Improve configuration of process and port tables

17 files changed, 397 insertions, 181 deletions

diff --git a/erts/doc/src/erl.xml b/erts/doc/src/erl.xml
index 4ef3e089a6..f7d8d37fd3 100644
--- a/erts/doc/src/erl.xml
+++ b/erts/doc/src/erl.xml
@@ -586,13 +586,51 @@
           <seealso marker="erts_alloc">erts_alloc(3)</seealso> for
           further information.</p>
       </item>
+      <tag><c><![CDATA[+n]]></c></tag>
+      <item>
+	<p>Enable synchronous message passing to ports.</p>
+	<p>As of OTP-R16 message passing to ports are truly asynchronously
+	   implemented. Correctly written Erlang programs should be able
+	   to handle this without any issues. Bugs in existing Erlang
+	   programs that make false assumptions about message passing to
+	   ports may, however, be tricky to find. This switch has been
+	   introduced in order to at least make it easier to compare
+	   behaviors during a transition period. Note that this flag is
+	   deprecated as of its introduction, and is scheduled for removal
+	   in OTP-R17.</p>
+      </item>
       <tag><marker id="max_processes"><c><![CDATA[+P Number]]></c></marker></tag>
       <item>
-        <p>Sets the maximum number of concurrent processes for this
-          system. <c><![CDATA[Number]]></c> must be in the range 16..134217727.
-	  Default is 32768.</p>
-        <p><em>NOTE</em>: It is possible to choose any value in the range
-	  but powers of 2 perform best.</p>
+	<p>Sets the maximum number of simultaneously existing processes for this
+          system. Valid range for <c>Number</c> is <c>[1024-134217727]</c></p>
+	<p><em>NOTE</em>: The actual maximum chosen may be much larger than
+	the <c>Number</c> passed. Currently the runtime system often,
+	but not always, chooses a value that is a power of 2. This might,
+	however, be changed in the future. The actual value chosen can be
+	checked by calling
+	<seealso marker="erlang#system_info_process_limit">erlang:system_info(process_limit)</seealso>.</p>
+	<p>The default value is <c>262144</c></p>
+      </item>
+      <tag><marker id="max_ports"><c><![CDATA[+Q Number]]></c></marker></tag>
+      <item>
+	<p>Sets the maximum number of simultaneously existing ports for this
+          system. Valid range for <c>Number</c> is <c>[1024-134217727]</c></p>
+	<p><em>NOTE</em>: The actual maximum chosen may be much larger than
+	the actual <c>Number</c> passed. Currently the runtime system often,
+	but not always, chooses a value that is a power of 2. This might,
+	however, be changed in the future. The actual value chosen can be
+	checked by calling
+	<seealso marker="erlang#system_info_port_limit">erlang:system_info(port_limit)</seealso>.</p>
+	<p>The default value used is normally <c>65536</c>. However, if
+	the runtime system is able to determine maximum amount of file
+	descriptors that it is allowed to open and this value is larger
+	than <c>65536</c>, the chosen value will increased to a value
+	larger or equal to the maximum amount of file descriptors that
+	can be opened.</p>
+	<p>Previously the environment variable <c>ERL_MAX_PORTS</c> was used
+	for setting the maximum number of simultaneously existing ports. This
+	environment variable is deprecated, and scheduled for removal in
+	OTP-R17, but can still be used.</p>
       </item>
       <tag><marker id="compat_rel"><c><![CDATA[+R ReleaseNumber]]></c></marker></tag>
       <item>
@@ -601,21 +639,14 @@
           default. This flags sets the emulator in compatibility mode
           with an earlier Erlang/OTP release <c><![CDATA[ReleaseNumber]]></c>.
           The release number must be in the range
-          <c><![CDATA[7..<current release>]]></c>. This limits the emulator,
-          making it possible for it to communicate with Erlang nodes
-          (as well as C- and Java nodes) running that earlier release.</p>
-        <p>For example, an R10 node is not automatically compatible
-          with an R9 node, but R10 nodes started with the <c><![CDATA[+R 9]]></c>
-          flag can co-exist with R9 nodes in the same distributed
-          Erlang system, they are R9-compatible.</p>
+          <c><![CDATA[<current release>-2..<current release>]]></c>. This
+	  limits the emulator, making it possible for it to communicate
+	  with Erlang nodes (as well as C- and Java nodes) running that
+	earlier release.</p>
         <p>Note: Make sure all nodes (Erlang-,  C-, and Java nodes) of
           a distributed Erlang system is of the same Erlang/OTP release,
           or from two different Erlang/OTP releases X and Y, where
           <em>all</em> Y nodes have compatibility mode X.</p>
-        <p>For example: A distributed Erlang system can consist of
-          R10 nodes, or of R9 nodes and R9-compatible R10 nodes, but
-          not of R9 nodes, R9-compatible R10 nodes and "regular" R10
-          nodes, as R9 and "regular" R10 nodes are not compatible.</p>
       </item>
       <tag><c><![CDATA[+r]]></c></tag>
       <item>
@@ -1026,7 +1057,7 @@
           the given number of seconds have elapsed, the emulator will be
           terminated by a SIGALRM signal.</p>
       </item>
-      <tag><c><![CDATA[ERL_AFLAGS]]></c></tag>
+      <tag><marker id="ERL_AFLAGS"><c><![CDATA[ERL_AFLAGS]]></c></marker></tag>
       <item>
         <p>The content of this environment variable will be added to the
           beginning of the command line for <c><![CDATA[erl]]></c>.</p>
@@ -1036,7 +1067,7 @@
           the <c><![CDATA[-extra]]></c> section, i.e. the end of the command line
           following after an <c><![CDATA[-extra]]></c> flag.</p>
       </item>
-      <tag><c><![CDATA[ERL_ZFLAGS]]></c> and <c><![CDATA[ERL_FLAGS]]></c></tag>
+      <tag><marker id="ERL_ZFLAGS"><c><![CDATA[ERL_ZFLAGS]]></c></marker> and <marker id="ERL_FLAGS"><c><![CDATA[ERL_FLAGS]]></c></marker></tag>
       <item>
         <p>The content of these environment variables will be added to the
           end of the command line for <c><![CDATA[erl]]></c>.</p>
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
index 0963904b83..2da456d49f 100644
--- a/erts/doc/src/erlang.xml
+++ b/erts/doc/src/erlang.xml
@@ -3225,10 +3225,11 @@ os_prompt% </pre>
           the owning process using signals of the form
           <c>{'EXIT', Port, PosixCode}</c>. See <c>file(3)</c> for
           possible values of <c>PosixCode</c>.</p>
-        <p><marker id="ERL_MAX_PORTS"></marker>
-          The maximum number of ports that can be open at the same
-          time is 1024 by default, but can be configured by
-          the environment variable <c>ERL_MAX_PORTS</c>.</p>
+	  <p>The maximum number of ports that can be open at the same
+          time can be configured by passing the 
+	  <seealso marker="erl#max_ports"><c>+Q</c></seealso>
+	  command line flag to
+	  <seealso marker="erl"><c>erl(1)</c></seealso>.</p>
       </desc>
     </func>
     <func>
@@ -5955,17 +5956,33 @@ ok
           </item>
           <tag><c>process_count</c></tag>
           <item>
+            <p>Returns the number of ports currently existing at
+              the local node as an integer. The same value as
+              <c>length(erlang:ports())</c> returns.</p>
+          </item>
+          <tag><marker id="system_info_port_limit"><c>port_limit</c></marker></tag>
+          <item>
+            <p>Returns the maximum number of simultaneously existing
+              ports at the local node as an integer. This limit
+              can be configured at startup by using the
+              <seealso marker="erl#max_ports"><c>+Q</c></seealso>
+	      command line flag of
+	      <seealso marker="erl"><c>erl(1)</c></seealso>.</p>
+          </item>
+          <tag><c>process_count</c></tag>
+          <item>
             <p>Returns the number of processes currently existing at
               the local node as an integer. The same value as
               <c>length(processes())</c> returns.</p>
           </item>
-          <tag><c>process_limit</c></tag>
+          <tag><marker id="system_info_process_limit"><c>process_limit</c></marker></tag>
           <item>
-            <p>Returns the maximum number of concurrently existing
+            <p>Returns the maximum number of simultaneously existing
               processes at the local node as an integer. This limit
-              can be configured at startup by using the command line
-              flag <c>+P</c>, see
-              <seealso marker="erts:erl#max_processes">erl(1)</seealso>.</p>
+              can be configured at startup by using the
+              <seealso marker="erl#max_processes"><c>+P</c></seealso>
+	      command line flag of
+	      <seealso marker="erl"><c>erl(1)</c></seealso>.</p>
           </item>
           <tag><c>procs</c></tag>
           <item>
diff --git a/erts/emulator/beam/erl_init.c b/erts/emulator/beam/erl_init.c
index 9ef66456ac..f83e380b02 100644
--- a/erts/emulator/beam/erl_init.c
+++ b/erts/emulator/beam/erl_init.c
@@ -111,6 +111,11 @@ const int etp_lock_check = 1;
 #else
 const int etp_lock_check = 0;
 #endif
+#ifdef WORDS_BIGENDIAN
+const int etp_big_endian = 1;
+#else
+const int etp_big_endian = 0;
+#endif
 /*
  * Note about VxWorks: All variables must be initialized by executable code,
  * not by an initializer. Otherwise a new instance of the emulator will
@@ -123,7 +128,10 @@ extern void ConNormalExit(void);
 extern void ConWaitForExit(void);
 #endif
 
