对原版leveldb进行插桩

db/db_impl.cc

@@ -1235,12 +1235,18 @@ Status DBImpl::Write(const WriteOptions& options, WriteBatch* updates) {
   w.sync = options.sync;
   w.done = false;
 
+  uint64_t start_ = env_->NowMicros();
   MutexLock l(&mutex_);
+  count ++;
   writers_.push_back(&w);
   while (!w.done && &w != writers_.front()) {
     w.cv.Wait();
   }
   if (w.done) {
+    Waiting_elapsed += env_->NowMicros() - start_;
+    waited_count ++;
+    Total_elapsed += env_->NowMicros() - start_;
+    // dumpStatistics();
     return w.status;
   }
 
@@ -1259,6 +1265,7 @@ Status DBImpl::Write(const WriteOptions& options, WriteBatch* updates) {
     // into mem_.
     {
       mutex_.Unlock();
+      uint64_t start_write = env_->NowMicros();
       status = log_->AddRecord(WriteBatchInternal::Contents(write_batch));
       bool sync_error = false;
       if (status.ok() && options.sync) {
@@ -1270,6 +1277,8 @@ Status DBImpl::Write(const WriteOptions& options, WriteBatch* updates) {
       if (status.ok()) {
         status = WriteBatchInternal::InsertInto(write_batch, mem_);
       }
+      BatchSize += write_batch->ApproximateSize();
+      write_elapsed += env_->NowMicros() - start_write;
       mutex_.Lock();
       if (sync_error) {
         // The state of the log file is indeterminate: the log record we
@@ -1298,7 +1307,10 @@ Status DBImpl::Write(const WriteOptions& options, WriteBatch* updates) {
   if (!writers_.empty()) {
     writers_.front()->cv.Signal();
   }
-
+  Total_elapsed += env_->NowMicros() - start_;
+  NoWaiting_elapsed += env_->NowMicros() - start_;
+  Nowaited_count ++;
+  dumpStatistics();
   return status;
 }
 

db/db_impl.h

@@ -6,7 +6,10 @@
 #define STORAGE_LEVELDB_DB_DB_IMPL_H_
 
 #include <atomic>
+#include <cstdint>
+#include <cstdio>
 #include <deque>
+#include <ostream>
 #include <set>
 #include <string>
 
@@ -210,6 +213,33 @@ class DBImpl : public DB {
   Status bg_error_ GUARDED_BY(mutex_);
 
   CompactionStats stats_[config::kNumLevels] GUARDED_BY(mutex_);
+
+  int count = 0;
+  int waited_count = 0;
+  int Nowaited_count = 0;
+  uint64_t Total_elapsed = 0;
+  uint64_t Waiting_elapsed = 0;
+  uint64_t NoWaiting_elapsed = 0;
+  uint64_t write_elapsed = 0;
+  uint64_t BatchSize = 0;
+  const double MB = 1024 * 1024;
+  const double KB = 1024;
+  inline void dumpStatistics() {
+    if(count && count % 500000 == 0) {
+      printf("==================================\n");
+      printf("Count: Total:%d    Waited:%d    Nowaited:%d\n",count,waited_count,Nowaited_count);
+      printf("%ld %ld %ld\n",Total_elapsed,Waiting_elapsed,NoWaiting_elapsed);
+      printf("Average Total elapsed:   %lf ms\n",Total_elapsed * 1.0 / count);
+      printf("Average Waiting elapsed: %lf ms\n",Waiting_elapsed * 1.0 / count);
+      printf("For waiting request:     %lf ms\n",Waiting_elapsed * 1.0 / waited_count);
+      printf("For Nowait request:      %lf ms\n",NoWaiting_elapsed * 1.0 / Nowaited_count);
+      printf("Write elapsed:           %lf ms\n",write_elapsed * 1.0 / Nowaited_count);
+      printf("Average BatchSize:       %lfKB\n",BatchSize / KB / count);
+      printf("Average BatchSize per write:%lfKB\n",BatchSize / KB / Nowaited_count);
+      printf("==================================\n");
+      std::fflush(stdout);
+    }
+  }
 };
 
 // Sanitize db options.  The caller should delete result.info_log if