,6 +88,7 @@
 #define ERTS_LCNT_OPT_SUSPEND   (((Uint16) 1) << 0)
 #define ERTS_LCNT_OPT_LOCATION  (((Uint16) 1) << 1)
 #define ERTS_LCNT_OPT_PROCLOCK  (((Uint16) 1) << 2)
+#define ERTS_LCNT_OPT_COPYSAVE  (((Uint16) 1) << 3)
 
 typedef struct {
     unsigned long s;