-static void erl_init(int ncpu, int proc_tab_sz);
+static void erl_init(int ncpu,
+		     int proc_tab_sz,
+		     int port_tab_sz,
+		     int port_tab_sz_ignore_files);
 
 static erts_atomic_t exiting;
 
@@ -291,12 +299,18 @@ void
 erts_short_init(void)
 {
     int ncpu = early_init(NULL, NULL);
-    erl_init(ncpu, ERTS_DEFAULT_MAX_PROCESSES);
+    erl_init(ncpu,
+	     ERTS_DEFAULT_MAX_PROCESSES,
+	     ERTS_DEFAULT_MAX_PORTS,
+	     0);
     erts_initialized = 1;
 }
 
 static void
-erl_init(int ncpu, int proc_tab_sz)
+erl_init(int ncpu,
+	 int proc_tab_sz,
+	 int port_tab_sz,
+	 int port_tab_sz_ignore_files)
 {
     init_benchmarking();
 
@@ -333,7 +347,7 @@ erl_init(int ncpu, int proc_tab_sz)
     init_dist();
     erl_drv_thr_init();
     erts_init_async();
-    init_io();
+    erts_init_io(port_tab_sz, port_tab_sz_ignore_files);
     init_copy();
     init_load();
     erts_init_bif();
@@ -556,7 +570,10 @@ void erts_usage(void)
 
     erts_fprintf(stderr, "-P number   set maximum number of processes on this node,\n");
     erts_fprintf(stderr, "            valid range is [%d-%d]\n",
-	       ERTS_MIN_PROCESSES, ERTS_MAX_PROCESSES);
+		 ERTS_MIN_PROCESSES, ERTS_MAX_PROCESSES);
+    erts_fprintf(stderr, "-Q number   set maximum number of ports on this node,\n");
+    erts_fprintf(stderr, "            valid range is [%d-%d]\n",
+		 ERTS_MIN_PORTS, ERTS_MAX_PORTS);
     erts_fprintf(stderr, "-R number   set compatibility release number,\n");
     erts_fprintf(stderr, "            valid range [%d-%d]\n",
 		 this_rel-2, this_rel);
@@ -946,12 +963,13 @@ erl_start(int argc, char **argv)
 {
     int i = 1;
     char* arg=NULL;
-    char* Parg = NULL;
     int have_break_handler = 1;
     char envbuf[21]; /* enough for any 64-bit integer */
     size_t envbufsz;
     int ncpu = early_init(&argc, argv);
     int proc_tab_sz = ERTS_DEFAULT_MAX_PROCESSES;
+    int port_tab_sz = ERTS_DEFAULT_MAX_PORTS;
+    int port_tab_sz_ignore_files = 0;
 
     envbufsz = sizeof(envbuf);
     if (erts_sys_getenv(ERL_MAX_ETS_TABLES_ENV, envbuf, &envbufsz) == 0)
@@ -1210,15 +1228,29 @@ erl_start(int argc, char **argv)
 		       arg);
 	    break;
 
-	case 'P':
-	    /* set maximum number of processes */
-	    Parg = get_arg(argv[i]+2, argv[i+1], &i);
-	    proc_tab_sz = atoi(Parg);
-	    if (proc_tab_sz < ERTS_MIN_PROCESSES
-		|| proc_tab_sz > ERTS_MAX_PROCESSES) {
-		erts_fprintf(stderr, "bad number of processes %s\n", Parg);
+	case 'P': /* set maximum number of processes */
+	    arg = get_arg(argv[i]+2, argv[i+1], &i);
+	    errno = 0;
+	    proc_tab_sz = strtol(arg, NULL, 10);
+	    if (errno != 0
+		|| proc_tab_sz < ERTS_MIN_PROCESSES
+		|| ERTS_MAX_PROCESSES < proc_tab_sz) {
+		erts_fprintf(stderr, "bad number of processes %s\n", arg);
+		erts_usage();
+	    }
+	    break;
+
+	case 'Q': /* set maximum number of ports */
+	    arg = get_arg(argv[i]+2, argv[i+1], &i);
+	    errno = 0;
+	    port_tab_sz = strtol(arg, NULL, 10);
+	    if (errno != 0
+		|| port_tab_sz < ERTS_MIN_PROCESSES
+		|| ERTS_MAX_PROCESSES < port_tab_sz) {
+		erts_fprintf(stderr, "bad number of ports %s\n", arg);
 		erts_usage();
 	    }
+	    port_tab_sz_ignore_files = 1;
 	    break;
 
 	case 'S' : /* Was handled in early_init() just read past it */
@@ -1511,7 +1543,10 @@ erl_start(int argc, char **argv)
     boot_argc = argc - i;  /* Number of arguments to init */
     boot_argv = &argv[i];
 
