changeset 51227:50eb2c0f252b

8189922: UseNUMA memory interleaving vs membind Reviewed-by: gromero, drwhite, dholmes, tschatzl Contributed-by: Swati Sharma <swatibits14@gmail.com>
author gromero
date Thu, 19 Jul 2018 16:56:05 -0400
parents dd1aa4229fd4
children d9b22cbe3e7a
files src/hotspot/os/linux/os_linux.cpp src/hotspot/os/linux/os_linux.hpp
diffstat 2 files changed, 61 insertions(+), 12 deletions(-) [+]
line wrap: on
line diff
--- a/src/hotspot/os/linux/os_linux.cpp	Sun Jul 22 20:00:39 2018 -0700
+++ b/src/hotspot/os/linux/os_linux.cpp	Thu Jul 19 16:56:05 2018 -0400
@@ -2841,9 +2841,10 @@
 
   // Map all node ids in which it is possible to allocate memory. Also nodes are
   // not always consecutively available, i.e. available from 0 to the highest
-  // node number.
+  // node number. If the nodes have been bound explicitly using numactl membind,
+  // then allocate memory from those nodes only.
   for (int node = 0; node <= highest_node_number; node++) {
-    if (Linux::isnode_in_configured_nodes((unsigned int)node)) {
+    if (Linux::isnode_in_bound_nodes((unsigned int)node)) {
       ids[i++] = node;
     }
   }
@@ -2944,6 +2945,8 @@
                                                libnuma_dlsym(handle, "numa_bitmask_isbitset")));
       set_numa_distance(CAST_TO_FN_PTR(numa_distance_func_t,
                                        libnuma_dlsym(handle, "numa_distance")));
+      set_numa_get_membind(CAST_TO_FN_PTR(numa_get_membind_func_t,
+                                          libnuma_v2_dlsym(handle, "numa_get_membind")));
 
       if (numa_available() != -1) {
         set_numa_all_nodes((unsigned long*)libnuma_dlsym(handle, "numa_all_nodes"));
@@ -3008,17 +3011,23 @@
   unsigned long *cpu_map = NEW_C_HEAP_ARRAY(unsigned long, cpu_map_size, mtInternal);
   for (size_t i = 0; i < node_num; i++) {
     // Check if node is configured (not a memory-less node). If it is not, find
-    // the closest configured node.
-    if (!isnode_in_configured_nodes(nindex_to_node()->at(i))) {
+    // the closest configured node. Check also if node is bound, i.e. it's allowed
+    // to allocate memory from the node. If it's not allowed, map cpus in that node
+    // to the closest node from which memory allocation is allowed.
+    if (!isnode_in_configured_nodes(nindex_to_node()->at(i)) ||
+        !isnode_in_bound_nodes(nindex_to_node()->at(i))) {
       closest_distance = INT_MAX;
       // Check distance from all remaining nodes in the system. Ignore distance
-      // from itself and from another non-configured node.
+      // from itself, from another non-configured node, and from another non-bound
+      // node.
       for (size_t m = 0; m < node_num; m++) {
-        if (m != i && isnode_in_configured_nodes(nindex_to_node()->at(m))) {
+        if (m != i &&
+            isnode_in_configured_nodes(nindex_to_node()->at(m)) &&
+            isnode_in_bound_nodes(nindex_to_node()->at(m))) {
           distance = numa_distance(nindex_to_node()->at(i), nindex_to_node()->at(m));
           // If a closest node is found, update. There is always at least one
-          // configured node in the system so there is always at least one node
-          // close.
+          // configured and bound node in the system so there is always at least
+          // one node close.
           if (distance != 0 && distance < closest_distance) {
             closest_distance = distance;
             closest_node = nindex_to_node()->at(m);
@@ -3068,6 +3077,7 @@
 os::Linux::numa_set_bind_policy_func_t os::Linux::_numa_set_bind_policy;
 os::Linux::numa_bitmask_isbitset_func_t os::Linux::_numa_bitmask_isbitset;
 os::Linux::numa_distance_func_t os::Linux::_numa_distance;
+os::Linux::numa_get_membind_func_t os::Linux::_numa_get_membind;
 unsigned long* os::Linux::_numa_all_nodes;
 struct bitmask* os::Linux::_numa_all_nodes_ptr;
 struct bitmask* os::Linux::_numa_nodes_ptr;
@@ -5049,8 +5059,9 @@
     if (!Linux::libnuma_init()) {
       UseNUMA = false;
     } else {
-      if ((Linux::numa_max_node() < 1)) {
-        // There's only one node(they start from 0), disable NUMA.
+      if ((Linux::numa_max_node() < 1) || Linux::isbound_to_single_node()) {
+        // If there's only one node (they start from 0) or if the process
+        // is bound explicitly to a single node using membind, disable NUMA.
         UseNUMA = false;
       }
     }
--- a/src/hotspot/os/linux/os_linux.hpp	Sun Jul 22 20:00:39 2018 -0700
+++ b/src/hotspot/os/linux/os_linux.hpp	Thu Jul 19 16:56:05 2018 -0400
@@ -228,6 +228,7 @@
   typedef int (*numa_tonode_memory_func_t)(void *start, size_t size, int node);
   typedef void (*numa_interleave_memory_func_t)(void *start, size_t size, unsigned long *nodemask);
   typedef void (*numa_interleave_memory_v2_func_t)(void *start, size_t size, struct bitmask* mask);
+  typedef struct bitmask* (*numa_get_membind_func_t)(void);
 
