Add thread-specific caching for small size classes, based on magazines.

This caching allows for completely lock-free allocation/deallocation in the
steady state, at the expense of likely increased memory use and
fragmentation.

Reduce the default number of arenas to 2*ncpus, since thread-specific
caching typically reduces arena contention.

Modify size class spacing to include ranges of 2^n-spaced, quantum-spaced,
cacheline-spaced, and subpage-spaced size classes.  The advantages are:
fewer size classes, reduced false cacheline sharing, and reduced internal
fragmentation for allocations that are slightly over 512, 1024, etc.

Increase RUN_MAX_SMALL, in order to limit fragmentation for the
subpage-spaced size classes.

Add a size-->bin lookup table for small sizes to simplify translating sizes
to size classes.  Include a hard-coded constant table that is used unless
custom size class spacing is specified at run time.

Add the ability to disable tiny size classes at compile time via
MALLOC_TINY.

1 files changed, 4 insertions, 0 deletions

diff --git a/lib/libthr/thread/thr_exit.c b/lib/libthr/thread/thr_exit.c
index 4b31a60..4e14311 100644
--- a/lib/libthr/thread/thr_exit.c
+++ b/lib/libthr/thread/thr_exit.c
@@ -36,6 +36,7 @@
 #include <pthread.h>
 #include "un-namespace.h"
 
+#include "libc_private.h"
 #include "thr_private.h"
 
 void	_pthread_exit(void *status);
@@ -95,6 +96,9 @@ _pthread_exit(void *status)
 		_thread_cleanupspecific();
 	}
 
+	/* Tell malloc that the thread is exiting. */
+	_malloc_thread_cleanup();
+
 	if (!_thr_isthreaded())
 		exit(0);