-    erl_init(ncpu, proc_tab_sz);
+    erl_init(ncpu,
+	     proc_tab_sz,
+	     port_tab_sz,
+	     port_tab_sz_ignore_files);
 
     init_shared_memory(boot_argc, boot_argv);
     load_preloaded();
diff --git a/erts/emulator/beam/erl_node_container_utils.h b/erts/emulator/beam/erl_node_container_utils.h
index 56f658993b..667bda255b 100644
--- a/erts/emulator/beam/erl_node_container_utils.h
+++ b/erts/emulator/beam/erl_node_container_utils.h
@@ -118,8 +118,18 @@
 
 extern ErtsPTab erts_proc;
 
-#define internal_pid_index(x)		erts_ptab_data2ix(&erts_proc, \
-							  internal_pid_data((x)))
+#define make_internal_pid(D)		erts_ptab_make_id(&erts_proc, \
+							  (D), \
+							  _TAG_IMMED1_PID)
+
+#define internal_pid_index(PID)		(ASSERT_EXPR(is_internal_pid((PID))), \
+					 erts_ptab_id2pix(&erts_proc, (PID)))
+
+#define internal_pid_data(PID)		(ASSERT_EXPR(is_internal_pid((PID))), \
+					 erts_ptab_id2data(&erts_proc, (PID)))
+
+#define internal_pid_number(x)		_GET_PID_NUM(internal_pid_data((x)))
+#define internal_pid_serial(x)		_GET_PID_SER(internal_pid_data((x)))
 
 #define internal_pid_node_name(x)	(internal_pid_node((x))->sysname)
 #define external_pid_node_name(x)	(external_pid_node((x))->sysname)
@@ -164,18 +174,14 @@ extern ErtsPTab erts_proc;
  * 32-bit CPU.
  */
 
-#define ERTS_MAX_PROCESSES ((SWORD_CONSTANT(1) << 27)-1)
-#if (ERTS_MAX_PROCESSES > MAX_SMALL)
-# error "The maximum number of processes must fit in a SMALL."
-#endif
-
+#define ERTS_MAX_PROCESSES		(ERTS_PTAB_MAX_SIZE-1)
 #define ERTS_MAX_PID_DATA		((1 << _PID_DATA_SIZE) - 1)
 #define ERTS_MAX_PID_NUMBER		((1 << _PID_NUM_SIZE) - 1)
 #define ERTS_MAX_PID_SERIAL		((1 << _PID_SER_SIZE) - 1)
 
 #define ERTS_PROC_BITS			(_PID_SER_SIZE + _PID_NUM_SIZE)
 
-#define ERTS_INVALID_PID		make_internal_pid(ERTS_MAX_PID_DATA)
+#define ERTS_INVALID_PID		ERTS_PTAB_INVALID_ID(_TAG_IMMED1_PID)
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *\
  * Ports                                                                   *
@@ -183,8 +189,17 @@ extern ErtsPTab erts_proc;
 
 extern ErtsPTab erts_port;
 
-#define internal_port_index(x)		erts_ptab_data2ix(&erts_port, \
-							  internal_port_data((x)))
+#define make_internal_port(D)		erts_ptab_make_id(&erts_port, \
+							  (D), \
+							  _TAG_IMMED1_PORT)
+
+#define internal_port_index(PRT)	(ASSERT_EXPR(is_internal_port((PRT))), \
+					 erts_ptab_id2pix(&erts_port, (PRT)))
+
+#define internal_port_data(PRT)		(ASSERT_EXPR(is_internal_port((PRT))), \
+					 erts_ptab_id2data(&erts_port, (PRT)))
+
+#define internal_port_number(x) _GET_PORT_NUM(internal_port_data((x)))
 
 #define internal_port_node_name(x)	(internal_port_node((x))->sysname)
 #define external_port_node_name(x)	(external_port_node((x))->sysname)
@@ -227,14 +242,13 @@ extern ErtsPTab erts_port;
    which defines the maximum number of simultaneous Ports
    in the Erlang node. ERTS_MAX_PORTS is a hard upper limit.
 */
-#define ERTS_MAX_PORTS			(1 << ERTS_PORTS_BITS)
-
+#define ERTS_MAX_PORTS			(ERTS_PTAB_MAX_SIZE-1)
 #define ERTS_MAX_PORT_DATA		((1 << _PORT_DATA_SIZE) - 1)
 #define ERTS_MAX_PORT_NUMBER		((1 << _PORT_NUM_SIZE) - 1)
 
 #define ERTS_PORTS_BITS			(_PORT_NUM_SIZE)
 
-#define ERTS_INVALID_PORT		make_internal_port(ERTS_MAX_PORT_DATA)
+#define ERTS_INVALID_PORT		ERTS_PTAB_INVALID_ID(_TAG_IMMED1_PORT)
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *\
  * Refs                                                                    *
diff --git a/erts/emulator/beam/erl_port.h b/erts/emulator/beam/erl_port.h
index fb34a6da2d..3de0eed9ea 100644
--- a/erts/emulator/beam/erl_port.h
+++ b/erts/emulator/beam/erl_port.h
@@ -28,6 +28,10 @@ typedef struct _erl_drv_port Port;
 #include "erl_port_task.h"
 #include "erl_ptab.h"
 #include "erl_thr_progress.h"
+#include "erl_trace.h"
+
+#define ERTS_DEFAULT_MAX_PORTS (1 << 16)
+#define ERTS_MIN_PORTS 1024
 
 typedef struct erts_driver_t_ erts_driver_t;
 
diff --git a/erts/emulator/beam/erl_process.h b/erts/emulator/beam/erl_process.h
index f5b7921820..1feb5b96db 100644
--- a/erts/emulator/beam/erl_process.h
+++ b/erts/emulator/beam/erl_process.h
@@ -72,7 +72,7 @@ struct ErtsNodesMonitor_;
 
 #define ERTS_MAX_NO_OF_SCHEDULERS 1024
 
-#define ERTS_DEFAULT_MAX_PROCESSES (1 << 15)
+#define ERTS_DEFAULT_MAX_PROCESSES (1 << 18)
 
 #define ERTS_HEAP_ALLOC(Type, Size)					\
      erts_alloc((Type), (Size))
@@ -1727,10 +1727,10 @@ extern int erts_disable_proc_not_running_opt;
 
 
 /* Minimum NUMBER of processes for a small system to start */
-#ifdef ERTS_SMP
+#define ERTS_MIN_PROCESSES		1024
+#if defined(ERTS_SMP) && ERTS_MIN_PROCESSES < ERTS_NO_OF_PIX_LOCKS
+#undef ERTS_MIN_PROCESSES
 #define ERTS_MIN_PROCESSES		ERTS_NO_OF_PIX_LOCKS
-#else
-#define ERTS_MIN_PROCESSES		16
 #endif
 
 void erts_smp_notify_inc_runq(ErtsRunQueue *runq);
diff --git a/erts/emulator/beam/erl_process_lock.h b/erts/emulator/beam/erl_process_lock.h
index 7ca52303da..537cd3f24f 100644
--- a/erts/emulator/beam/erl_process_lock.h
+++ b/erts/emulator/beam/erl_process_lock.h
@@ -205,7 +205,7 @@ typedef struct erts_proc_lock_t_ {
 					 & ~ERTS_PROC_LOCK_MAIN)
 
