Add performances counter option

[SXSI/xpathcomp.git] / include / utils.ml

diff --git a/include/utils.ml b/include/utils.ml
index 5de5646..88a1dd2 100644 (file)
--- a/include/utils.ml
+++ b/include/utils.ml
@@ -69,6 +69,39 @@ let time_mem f x =
     Printf.eprintf "Final Mem: %s\n\n\n%!" s2;
     r
 ;;
+
+let pid = ref 0
+let start_perf () =
+
+  let ppid = Unix.getpid() in
+  let cmd = "/usr/bin/perf" in
+  if not (Sys.file_exists cmd) then (failwith "Binary '/usr/bin/perf' not found");
+  let args = [| cmd; "stat"; "--pid=" ^ (string_of_int ppid);
+               "-e"; "L1-dcache-load";
+               "-e"; "L1-dcache-load-misses";
+               "-e"; "L1-dcache-store";
+               "-e"; "L1-dcache-store-misses";
+               "-e"; "L1-icache-load";
+               "-e"; "L1-icache-load-misses";
+               "-e"; "branch-load";
+               "-e"; "branch-load-misses";
+               "-e"; "cpu-cycles";
+               "-e"; "stalled-cycles-frontend";
+               "-e"; "stalled-cycles-backend";
+               "-e"; "instructions";
+               "-e"; "cache-references";
+               "-e"; "cache-misses";
+               "-e"; "branch-instructions";
+               "-e"; "branch-misses";
+               "-e"; "bus-cycles";
+            |] in
+  let p =  Unix.fork() in
+  pid := p;
+  if !pid == 0 then Unix.execv cmd args
+
+let stop_perf () =
+  Unix.kill !pid Sys.sigint
+
 let time f ?(count=1) ?(msg="") x =
   let rec loop i =
     Gc.compact();