Added simple decode benchmark.

baibaichen · May 20, 2014 · 722c751 · 722c751
1 parent 0959d2a
commit 722c751
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Showing 3 changed files with 78 additions and 1 deletion.
diff --git a/example/CMakeLists.txt b/example/CMakeLists.txt
@@ -19,3 +19,6 @@ add_library(Example STATIC
 
 add_executable(compute_stats compute_stats.cc)
 target_link_libraries(compute_stats Parquet Example ThriftParquet thriftstatic)
+
+add_executable(decode_benchmark decode_benchmark.cc)
+target_link_libraries(decode_benchmark Parquet Example ThriftParquet thriftstatic rt)
diff --git a/example/decode_benchmark.cc b/example/decode_benchmark.cc
@@ -0,0 +1,74 @@
+#include <parquet/parquet.h>
+#include <iostream>
+#include <stdio.h>
+
+#include "example_util.h"
+#include "encodings.h"
+
+using namespace parquet;
+using namespace parquet_cpp;
+using namespace std;
+
+class StopWatch {
+ public:
+  StopWatch() {
+  }
+
+  void Start() {
+    clock_gettime(CLOCK_MONOTONIC, &start_);
+  }
+
+  // Returns time in nanoseconds.
+  uint64_t Stop() {
+    timespec end;
+    clock_gettime(CLOCK_MONOTONIC, &end);
+    return (end.tv_sec - start_.tv_sec) * 1000L * 1000L * 1000L +
+           (end.tv_nsec - start_.tv_nsec);
+  }
+
+ private:
+  timespec start_;
+};
+
+uint64_t TestPlainIntEncoding(const uint8_t* data, int num_values, int batch_size) {
+  uint64_t result = 0;
+  PlainDecoder decoder(NULL);
+  decoder.SetData(num_values, data, num_values * sizeof(int32_t));
+  int32_t values[batch_size];
+  for (int i = 0; i < num_values;) {
+    int n = decoder.GetInt32(values, batch_size);
+    for (int j = 0; j < n; ++j) {
+      result += values[j];
+    }
+    i += n;
+  }
+  return result;
+}
+
+#define TEST(NAME, FN, DATA, BATCH_SIZE)\
+  sw.Start();\
+  for (int i = 0; i < NUM_ITERS; ++i) {\
+    FN(reinterpret_cast<uint8_t*>(&DATA[0]), NUM_VALUES, BATCH_SIZE);\
+  }\
+  elapsed = sw.Stop();\
+  printf("%s rate (batch size = %2d): %0.2f per second.\n",\
+      NAME, BATCH_SIZE, mult / elapsed);
+
+int main(int argc, char** argv) {
+  StopWatch sw;
+  uint64_t elapsed = 0;
+
+  const int NUM_VALUES = 1024 * 1024;
+  const int NUM_ITERS = 10;
+  const double mult = NUM_VALUES * 1000. * 1000. * 1000. * NUM_ITERS;
+
+  vector<int32_t> plain_int_data;
+  plain_int_data.resize(NUM_VALUES);
+
+  TEST("Plain decoder", TestPlainIntEncoding, plain_int_data, 1);
+  TEST("Plain decoder", TestPlainIntEncoding, plain_int_data, 16);
+  TEST("Plain decoder", TestPlainIntEncoding, plain_int_data, 32);
+  TEST("Plain decoder", TestPlainIntEncoding, plain_int_data, 64);
+
+  return 0;
+}
diff --git a/src/encodings.h b/src/encodings.h
@@ -93,7 +93,7 @@ class PlainDecoder : public Decoder {
   int GetValues(void* buffer, int max_values, int byte_size) {
     max_values = std::min(max_values, num_values_);
     int size = max_values * byte_size;
-    if (size < len_)  ParquetException::EofException();
+    if (len_ < size)  ParquetException::EofException();
     memcpy(buffer, data_, size);
     data_ += size;
     len_ -= size;