 
-#define ERTS_PIX_LOCKS_BITS		8
+#define ERTS_PIX_LOCKS_BITS		10
 #define ERTS_NO_OF_PIX_LOCKS		(1 << ERTS_PIX_LOCKS_BITS)
 
 
diff --git a/erts/emulator/beam/erl_ptab.c b/erts/emulator/beam/erl_ptab.c
index eba0c286cc..7ab756ae8d 100644
--- a/erts/emulator/beam/erl_ptab.c
+++ b/erts/emulator/beam/erl_ptab.c
@@ -429,7 +429,7 @@ erts_ptab_init_table(ErtsPTab *ptab,
 		     char *name)
 {
     size_t tab_sz;
-    int max_data_bits;
+    int bits;
     char *tab_end;
     erts_smp_atomic_t *tab_entry;
     erts_smp_rwmtx_opt_t rwmtx_opts = ERTS_SMP_RWMTX_OPT_DEFAULT_INITER;
@@ -440,8 +440,13 @@ erts_ptab_init_table(ErtsPTab *ptab,
     erts_smp_atomic32_init_nob(&ptab->vola.tile.count, 0);
     last_data_init_nob(ptab, ~((Uint64) 0));
 
-    if (size > (1 << ERTS_PROC_BITS))
-	size = 1 << ERTS_PROC_BITS;
+    /* A size that is a power of 2 is to prefer performance wise */
+    bits = erts_fit_in_bits_int32(size-1);
+    size = 1 << bits;
+    if (size > ERTS_PTAB_MAX_SIZE) {
+	size = ERTS_PTAB_MAX_SIZE;
+	bits = erts_fit_in_bits_int32((Sint32) size - 1);
+    }
 
     ptab->r.o.max = size;
 
@@ -454,34 +459,31 @@ erts_ptab_init_table(ErtsPTab *ptab,
 	tab_entry++;
     }
 
-    max_data_bits = erts_fit_in_bits_int32((Sint32) ptab->r.o.max - 1);
-
     ptab->r.o.tab_cache_lines = tab_sz/ERTS_CACHE_LINE_SIZE;
     ptab->r.o.pix_per_cache_line = (ERTS_CACHE_LINE_SIZE
 				    / sizeof(erts_smp_atomic_t));
-    if ((ptab->r.o.max & (ptab->r.o.max - 1))
-	| (ptab->r.o.pix_per_cache_line & (ptab->r.o.pix_per_cache_line - 1))) {
-	/* ptab->r.o.max or ptab->r.o.pix_per_cache_line not a power of 2 :-( */
-	ptab->r.o.pix_cl_mask = 0;
-	ptab->r.o.pix_cl_shift = 0;
-	ptab->r.o.pix_cli_mask = 0;
-	ptab->r.o.pix_cli_shift = 0;
-    }
-    else {
-	ASSERT((ptab->r.o.tab_cache_lines
-		& (ptab->r.o.tab_cache_lines - 1)) == 0);
-	ptab->r.o.pix_cl_mask
-	    = ptab->r.o.tab_cache_lines-1;
-	ptab->r.o.pix_cl_shift
-	    = erts_fit_in_bits_int32(ptab->r.o.pix_per_cache_line-1);
-	ptab->r.o.pix_cli_shift
-	    = erts_fit_in_bits_int32(ptab->r.o.pix_cl_mask);
-	ptab->r.o.pix_cli_mask
-	    = (1 << (max_data_bits - ptab->r.o.pix_cli_shift)) - 1;
-    }
+    ASSERT((ptab->r.o.max & (ptab->r.o.max - 1)) == 0); /* power of 2 */
+    ASSERT((ptab->r.o.pix_per_cache_line
+	    & (ptab->r.o.pix_per_cache_line - 1)) == 0); /* power of 2 */
+    ASSERT((ptab->r.o.tab_cache_lines
+	    & (ptab->r.o.tab_cache_lines - 1)) == 0); /* power of 2 */
+
+    ptab->r.o.pix_mask
+	= (1 << bits) - 1;
+    ptab->r.o.pix_cl_mask
+	= ptab->r.o.tab_cache_lines-1;
+    ptab->r.o.pix_cl_shift
+	= erts_fit_in_bits_int32(ptab->r.o.pix_per_cache_line-1);
+    ptab->r.o.pix_cli_shift
+	= erts_fit_in_bits_int32(ptab->r.o.pix_cl_mask);
+    ptab->r.o.pix_cli_mask
+	= (1 << (bits - ptab->r.o.pix_cli_shift)) - 1;
+
+    ASSERT(ptab->r.o.pix_cl_shift + ptab->r.o.pix_cli_shift == bits);
 
     ptab->r.o.invalid_element = invalid_element;
-    ptab->r.o.invalid_data = ERTS_PTAB_ID2DATA(invalid_element->id);
+    ptab->r.o.invalid_data = erts_ptab_id2data(ptab, invalid_element->id);
+    ptab->r.o.release_element = release_element;
     if (release_element)
 	ptab->r.o.release_element = release_element;
     else
@@ -493,6 +495,26 @@ erts_ptab_init_table(ErtsPTab *ptab,
     ptab->list.data.chunks = (((ptab->r.o.max - 1)
 			       / ERTS_PTAB_LIST_BIF_TAB_CHUNK_SIZE)
 			      + 1);
+
+    if (size == ERTS_PTAB_MAX_SIZE) {
+	int pix;
+	/*
+	 * We want a table size of a power of 2 which ERTS_PTAB_MAX_SIZE
+	 * is. We only have ERTS_PTAB_MAX_SIZE-1 unique identifiers and
+	 * we don't want to shrink the size to ERTS_PTAB_MAX_SIZE/2.
+	 *
+	 * In order to fix this, we insert a pointer from the table
+	 * to the invalid_element, wich will be interpreted as a
+	 * slot currently being modified. This way we will be able to
+	 * have ERTS_PTAB_MAX_SIZE-1 valid elements in the table while
+	 * still having a table size of the power of 2.
+	 */
+	erts_smp_atomic32_inc_nob(&ptab->vola.tile.count);
+	pix = erts_ptab_data2pix(ptab, ptab->r.o.invalid_data);
+	erts_smp_atomic_set_relb(&ptab->r.o.tab[pix],
+				 (erts_aint_t) ptab->r.o.invalid_element);
+    }
+
 }
 
 int
@@ -541,7 +563,7 @@ erts_ptab_new_element(ErtsPTab *ptab,
     /* Reserve slot */
     while (1) {
 	ld++;
-	pix = erts_ptab_data2ix(ptab, ERTS_PTAB_LastData2EtermData(ld));
+	pix = erts_ptab_data2pix(ptab, ERTS_PTAB_LastData2EtermData(ld));
 	if (erts_smp_atomic_read_nob(&ptab->r.o.tab[pix]) == ERTS_AINT_NULL) {
 	    erts_aint_t val;
 	    val = erts_smp_atomic_cmpxchg_relb(&ptab->r.o.tab[pix],
@@ -558,8 +580,8 @@ erts_ptab_new_element(ErtsPTab *ptab,
     if (data == ptab->r.o.invalid_data) {
 	/* Do not use invalid data; fix it... */
 	ld += ptab->r.o.max;
-	ASSERT(pix == erts_ptab_data2ix(ptab,
-					ERTS_PTAB_LastData2EtermData(ld)));
+	ASSERT(pix == erts_ptab_data2pix(ptab,
+					 ERTS_PTAB_LastData2EtermData(ld)));
 	data = ERTS_PTAB_LastData2EtermData(ld);
 	ASSERT(data != ptab->r.o.invalid_data);
     }
@@ -609,7 +631,7 @@ save_deleted_element(ErtsPTab *ptab, ErtsPTabElementCommon *ptab_el)
 