   typedef void (*numa_set_bind_policy_func_t)(int policy);
   typedef int (*numa_bitmask_isbitset_func_t)(struct bitmask *bmp, unsigned int n);
@@ -244,6 +245,7 @@
   static numa_set_bind_policy_func_t _numa_set_bind_policy;
   static numa_bitmask_isbitset_func_t _numa_bitmask_isbitset;
   static numa_distance_func_t _numa_distance;
+  static numa_get_membind_func_t _numa_get_membind;
   static unsigned long* _numa_all_nodes;
   static struct bitmask* _numa_all_nodes_ptr;
   static struct bitmask* _numa_nodes_ptr;
@@ -259,6 +261,7 @@
   static void set_numa_set_bind_policy(numa_set_bind_policy_func_t func) { _numa_set_bind_policy = func; }
   static void set_numa_bitmask_isbitset(numa_bitmask_isbitset_func_t func) { _numa_bitmask_isbitset = func; }
   static void set_numa_distance(numa_distance_func_t func) { _numa_distance = func; }
+  static void set_numa_get_membind(numa_get_membind_func_t func) { _numa_get_membind = func; }
   static void set_numa_all_nodes(unsigned long* ptr) { _numa_all_nodes = ptr; }
   static void set_numa_all_nodes_ptr(struct bitmask **ptr) { _numa_all_nodes_ptr = (ptr == NULL ? NULL : *ptr); }
   static void set_numa_nodes_ptr(struct bitmask **ptr) { _numa_nodes_ptr = (ptr == NULL ? NULL : *ptr); }
@@ -299,7 +302,7 @@
     if (_numa_bitmask_isbitset != NULL && _numa_all_nodes_ptr != NULL) {
       return _numa_bitmask_isbitset(_numa_all_nodes_ptr, n);
     } else
-      return 0;
+      return false;
   }
   // Check if numa node exists in the system (including zero memory nodes).
   static bool isnode_in_existing_nodes(unsigned int n) {
@@ -318,7 +321,42 @@
       // substitute.
       return _numa_bitmask_isbitset(_numa_all_nodes_ptr, n);
     } else
-      return 0;
+      return false;
+  }
+  // Check if node is in bound node set.
+  static bool isnode_in_bound_nodes(int node) {
+    if (_numa_get_membind != NULL && _numa_bitmask_isbitset != NULL) {
+      return _numa_bitmask_isbitset(_numa_get_membind(), node);
+    } else {
+      return false;
+    }
+  }
+  // Check if bound to only one numa node.
+  // Returns true if bound to a single numa node, otherwise returns false.
+  static bool isbound_to_single_node() {
+    int nodes = 0;
+    struct bitmask* bmp = NULL;
+    unsigned int node = 0;
+    unsigned int highest_node_number = 0;
+
+    if (_numa_get_membind != NULL && _numa_max_node != NULL && _numa_bitmask_isbitset != NULL) {
+      bmp = _numa_get_membind();
+      highest_node_number = _numa_max_node();
+    } else {
+      return false;
+    }
+
+    for (node = 0; node <= highest_node_number; node++) {
+      if (_numa_bitmask_isbitset(bmp, node)) {
+        nodes++;
+      }
+    }
+
+    if (nodes == 1) {
+      return true;
+    } else {
+      return false;
+    }
   }
 };