Optimize memory allocation

A number of memory allocation optimizations have been implemented. Most
optimizations reduce contention caused by synchronization between
threads during allocation and deallocation of memory. Most notably:
* Synchronization of memory management in scheduler specific allocator
  instances has been rewritten to use lock-free synchronization.
* Synchronization of memory management in scheduler specific
  pre-allocators has been rewritten to use lock-free synchronization.
* The 'mseg_alloc' memory segment allocator now use scheduler specific
  instances instead of one instance. Apart from reducing contention
  this also ensures that memory allocators always create memory
  segments on the local NUMA node on a NUMA system.

2 files changed, 24 insertions, 6 deletions

diff --git a/erts/emulator/sys/unix/erl_unix_sys.h b/erts/emulator/sys/unix/erl_unix_sys.h
index d8d51b192c..9a5ed9f5bc 100644
--- a/erts/emulator/sys/unix/erl_unix_sys.h
+++ b/erts/emulator/sys/unix/erl_unix_sys.h
@@ -129,10 +129,12 @@
 #define HAVE_ERTS_CHECK_IO_DEBUG
 int erts_check_io_debug(void);
 
-
-#ifndef ENABLE_CHILD_WAITER_THREAD
+#ifndef ERTS_SMP
 #  undef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
 #  define ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
+#endif
+
+#ifndef ENABLE_CHILD_WAITER_THREAD
 #  ifdef ERTS_SMP
 #    define ERTS_SMP_SCHEDULERS_NEED_TO_CHECK_CHILDREN
 void erts_check_children(void);
diff --git a/erts/emulator/sys/unix/sys.c b/erts/emulator/sys/unix/sys.c
index 82d2c64d81..15e110a6cc 100644
--- a/erts/emulator/sys/unix/sys.c
+++ b/erts/emulator/sys/unix/sys.c
@@ -263,6 +263,7 @@ int erts_use_kernel_poll = 0;
 struct {
     int (*select)(ErlDrvPort, ErlDrvEvent, int, int);
     int (*event)(ErlDrvPort, ErlDrvEvent, ErlDrvEventData);
+    void (*check_io_as_interrupt)(void);
     void (*check_io_interrupt)(int);
     void (*check_io_interrupt_tmd)(int, long);
     void (*check_io)(int);
@@ -302,6 +303,9 @@ init_check_io(void)
     if (erts_use_kernel_poll) {
 	io_func.select			= driver_select_kp;
 	io_func.event			= driver_event_kp;
+#ifdef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
+	io_func.check_io_as_interrupt	= erts_check_io_async_sig_interrupt_kp;
+#endif
 	io_func.check_io_interrupt	= erts_check_io_interrupt_kp;
 	io_func.check_io_interrupt_tmd	= erts_check_io_interrupt_timed_kp;
 	io_func.check_io		= erts_check_io_kp;
@@ -314,6 +318,9 @@ init_check_io(void)
     else {
 	io_func.select			= driver_select_nkp;
 	io_func.event			= driver_event_nkp;
+#ifdef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
+	io_func.check_io_as_interrupt	= erts_check_io_async_sig_interrupt_nkp;
+#endif
 	io_func.check_io_interrupt	= erts_check_io_interrupt_nkp;
 	io_func.check_io_interrupt_tmd	= erts_check_io_interrupt_timed_nkp;
 	io_func.check_io		= erts_check_io_nkp;
@@ -325,6 +332,11 @@ init_check_io(void)
     }
 }
 
+#ifdef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
+#define ERTS_CHK_IO_AS_INTR()	(*io_func.check_io_as_interrupt)()
+#else
+#define ERTS_CHK_IO_AS_INTR()	(*io_func.check_io_interrupt)(1)
+#endif
 #define ERTS_CHK_IO_INTR	(*io_func.check_io_interrupt)
 #define ERTS_CHK_IO_INTR_TMD	(*io_func.check_io_interrupt_tmd)
 #define ERTS_CHK_IO		(*io_func.check_io)
@@ -339,6 +351,11 @@ init_check_io(void)
     max_files = erts_check_io_max_files();
 }
 
+#ifdef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
+#define ERTS_CHK_IO_AS_INTR()	erts_check_io_async_sig_interrupt()
+#else
+#define ERTS_CHK_IO_AS_INTR()	erts_check_io_interrupt(1)
+#endif
 #define ERTS_CHK_IO_INTR	erts_check_io_interrupt
 #define ERTS_CHK_IO_INTR_TMD	erts_check_io_interrupt_timed
 #define ERTS_CHK_IO		erts_check_io
@@ -346,13 +363,13 @@ init_check_io(void)
 
 #endif
 
-#ifdef ERTS_SMP
 void
 erts_sys_schedule_interrupt(int set)
 {
     ERTS_CHK_IO_INTR(set);
 }
 
+#ifdef ERTS_SMP
 void
 erts_sys_schedule_interrupt_timed(int set, long msec)
 {
@@ -731,7 +748,7 @@ break_requested(void)
       erl_exit(ERTS_INTR_EXIT, "");
 
   ERTS_SET_BREAK_REQUESTED;
-  ERTS_CHK_IO_INTR(1); /* Make sure we don't sleep in poll */
+  ERTS_CHK_IO_AS_INTR(); /* Make sure we don't sleep in poll */
 }
 
 /* set up signal handlers for break and quit */
@@ -1145,7 +1162,7 @@ static RETSIGTYPE onchld(int signum)
     smp_sig_notify('C');
 #else
     children_died = 1;
-    ERTS_CHK_IO_INTR(1); /* Make sure we don't sleep in poll */
+    ERTS_CHK_IO_AS_INTR(); /* Make sure we don't sleep in poll */
 #endif
 }
 
@@ -2853,7 +2870,6 @@ erl_sys_schedule(int runnable)
     ERTS_CHK_IO(!runnable);
     ERTS_SMP_LC_ASSERT(!ERTS_LC_IS_BLOCKING);
 #else
-    ERTS_CHK_IO_INTR(0);
     if (runnable) {
 	ERTS_CHK_IO(0);		/* Poll for I/O */
 	check_async_ready();	/* Check async completions */