     ptdep->prev = ptab->list.data.deleted.end;
     ptdep->next = NULL;
-    ptdep->ix = erts_ptab_data2ix(ptab, ERTS_PTAB_ID2DATA(ptab_el->id));
+    ptdep->ix = erts_ptab_id2pix(ptab, ptab_el->id);
     ptdep->u.element.id = ptab_el->id;
     ptdep->u.element.inserted = ptab_el->u.alive.started_interval;
     ptdep->u.element.deleted =
@@ -632,7 +654,7 @@ erts_ptab_delete_element(ErtsPTab *ptab,
 			 ErtsPTabElementCommon *ptab_el)
 {
     int maybe_save;
-    int pix = erts_ptab_data2ix(ptab, ERTS_PTAB_ID2DATA(ptab_el->id));
+    int pix = erts_ptab_id2pix(ptab, ptab_el->id);
 
     ASSERT(erts_get_scheduler_id()); /* *Need* to be a scheduler */
 
@@ -1274,9 +1296,9 @@ erts_ptab_test_next_id(ErtsPTab *ptab, int set, Uint next)
 	data = ERTS_PTAB_LastData2EtermData(ld);
 	if (ptab->r.o.invalid_data == data) {
 	    ld += ptab->r.o.max;
-	    ASSERT(erts_ptab_data2ix(ptab, data)
-		   == erts_ptab_data2ix(ptab,
-					ERTS_PTAB_LastData2EtermData(ld)));
+	    ASSERT(erts_ptab_data2pix(ptab, data)
+		   == erts_ptab_data2pix(ptab,
+					 ERTS_PTAB_LastData2EtermData(ld)));
 	}
 	last_data_set_relb(ptab, ld);
     }
@@ -1295,9 +1317,9 @@ erts_ptab_test_next_id(ErtsPTab *ptab, int set, Uint next)
 	    data = ERTS_PTAB_LastData2EtermData(ld);
 	    if (ptab->r.o.invalid_data == data) {
 		ld += ptab->r.o.max;
-		ASSERT(erts_ptab_data2ix(ptab, data)
-		       == erts_ptab_data2ix(ptab,
-					    ERTS_PTAB_LastData2EtermData(ld)));
+		ASSERT(erts_ptab_data2pix(ptab, data)
+		       == erts_ptab_data2pix(ptab,
+					     ERTS_PTAB_LastData2EtermData(ld)));
 		data = ERTS_PTAB_LastData2EtermData(ld);
 	    }
 	    res = data;
@@ -1510,10 +1532,9 @@ debug_ptab_list_check_del_list(ErtsPTab *ptab)
 		prev_x_interval_p = &ptdep->u.element.deleted;
 		ERTS_PTAB_LIST_ASSERT(
 		    erts_ptab_is_valid_id(ptdep->u.element.id));
-		ERTS_PTAB_LIST_ASSERT(
-		    erts_ptab_data2ix(ptab,
-				      ERTS_PTAB_ID2DATA(ptdep->u.element.id))
-		    == ptdep->ix);
+		ERTS_PTAB_LIST_ASSERT(erts_ptab_id2pix(ptab,
+						       ptdep->u.element.id)
+				      == ptdep->ix);
 
 	    }
 	}
diff --git a/erts/emulator/beam/erl_ptab.h b/erts/emulator/beam/erl_ptab.h
index b2ae829d62..8a130f42a3 100644
--- a/erts/emulator/beam/erl_ptab.h
+++ b/erts/emulator/beam/erl_ptab.h
@@ -98,13 +98,14 @@ typedef struct {
 
 typedef struct {
     erts_smp_atomic_t *tab;
-    int max;
-    int tab_cache_lines;
-    int pix_per_cache_line;
-    int pix_cl_mask;
-    int pix_cl_shift;
-    int pix_cli_mask;
-    int pix_cli_shift;
+    Uint32 max;
+    Uint32 tab_cache_lines;
+    Uint32 pix_per_cache_line;
+    Uint32 pix_mask;
+    Uint32 pix_cl_mask;
+    Uint32 pix_cl_shift;
+    Uint32 pix_cli_mask;
+    Uint32 pix_cli_shift;
     ErtsPTabElementCommon *invalid_element;
     Eterm invalid_data;
     void (*release_element)(void *);
@@ -139,6 +140,12 @@ typedef struct {
 
 #define ERTS_PTAB_ID_DATA_SIZE	28
 #define ERTS_PTAB_ID_DATA_SHIFT	(_TAG_IMMED1_SIZE)
+/* ERTS_PTAB_MAX_SIZE must be a power of 2 */
+#define ERTS_PTAB_MAX_SIZE (SWORD_CONSTANT(1) << 27)
+#if (ERTS_PTAB_MAX_SIZE-1) > MAX_SMALL
+# error "The maximum number of processes/ports must fit in a SMALL."
+#endif
+
 
 /*
  * Currently pids and ports are allowed.
@@ -156,14 +163,14 @@ typedef struct {
 # error "Unexpected port tag size"
 #endif
 
+#define ERTS_PTAB_INVALID_ID(TAG)					\
+    ((Eterm)								\
+     ((((1 << ERTS_PTAB_ID_DATA_SIZE) - 1) << ERTS_PTAB_ID_DATA_SHIFT)	\
+      | (TAG)))
+
 #define erts_ptab_is_valid_id(ID)					\
     (is_internal_pid((ID)) || is_internal_port((ID)))
 
-#define ERTS_PTAB_ID2DATA(ID)						\
-    (ASSERT_EXPR(erts_ptab_is_valid_id((ID))),				\
-     (((ID) >> ERTS_PTAB_ID_DATA_SHIFT)					\
-      & ~(~((Uint) 0) << ERTS_PTAB_ID_DATA_SIZE)))
-
 void erts_ptab_init(void);
 void erts_ptab_init_table(ErtsPTab *ptab,
 			  ErtsAlcType_t atype,
@@ -182,7 +189,13 @@ int erts_ptab_initialized(ErtsPTab *ptab);
 ERTS_GLB_INLINE erts_interval_t *erts_ptab_interval(ErtsPTab *ptab);
 ERTS_GLB_INLINE int erts_ptab_max(ErtsPTab *ptab);
 ERTS_GLB_INLINE int erts_ptab_count(ErtsPTab *ptab);
-ERTS_GLB_INLINE int erts_ptab_data2ix(ErtsPTab *ptab, Eterm data);
+ERTS_GLB_INLINE Uint erts_ptab_pixdata2data(ErtsPTab *ptab, Eterm pixdata);
+ERTS_GLB_INLINE Uint32 erts_ptab_pixdata2pix(ErtsPTab *ptab, Eterm pixdata);
+ERTS_GLB_INLINE Uint32 erts_ptab_data2pix(ErtsPTab *ptab, Eterm data);
+ERTS_GLB_INLINE Uint erts_ptab_data2pixdata(ErtsPTab *ptab, Eterm data);
+ERTS_GLB_INLINE Eterm erts_ptab_make_id(ErtsPTab *ptab, Eterm data, Eterm tag);
+ERTS_GLB_INLINE int erts_ptab_id2pix(ErtsPTab *ptab, Eterm id);
+ERTS_GLB_INLINE Uint erts_ptab_id2data(ErtsPTab *ptab, Eterm id);
 ERTS_GLB_INLINE erts_aint_t erts_ptab_pix2intptr_nob(ErtsPTab *ptab, int ix);
 ERTS_GLB_INLINE erts_aint_t erts_ptab_pix2intptr_ddrb(ErtsPTab *ptab, int ix);
 ERTS_GLB_INLINE erts_aint_t erts_ptab_pix2intptr_rb(ErtsPTab *ptab, int ix);
@@ -211,39 +224,118 @@ erts_ptab_interval(ErtsPTab *ptab)
 ERTS_GLB_INLINE int
 erts_ptab_max(ErtsPTab *ptab)
 {
-    return ptab->r.o.max;
+    int max = ptab->r.o.max;
+    return max == ERTS_PTAB_MAX_SIZE ? max - 1 : max;
 }
 
