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Diffstat (limited to 'doc')
| -rw-r--r-- | doc/gc.rst | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/doc/gc.rst b/doc/gc.rst index bb0088617..7ec4e6d36 100644 --- a/doc/gc.rst +++ b/doc/gc.rst @@ -127,3 +127,20 @@ In addition to ``GC_ref`` and ``GC_unref`` you can avoid the GC by manually allocating memory with procs like ``alloc``, ``allocShared``, or ``allocCStringArray``. The GC won't try to free them, you need to call their respective *dealloc* pairs when you are done with them or they will leak. + + +Heap dump +========= + +The heap dump feature is still in its infancy, but it already proved +useful for us, so it might be useful for you. To get a heap dump, compile +with ``-d:nimTypeNames`` and call ``dumpNumberOfInstances`` at a strategic place in your program. +This produces a list of used types in your program and for every type +the total amount of object instances for this type as well as the total +amount of bytes these instances take up. This list is currently unsorted! +You need to use external shell script hacking to sort it. + +The numbers count the number of objects in all GC heaps, they refer to +all running threads, not only to the current thread. (The current thread +would be the thread that calls ``dumpNumberOfInstances``.) This might +change in later versions. |