Nim

Makefile

@@ -144,3 +144,35 @@ run-d: d
 analyze-d:
 	@echo "Max Pause: "
 	@cat d.log
+
+## Nim
+
+nim: main.nim
+	nim c -d:release -d:disableMS -d:useRealtimeGC main.nim
+
+clean::
+	rm -f main
+	rm -r nimcache
+
+run-nim: nim
+	./main > nim.log
+	cat nim.log
+
+analyze-nim:
+	@echo "Worst pause: "
+	@cat nim.log
+
+nim-ms: main.nim
+	nim c -d:release -d:useRealtimeGC main.nim
+
+clean::
+	rm -f main
+	rm -r nimcache
+
+run-nim-ms: nim
+	./main > nim-ms.log
+	cat nim-ms.log
+
+analyze-nim-ms:
+	@echo "Worst pause: "
+	@cat nim-ms.log

main.nim

@@ -0,0 +1,59 @@
+# Compile and run with 'nim c -r -d:useRealtimeGC -d:release main.nim'
+# See here for more info: http://forum.nim-lang.org/t/2646
+
+import strutils
+
+include "$lib/system/timers"
+
+const
+  windowSize = 200000
+  msgCount   = 1000000
+
+type
+  Msg = seq[byte]
+  Buffer = seq[Msg]
+
+var worst: Nanos
+
+proc mkMessage(n: int): Msg =
+  result = newSeq[byte](1024)
+  for i in 0 .. <result.len:
+    result[i] = byte(n)
+
+proc pushMsg0(b: var Buffer, highID: int) =
+  # warmup:
+  let m = mkMessage(highID)
+  shallowCopy(b[highID mod windowSize], m)
+
+proc pushMsg1(b: var Buffer, highID: int) =
+  # with benchmarking:
+  let start = getTicks()
+
+  let m = mkMessage(highID)
+  shallowCopy(b[highID mod windowSize], m)
+
+  let elapsed = getTicks() - start
+  if elapsed > worst:
+    worst = elapsed
+
+proc main() =
+  # Don't use GC_disable() and GC_step(). Instead use GC_setMaxPause().
+  when defined(disableMS):
+    GC_disableMarkAndSweep()
+  GC_setMaxPause(300)
+
+  var b = newSeq[Msg](windowSize)
+  # we need to warmup Nim's memory allocator so that not most
+  # of the time is spent in mmap()... Hopefully later versions of Nim
+  # will be smarter and allocate larger pieces from the OS:
+  for i in 0 .. <msgCount:
+    pushMsg0(b, i)
+
+  # now after warmup, we can measure things:
+  for i in 0 .. <msgCount:
+    pushMsg1(b, i)
+
+  echo(worst.float / 1_000_000.0, " ms")
+
+when isMainModule:
+  main()