 ERTS_GLB_INLINE int
 erts_ptab_count(ErtsPTab *ptab)
 {
+    int max = ptab->r.o.max;
     erts_aint32_t res = erts_smp_atomic32_read_nob(&ptab->vola.tile.count);
-    if (res > ptab->r.o.max)
-	return ptab->r.o.max;
+    if (max == ERTS_PTAB_MAX_SIZE) {
+	max--;
+	res--;
+    }
+    if (res > max)
+	return max;
     ASSERT(res >= 0);
     return (int) res;
 
 }
 
-ERTS_GLB_INLINE int erts_ptab_data2ix(ErtsPTab *ptab, Eterm data)
+ERTS_GLB_INLINE Uint erts_ptab_pixdata2data(ErtsPTab *ptab, Eterm pixdata)
 {
-    int n, pix;
+    Uint32 data = ((Uint32) pixdata) & ~ptab->r.o.pix_mask;
+    data |= (pixdata >> ptab->r.o.pix_cl_shift) & ptab->r.o.pix_cl_mask;
+    data |= (pixdata & ptab->r.o.pix_cli_mask) << ptab->r.o.pix_cli_shift;
+    return data;
+}
 
-    n = (int) data;
-    if (ptab->r.o.pix_cl_mask) {
-	pix = ((n & ptab->r.o.pix_cl_mask) << ptab->r.o.pix_cl_shift);
-	pix += ((n >> ptab->r.o.pix_cli_shift) & ptab->r.o.pix_cli_mask);
-    }
-    else {
-	n %= ptab->r.o.max;
-	pix = n % ptab->r.o.tab_cache_lines;
-	pix *= ptab->r.o.pix_per_cache_line;
-	pix += n / ptab->r.o.tab_cache_lines;
-    }
+ERTS_GLB_INLINE Uint32 erts_ptab_pixdata2pix(ErtsPTab *ptab, Eterm pixdata)
+{
+    return ((Uint32) pixdata) & ptab->r.o.pix_mask;
+}
+
+ERTS_GLB_INLINE Uint32 erts_ptab_data2pix(ErtsPTab *ptab, Eterm data)
+{
+    Uint32 n, pix;
+    n = (Uint32) data;
+    pix = ((n & ptab->r.o.pix_cl_mask) << ptab->r.o.pix_cl_shift);
+    pix += ((n >> ptab->r.o.pix_cli_shift) & ptab->r.o.pix_cli_mask);
     ASSERT(0 <= pix && pix < ptab->r.o.max);
     return pix;
 }
 
+ERTS_GLB_INLINE Uint erts_ptab_data2pixdata(ErtsPTab *ptab, Eterm data)
+{
+    Uint pixdata = data & ~((Uint) ptab->r.o.pix_mask);
+    pixdata |= (Uint) erts_ptab_data2pix(ptab, data);
+    ASSERT(data == erts_ptab_pixdata2data(ptab, pixdata));
+    return pixdata;
+}
+
+#if ERTS_SIZEOF_TERM == 8
+
+ERTS_GLB_INLINE Eterm
+erts_ptab_make_id(ErtsPTab *ptab, Eterm data, Eterm tag)
+{
+    HUint huint;
+    Uint32 low_data = (Uint32) data;
+    low_data &= (1 << ERTS_PTAB_ID_DATA_SIZE) - 1;
+    low_data <<= ERTS_PTAB_ID_DATA_SHIFT;
+    huint.hval[ERTS_HUINT_HVAL_HIGH] = erts_ptab_data2pix(ptab, data);
+    huint.hval[ERTS_HUINT_HVAL_LOW] = low_data | ((Uint32) tag);
+    return (Eterm) huint.val;
+}
+
+ERTS_GLB_INLINE int
+erts_ptab_id2pix(ErtsPTab *ptab, Eterm id)
+{
+    HUint huint;
+    huint.val = id;
+    return (int) huint.hval[ERTS_HUINT_HVAL_HIGH];
+}
+
+ERTS_GLB_INLINE Uint
+erts_ptab_id2data(ErtsPTab *ptab, Eterm id)
+{
+    HUint huint;
+    huint.val = id;
+    return (Uint) (huint.hval[ERTS_HUINT_HVAL_LOW] >> ERTS_PTAB_ID_DATA_SHIFT);
+}
+
+#elif ERTS_SIZEOF_TERM == 4
+
+ERTS_GLB_INLINE Eterm
+erts_ptab_make_id(ErtsPTab *ptab, Eterm data, Eterm tag)
+{
+    Eterm id;
+    data &= ((1 << ERTS_PTAB_ID_DATA_SIZE) - 1);
+    id = (Eterm) erts_ptab_data2pixdata(ptab, data);
+    return (id << ERTS_PTAB_ID_DATA_SHIFT) | tag;
+}
+
+ERTS_GLB_INLINE int
+erts_ptab_id2pix(ErtsPTab *ptab, Eterm id)
+{
+    Uint pixdata = (Uint) id;
+    pixdata >>= ERTS_PTAB_ID_DATA_SHIFT;
+    return (int) erts_ptab_pixdata2pix(ptab, pixdata);
+}
+
+ERTS_GLB_INLINE Uint
+erts_ptab_id2data(ErtsPTab *ptab, Eterm id)
+{
+    Uint pixdata = (Uint) id;
+    pixdata >>= ERTS_PTAB_ID_DATA_SHIFT;
+    return erts_ptab_pixdata2data(ptab, pixdata);
+}
+
+#else
+#error "Unsupported size of term"
+#endif
+
 ERTS_GLB_INLINE erts_aint_t erts_ptab_pix2intptr_nob(ErtsPTab *ptab, int ix)
 {
     ASSERT(0 <= ix && ix < ptab->r.o.max);
diff --git a/erts/emulator/beam/erl_term.c b/erts/emulator/beam/erl_term.c
index f77e8b798f..b86e3e16ca 100644
--- a/erts/emulator/beam/erl_term.c
+++ b/erts/emulator/beam/erl_term.c
@@ -144,9 +144,7 @@ ET_DEFINE_CHECKED(Uint,bignum_header_arity,Eterm,_is_bignum_header);
 ET_DEFINE_CHECKED(Eterm*,big_val,Wterm,is_big);
 ET_DEFINE_CHECKED(Eterm*,float_val,Wterm,is_float);
 ET_DEFINE_CHECKED(Eterm*,tuple_val,Wterm,is_tuple);
-ET_DEFINE_CHECKED(Uint,internal_pid_data,Eterm,is_internal_pid);
 ET_DEFINE_CHECKED(struct erl_node_*,internal_pid_node,Eterm,is_internal_pid);
-ET_DEFINE_CHECKED(Uint,internal_port_data,Eterm,is_internal_port);
 ET_DEFINE_CHECKED(struct erl_node_*,internal_port_node,Eterm,is_internal_port);
 ET_DEFINE_CHECKED(Eterm*,internal_ref_val,Wterm,is_internal_ref);
 ET_DEFINE_CHECKED(Uint,internal_ref_data_words,Wterm,is_internal_ref);
diff --git a/erts/emulator/beam/erl_term.h b/erts/emulator/beam/erl_term.h
index 7349d3e0c7..bc4c3a09a0 100644
--- a/erts/emulator/beam/erl_term.h
+++ b/erts/emulator/beam/erl_term.h
@@ -591,23 +591,13 @@ _ET_DECLARE_CHECKED(Eterm*,tuple_val,Wterm)
 #define make_pid_data(Ser, Num) \
   ((Uint) ((Ser) << _PID_NUM_SIZE | (Num)))
 
