memory limit WIP

Author: pcanal

io/io/test/CMakeLists.txt

@@ -72,27 +72,24 @@ if(NOT _32BIT)
   set(_memcheck_script "${CMAKE_CURRENT_BINARY_DIR}/check_mem_for_large_coll.sh")
   file(WRITE ${_memcheck_script}
     "#!/bin/sh\n"
-    "# Exit 77 (CTest SKIP via SKIP_RETURN_CODE) if free RAM+swap < 32 GB.\n"
+    "# Exit 77 (CTest SKIP via SKIP_RETURN_CODE) if total RAM+swap < 32 GB.\n"
+    "# We use TOTAL (not free) because the OS reclaims cached pages on demand.\n"
     "THRESHOLD_KB=33554432\n"
     "if [ -r /proc/meminfo ]; then\n"
-    "  # Linux\n"
-    "  RAM_KB=\$(awk '/^MemAvailable:/{print \$2}' /proc/meminfo)\n"
-    "  SWAP_KB=\$(awk '/^SwapFree:/{print \$2}' /proc/meminfo)\n"
+    "  # Linux: use MemTotal + SwapTotal (kernel will reclaim caches as needed)\n"
+    "  RAM_KB=\$(awk '/^MemTotal:/{print \$2}' /proc/meminfo)\n"
+    "  SWAP_KB=\$(awk '/^SwapTotal:/{print \$2}' /proc/meminfo)\n"
     "  RAM_KB=\${RAM_KB:-0}\n"
     "  SWAP_KB=\${SWAP_KB:-0}\n"
     "  TOTAL_KB=\$(( RAM_KB + SWAP_KB ))\n"
     "elif [ \"\$(uname)\" = \"Darwin\" ]; then\n"
-    "  # macOS: free+speculative pages via vm_stat, free swap via sysctl vm.swapusage\n"
-    "  PAGE_SIZE=\$(pagesize)\n"
-    "  FREE_PAGES=\$(vm_stat | awk '/^Pages free:/{gsub(\"\\\\.\",\"\",\$3); print \$3}')\n"
-    "  SPEC_PAGES=\$(vm_stat | awk '/^Pages speculative:/{gsub(\"\\\\.\",\"\",\$3); print \$3}')\n"
-    "  FREE_PAGES=\${FREE_PAGES:-0}\n"
-    "  SPEC_PAGES=\${SPEC_PAGES:-0}\n"
-    "  RAM_KB=\$(( (FREE_PAGES + SPEC_PAGES) * PAGE_SIZE / 1024 ))\n"
-    "  # sysctl output: 'total = NNN.NNM  used = NNN.NNM  free = NNN.NNM  (encrypted)'\n"
-    "  SWAP_FREE_MB=\$(sysctl -n vm.swapusage 2>/dev/null | sed 's/.*free = \\([0-9.]*\\)M.*/\\1/')\n"
-    "  if [ -n \"\$SWAP_FREE_MB\" ]; then\n"
-    "    SWAP_KB=\$(awk \"BEGIN{printf \\\"%d\\\", \$SWAP_FREE_MB * 1024}\")\n"
+    "  # macOS: total physical RAM via sysctl hw.memsize (bytes -> kB)\n"
+    "  RAM_BYTES=\$(sysctl -n hw.memsize 2>/dev/null)\n"
+    "  RAM_KB=\$(( \${RAM_BYTES:-0} / 1024 ))\n"
+    "  # sysctl output: 'total = NNN.NNM  used = ...  free = ...'\n"
+    "  SWAP_TOTAL_MB=\$(sysctl -n vm.swapusage 2>/dev/null | sed 's/total = \\([0-9.]*\\)M.*/\\1/')\n"
+    "  if [ -n \"\$SWAP_TOTAL_MB\" ]; then\n"
+    "    SWAP_KB=\$(awk \"BEGIN{printf \\\"%d\\\", \$SWAP_TOTAL_MB * 1024}\")\n"
     "  else\n"
     "    SWAP_KB=0\n"
     "  fi\n"
@@ -101,7 +98,7 @@ if(NOT _32BIT)
     "  echo \"testLargeCollections memory check: unsupported OS, assuming enough memory\"\n"
     "  exit 0\n"
     "fi\n"
-    "echo \"testLargeCollections memory check: available \${TOTAL_KB} kB (RAM \${RAM_KB} + swap \${SWAP_KB}), need \${THRESHOLD_KB} kB\"\n"
+    "echo \"testLargeCollections memory check: total \${TOTAL_KB} kB (RAM \${RAM_KB} + swap \${SWAP_KB}), need \${THRESHOLD_KB} kB\"\n"
     "if [ \"\$TOTAL_KB\" -lt \"\$THRESHOLD_KB\" ]; then\n"
     "  echo \"Insufficient memory -- skipping testLargeCollections\"\n"
     "  exit 77\n"