serializer: reserve an interval size of instuctions for warm up (#361)

* serializer: reserve an interval size of instuctions for warm up before ROI
* Add warmup interval option, support manually specify the interval of warmup, the default value is equal to the checkpoint interval


---------

Signed-off-by: jiaxiaoyu <[email protected]>

include/checkpoint/serializer.h

@@ -47,6 +47,7 @@ class Serializer
   private:
 
     uint64_t intervalSize{10 * 1000 * 1000};
+    uint64_t warmupIntervalSize{10 * 1000 * 1000};
 
     int cptID;
     std::string weightIndicator;

include/profiling/profiling_control.h

@@ -20,6 +20,7 @@ extern int profiling_state;
 extern int checkpoint_state;
 extern bool checkpoint_restoring;
 extern uint64_t checkpoint_interval;
+extern uint64_t warmup_interval;
 
 extern bool recvd_manual_oneshot_cpt;
 extern bool recvd_manual_uniform_cpt;

src/checkpoint/serializer.cpp

@@ -242,6 +242,7 @@ void Serializer::init() {
   if  (checkpoint_state == SimpointCheckpointing) {
     assert(checkpoint_interval);
     intervalSize = checkpoint_interval;
+    warmupIntervalSize = warmup_interval;
     Log("Taking simpoint checkpionts with profiling interval %lu", checkpoint_interval);
 
     auto simpoints_file = fstream(pathManager.getSimpointPath() + "simpoints0");
@@ -275,9 +276,9 @@ bool Serializer::instrsCouldTakeCpt(uint64_t num_insts) {
       if (simpoint2Weights.empty()) {
         break;
       } else {
-        uint64_t next_point = simpoint2Weights.begin()->first * intervalSize + 100000;
+        uint64_t next_point = (simpoint2Weights.begin()->first * intervalSize) <= warmupIntervalSize ? 0 : (simpoint2Weights.begin()->first * intervalSize) - warmupIntervalSize;
         if (num_insts >= next_point) {
-          Log("Should take cpt now: %lu", num_insts);
+          Log("Should take cpt now: %lu next point %lu", num_insts, next_point);
           return true;
         } else if (num_insts % intervalSize == 0) {
           Log("First cpt @ %lu, now: %lu", next_point, num_insts);

src/monitor/monitor.c

@@ -105,6 +105,7 @@ static inline int parse_args(int argc, char *argv[]) {
     {"manual-oneshot-cpt" , no_argument      , NULL, 11},
     {"manual-uniform-cpt" , no_argument      , NULL, 9},
     {"cpt-interval"       , required_argument, NULL, 5},
+    {"warmup-interval"    , required_argument, NULL, 14},
     {"cpt-mmode"          , no_argument      , NULL, 7},
     {"map-cpt"            , required_argument, NULL, 10},
     {"checkpoint-format"  , required_argument, NULL, 12},
@@ -240,6 +241,7 @@ static inline int parse_args(int argc, char *argv[]) {
         log_file = optarg;
         small_log = true;
         break;
+      case 14: sscanf(optarg, "%lu", &warmup_interval); break;
 
       default:
         printf("Usage: %s [OPTION...] IMAGE [args]\n\n", argv[0]);
@@ -261,6 +263,7 @@ static inline int parse_args(int argc, char *argv[]) {
         printf("\t-S,--simpoint-dir=SIMPOINT_DIR   simpoints dir\n");
         printf("\t-u,--uniform-cpt        uniformly take cpt with fixed interval\n");
         printf("\t--cpt-interval=INTERVAL cpt interval: the profiling period for simpoint; the checkpoint interval for uniform cpt\n");
+        printf("\t--warmup-interval=INTERVAL warmup interval: the warmup interval for SimPoint cpt\n");
         printf("\t--cpt-mmode             force to take cpt in mmode, which might not work.\n");
         printf("\t--manual-oneshot-cpt    Manually take one-shot cpt by send signal.\n");
         printf("\t--manual-uniform-cpt    Manually take uniform cpt by send signal.\n");
@@ -290,6 +293,10 @@ void init_monitor(int argc, char *argv[]) {
   parse_args(argc, argv);
 #endif
 
+  if (warmup_interval == 0) {
+    warmup_interval = checkpoint_interval;
+  }
+
   if (map_image_as_output_cpt) {
     assert(!mapped_cpt_file);
     mapped_cpt_file = img_file;

src/profiling/profiling_control.c

@@ -5,6 +5,7 @@ int checkpoint_state = NoCheckpoint;
 bool checkpoint_taking = false;
 bool checkpoint_restoring = false;
 uint64_t checkpoint_interval = 0;
+uint64_t warmup_interval = 0;
 
 bool recvd_manual_oneshot_cpt = false;
 bool recvd_manual_uniform_cpt = false;