-#define make_internal_pid(X) \
-  ((Eterm) (((X) << _PID_DATA_SHIFT) | _TAG_IMMED1_PID))
-
 #define is_internal_pid(x)	(((x) & _TAG_IMMED1_MASK) == _TAG_IMMED1_PID)
 #define is_not_internal_pid(x)	(!is_internal_pid((x)))
 
-#define _unchecked_internal_pid_data(x) _GET_PID_DATA((x))
-_ET_DECLARE_CHECKED(Uint,internal_pid_data,Eterm)
-#define internal_pid_data(x) _ET_APPLY(internal_pid_data,(x))
-
 #define _unchecked_internal_pid_node(x) erts_this_node
 _ET_DECLARE_CHECKED(struct erl_node_*,internal_pid_node,Eterm)
 #define internal_pid_node(x) _ET_APPLY(internal_pid_node,(x))
 
-#define internal_pid_number(x) _GET_PID_NUM(internal_pid_data((x)))
-#define internal_pid_serial(x) _GET_PID_SER(internal_pid_data((x)))
-
 #define internal_pid_data_words(x) (1)
 
 /* 
@@ -646,18 +636,9 @@ _ET_DECLARE_CHECKED(struct erl_node_*,internal_pid_node,Eterm)
 #define _GET_PORT_NUM(X)	_GETBITS((X), 0, _PORT_NUM_SIZE)
 
 
-#define make_internal_port(X) \
-  ((Eterm) (((X) << _PORT_DATA_SHIFT) | _TAG_IMMED1_PORT))
-
 #define is_internal_port(x)	(((x) & _TAG_IMMED1_MASK) == _TAG_IMMED1_PORT)
 #define is_not_internal_port(x)	(!is_internal_port(x))
 
-#define _unchecked_internal_port_data(x) _GET_PORT_DATA((x))
-_ET_DECLARE_CHECKED(Uint,internal_port_data,Eterm)
-#define internal_port_data(x) _ET_APPLY(internal_port_data,(x))
-
-#define internal_port_number(x) _GET_PORT_NUM(internal_port_data((x)))
-
 #define _unchecked_internal_port_node(x) erts_this_node
 _ET_DECLARE_CHECKED(struct erl_node_*,internal_port_node,Eterm)
 #define internal_port_node(x) _ET_APPLY(internal_port_node,(x))
diff --git a/erts/emulator/beam/global.h b/erts/emulator/beam/global.h
index ae31ab54b5..0de11afee9 100644
--- a/erts/emulator/beam/global.h
+++ b/erts/emulator/beam/global.h
@@ -899,7 +899,7 @@ void erts_wake_process_later(Port*, Process*);
 Port *erts_open_driver(erts_driver_t*, Eterm, char*, SysDriverOpts*, int *, int *);
 int erts_is_port_ioq_empty(Port *);
 void erts_terminate_port(Port *);
-void init_io(void);
+void erts_init_io(int, int);
 void erts_do_exit_port(Port *, Eterm, Eterm);
 void erts_port_command(Process *, Eterm, Port *, Eterm);
 Eterm erts_port_control(Process*, Port*, Uint, Eterm);
diff --git a/erts/emulator/beam/io.c b/erts/emulator/beam/io.c
index 21fc76b8db..1177e7e691 100644
--- a/erts/emulator/beam/io.c
+++ b/erts/emulator/beam/io.c
@@ -1238,13 +1238,10 @@ release_port(void *vport)
 }
 #endif
 
-/* initialize the port array */
-void init_io(void)
+void erts_init_io(int port_tab_size,
+		  int port_tab_size_ignore_files)
 {
     ErlDrvEntry** dp;
-    char maxports[21]; /* enough for any 64-bit integer */
-    size_t maxportssize = sizeof(maxports);
-    int port_tab_size;
 
 #ifdef ERTS_SMP
     init_xports_list_alloc();
@@ -1252,15 +1249,16 @@ void init_io(void)
 
     pdl_init();
 
-    if (erts_sys_getenv("ERL_MAX_PORTS", maxports, &maxportssize) == 0) 
-	port_tab_size = atoi(maxports);
-    else
-	port_tab_size = sys_max_files();
+    if (!port_tab_size_ignore_files) {
+	int max_files = sys_max_files();
+	if (port_tab_size < max_files)
+	    port_tab_size = max_files;
+    }
 
     if (port_tab_size > ERTS_MAX_PORTS)
 	port_tab_size = ERTS_MAX_PORTS;
-    if (port_tab_size < 1024)
-	port_tab_size = 1024;
+    else if (port_tab_size < ERTS_MIN_PORTS)
+	port_tab_size = ERTS_MIN_PORTS;
 
     erts_smp_mtx_init(&erts_driver_list_lock,"driver_list");
     driver_list = NULL;
diff --git a/erts/emulator/beam/sys.h b/erts/emulator/beam/sys.h
index 0d3b910278..12313f0984 100644
--- a/erts/emulator/beam/sys.h
+++ b/erts/emulator/beam/sys.h
@@ -244,9 +244,11 @@ int real_printf(const char *fmt, ...);
 #if SIZEOF_VOID_P == 8
 #undef  ARCH_32
 #define ARCH_64
+#define ERTS_SIZEOF_TERM 8
 #elif SIZEOF_VOID_P == 4
 #define ARCH_32
 #undef  ARCH_64
+#define ERTS_SIZEOF_TERM 4
 #else
 #error Neither 32 nor 64 bit architecture
 #endif
@@ -254,6 +256,8 @@ int real_printf(const char *fmt, ...);
 #    define HALFWORD_HEAP 1
 #    define HALFWORD_ASSERT 0
 #    define ASSERT_HALFWORD(COND) ASSERT(COND)
+#    undef ERTS_SIZEOF_TERM
+#    define ERTS_SIZEOF_TERM 4
 #else
 #    define HALFWORD_HEAP 0
 #    define HALFWORD_ASSERT 0
@@ -380,6 +384,27 @@ typedef unsigned char byte;
 #error 64-bit architecture, but no appropriate type to use for Uint64 and Sint64 found 
 #endif
 
