Add counters to track the maximum amount of memory committed by the heap.

src/flag-definitions.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 484 matching lines @@
 DEFINE_int(gc_interval, -1, "garbage collect after <n> allocations")
 DEFINE_bool(trace_gc, false,
             "print one trace line following each garbage collection")
 DEFINE_bool(trace_gc_nvp, false,
             "print one detailed trace line in name=value format "
             "after each garbage collection")
 DEFINE_bool(trace_gc_ignore_scavenger, false,
             "do not print trace line after scavenger collection")
 DEFINE_bool(print_cumulative_gc_stat, false,
             "print cumulative GC statistics in name=value format on exit")
+DEFINE_bool(print_max_heap_committed, false,
+            "print statistics of the maximum memory committed for the heap "
+            "in name=value format on exit")
 DEFINE_bool(trace_gc_verbose, false,
             "print more details following each garbage collection")
 DEFINE_bool(trace_fragmentation, false,
             "report fragmentation for old pointer and data pages")
 DEFINE_bool(trace_external_memory, false,
             "print amount of external allocated memory after each time "
             "it is adjusted.")
 DEFINE_bool(collect_maps, true,
             "garbage collect maps from which no objects can be reached")
 DEFINE_bool(weak_embedded_maps_in_optimized_code, true,
@@ skipping 364 matching lines @@
 #undef DEFINE_ALIAS_float
 #undef DEFINE_ALIAS_args
 
 #undef FLAG_MODE_DECLARE
 #undef FLAG_MODE_DEFINE
 #undef FLAG_MODE_DEFINE_DEFAULTS
 #undef FLAG_MODE_META
 #undef FLAG_MODE_DEFINE_IMPLICATIONS
 
 #undef COMMA