Add support for Linux HugePages

Read the HugePages[0] information from `/proc/meminfo`.

[0]: https://www.kernel.org/doc/Documentation/vm/hugetlbpage.txt

2 files changed, 39 insertions, 3 deletions

diff --git a/lib/ohai/plugins/linux/memory.rb b/lib/ohai/plugins/linux/memory.rb
index b663ed1e..144ad9d7 100644
--- a/lib/ohai/plugins/linux/memory.rb
+++ b/lib/ohai/plugins/linux/memory.rb
@@ -22,6 +22,7 @@ Ohai.plugin(:Memory) do
   collect_data(:linux) do
     memory Mash.new
     memory[:swap] = Mash.new
+    memory[:hugepages] = Mash.new
 
     File.open("/proc/meminfo").each do |line|
       case line
@@ -81,6 +82,16 @@ Ohai.plugin(:Memory) do
         memory[:swap][:total] = "#{$1}#{$2}"
       when /^SwapFree:\s+(\d+) (.+)$/
         memory[:swap][:free] = "#{$1}#{$2}"
+      when /^HugePages_Total:\s+(\d+)$/
+        memory[:hugepages][:total] = "#{$1}"
+      when /^HugePages_Free:\s+(\d+)$/
+        memory[:hugepages][:free] = "#{$1}"
+      when /^HugePages_Rsvd:\s+(\d+)$/
+        memory[:hugepages][:reserved] = "#{$1}"
+      when /^HugePages_Surp:\s+(\d+)$/
+        memory[:hugepages][:surplus] = "#{$1}"
+      when /^Hugepagesize:\s+(\d+) (.+)$/
+        memory[:hugepage_size] = "#{$1}#{$2}"
       end
     end
   end
diff --git a/spec/unit/plugins/linux/memory_spec.rb b/spec/unit/plugins/linux/memory_spec.rb
index fd5bfc39..3a30ead3 100644
--- a/spec/unit/plugins/linux/memory_spec.rb
+++ b/spec/unit/plugins/linux/memory_spec.rb
@@ -50,9 +50,10 @@ describe Ohai::System, "Linux memory plugin" do
       and_yield("VmallocTotal: 34359738367 kB").
       and_yield("VmallocUsed:    276796 kB").
       and_yield("VmallocChunk: 34359461515 kB").
-      and_yield("HugePages_Total:     0").
-      and_yield("HugePages_Free:      0").
-      and_yield("HugePages_Rsvd:      0").
+      and_yield("HugePages_Total: 11542").
+      and_yield("HugePages_Free:  11235").
+      and_yield("HugePages_Rsvd:  11226").
+      and_yield("HugePages_Surp:      0").
       and_yield("Hugepagesize:     2048 kB")
     allow(File).to receive(:open).with("/proc/meminfo").and_return(@double_file)
   end
@@ -197,4 +198,28 @@ describe Ohai::System, "Linux memory plugin" do
     expect(@plugin[:memory][:swap][:free]).to eql("14127356kB")
   end
 
+  it "should get total hugepages" do
+    @plugin.run
+    expect(@plugin[:memory][:hugepages][:total]).to eql("11542")
+  end
+
+  it "should get free hugepages" do
+    @plugin.run
+    expect(@plugin[:memory][:hugepages][:free]).to eql("11235")
+  end
+
+  it "should get reserved hugepages" do
+    @plugin.run
+    expect(@plugin[:memory][:hugepages][:reserved]).to eql("11226")
+  end
+
+  it "should get surplus hugepages" do
+    @plugin.run
+    expect(@plugin[:memory][:hugepages][:surplus]).to eql("0")
+  end
+
+  it "should get hugepage size" do
+    @plugin.run
+    expect(@plugin[:memory][:hugepage_size]).to eql("2048kB")
+  end
 end