+#ifdef WORDS_BIGENDIAN
+#  define ERTS_HUINT_HVAL_HIGH 0
+#  define ERTS_HUINT_HVAL_LOW 1
+#else
+#  define ERTS_HUINT_HVAL_HIGH 1
+#  define ERTS_HUINT_HVAL_LOW 0
+#endif
+#if ERTS_SIZEOF_TERM == 8
+typedef union {
+    Uint val;
+    Uint32 hval[2];
+} HUint;
+#elif ERTS_SIZEOF_TERM == 4
+typedef union {
+    Uint val;
+    Uint16 hval[2];
+} HUint;
+#else
+#error "Unsupported size of term"
+#endif
+
 #  define ERTS_EXTRA_DATA_ALIGN_SZ(X) \
     (((size_t) 8) - (((size_t) (X)) & ((size_t) 7)))
 
diff --git a/erts/emulator/test/process_SUITE.erl b/erts/emulator/test/process_SUITE.erl
index 157589d1a4..cd13d8a81d 100644
--- a/erts/emulator/test/process_SUITE.erl
+++ b/erts/emulator/test/process_SUITE.erl
@@ -1468,14 +1468,14 @@ processes_small_tab(doc) ->
 processes_small_tab(suite) ->
     [];
 processes_small_tab(Config) when is_list(Config) ->
-    ?line {ok, SmallNode} = start_node(Config, "+P 500"),
+    ?line {ok, SmallNode} = start_node(Config, "+P 1024"),
     ?line Res = rpc:call(SmallNode, ?MODULE, processes_bif_test, []),
     ?line PBInfo = rpc:call(SmallNode,
 			    erts_debug,
 			    get_internal_state,
 			    [processes_bif_info]),
     ?line stop_node(SmallNode),
-    ?line 1 = PBInfo#ptab_list_bif_info.tab_chunks,
+    ?line true = PBInfo#ptab_list_bif_info.tab_chunks < 10,
     ?line chk_processes_bif_test_res(Res).
 
 processes_this_tab(doc) ->
@@ -1589,8 +1589,8 @@ processes_bif_test() ->
     ?line print_processes_bif_info(PBInfo),
     ?line WantReds = PBInfo#ptab_list_bif_info.min_start_reds + 10,
     ?line WillTrap = case PBInfo of
-			#ptab_list_bif_info{tab_chunks = 1} ->
-			    false;
+			#ptab_list_bif_info{tab_chunks = Chunks} when Chunks < 10 ->
+			    false; %% Skip for small tables
 			#ptab_list_bif_info{tab_chunks = Chunks,
 					    tab_chunks_size = ChunksSize,
 					    tab_indices_per_red = IndiciesPerRed
@@ -1793,7 +1793,7 @@ do_processes_bif_die_test(N, Processes) ->
     catch
 	throw:{kill_in_trap, R} when N > 0 ->
 	    ?t:format("Failed to kill in trap: ~p~n", [R]),
-	    ?t:format("Trying again~p~n", []),
+	    ?t:format("Trying again~n", []),
 	    do_processes_bif_die_test(N-1, Processes)
     end.
 	    
diff --git a/erts/etc/common/erlexec.c b/erts/etc/common/erlexec.c
index 19b3bb82ef..7805530b50 100644
--- a/erts/etc/common/erlexec.c
+++ b/erts/etc/common/erlexec.c
@@ -814,6 +814,7 @@ int main(int argc, char **argv)
 		  case 'b':
 		  case 'i':
 		  case 'P':
+		  case 'Q':
 		  case 'S':
 		  case 't':
 		  case 'T':
@@ -1121,7 +1122,8 @@ usage_aux(void)
 	  "[-make] [-man [manopts] MANPAGE] [-x] [-emu_args] "
 	  "[-args_file FILENAME] [+A THREADS] [+a SIZE] [+B[c|d|i]] [+c] "
 	  "[+h HEAP_SIZE_OPTION] [+K BOOLEAN] "
-	  "[+l] [+M<SUBSWITCH> <ARGUMENT>] [+P MAX_PROCS] [+R COMPAT_REL] "
+	  "[+l] [+M<SUBSWITCH> <ARGUMENT>] [+P MAX_PROCS] [+Q MAX_PORTS] "
+	  "[+R COMPAT_REL] "
 	  "[+r] [+rg READER_GROUPS_LIMIT] [+s SCHEDULER_OPTION] "
 	  "[+S NO_SCHEDULERS:NO_SCHEDULERS_ONLINE] [+T LEVEL] [+V] [+v] "
 	  "[+W<i|w>] [+z MISC_OPTION] [args ...]\n");
diff --git a/system/doc/efficiency_guide/advanced.xml b/system/doc/efficiency_guide/advanced.xml
index 821175bb09..ac35a37bc4 100644
--- a/system/doc/efficiency_guide/advanced.xml
+++ b/system/doc/efficiency_guide/advanced.xml
@@ -123,12 +123,11 @@ On 64-bit architectures: 4 words for a reference from the current local node, an
       <tag><em>Processes</em></tag>
       <item>
         <p>The maximum number of simultaneously alive Erlang processes is
-          by default 32768. This limit can be raised up to at most 268435456
-          processes at startup (see documentation of the system flag
-          <seealso marker="erts:erl#max_processes">+P</seealso> in the
-          <seealso marker="erts:erl">erl(1)</seealso> documentation).
-          The maximum limit of 268435456 processes will at least on a 32-bit
-          architecture be impossible to reach due to memory shortage.</p>
+          by default 32768. This limit can be configured at startup,
+	  for more information see the
+	  <seealso marker="erts:erl#max_processes"><c>+P</c></seealso>
+	  command line flag of
+	  <seealso marker="erts:erl"><c>erl(1)</c></seealso>.</p>
       </item>
       <tag><em>Distributed nodes</em></tag>
       <item>
@@ -184,13 +183,12 @@ On 64-bit architectures: 4 words for a reference from the current local node, an
       <tag><em>Open ports</em></tag>
       <item>
         <marker id="ports"></marker>
-        <p>The maximum number of simultaneously open Erlang ports is
-          by default 1024. This limit can be raised up to at most 268435456
-          at startup (see environment variable
-          <seealso marker="erts:erlang#ERL_MAX_PORTS">ERL_MAX_PORTS</seealso>
-          in <seealso marker="erts:erlang">erlang(3)</seealso>)
-          The maximum limit of 268435456 open ports will at least on a 32-bit
-          architecture be impossible to reach due to memory shortage.</p>
+	  <p>The maximum number of simultaneously oper Erlang ports is
+	  often by default 16384. This limit can be configured at startup,
+	  for more information see the
+	  <seealso marker="erts:erl#max_ports"><c>+Q</c></seealso>
+	  command line flag of
+	  <seealso marker="erts:erl"><c>erl(1)</c></seealso>.</p>
       </item>
       <tag><em>Open files, and sockets</em></tag>
       <item>      <marker id="files_sockets"></marker>