src/hotspot/os/linux/os_linux.cpp

rev 59103 : [mq]: take2

@@ -5173,11 +5173,12 @@
   // numa_all_nodes_ptr holds bitmask of all nodes.
   // numa_get_interleave_mask(v2) and numa_get_membind(v2) APIs returns correct
   // bitmask when externally configured to run on all or fewer nodes.
 
   if (!Linux::libnuma_init()) {
-    UseNUMA = false;
+    FLAG_SET_ERGO(UseNUMA, false);
+    FLAG_SET_ERGO(UseNUMAInterleaving, false); // Also depends on libnuma.
   } else {
     if ((Linux::numa_max_node() < 1) || Linux::is_bound_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 unless
       // user explicilty forces NUMA optimizations on single-node/UMA systems

@@ -5206,10 +5207,15 @@
         }
       }
     }
   }
 
+  // When NUMA requested, not-NUMA-aware allocations default to interleaving.
+  if (UseNUMA && !UseNUMAInterleaving) {
+    FLAG_SET_ERGO_IF_DEFAULT(UseNUMAInterleaving, true);
+  }
+
   if (UseParallelGC && UseNUMA && UseLargePages && !can_commit_large_page_memory()) {
     // With SHM and HugeTLBFS large pages we cannot uncommit a page, so there's no way
     // we can make the adaptive lgrp chunk resizing work. If the user specified both
     // UseNUMA and UseLargePages (or UseSHM/UseHugeTLBFS) on the command line - warn
     // and disable adaptive resizing.

@@ -5270,11 +5276,11 @@
   Linux::libpthread_init();
   Linux::sched_getcpu_init();
   log_info(os)("HotSpot is running with %s, %s",
                Linux::glibc_version(), Linux::libpthread_version());
 
-  if (UseNUMA) {
+  if (UseNUMA || UseNUMAInterleaving) {
     Linux::numa_init();
   }
 
   if (MaxFDLimit) {
     // set the number of file descriptors to max. print out error