Initial checkin.

git-svn-id: https://leveldb.googlecode.com/svn/trunk@2 62dab493-f737-651d-591e-8d6aee1b9529

1 files changed, 376 insertions, 0 deletions

diff --git a/db/db_bench.cc b/db/db_bench.cc
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+++ b/db/db_bench.cc
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+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include <sys/types.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include "db/db_impl.h"
+#include "db/version_set.h"
+#include "include/cache.h"
+#include "include/db.h"
+#include "include/env.h"
+#include "include/write_batch.h"
+#include "util/histogram.h"
+#include "util/random.h"
+#include "util/testutil.h"
+
+// Comma-separated list of operations to run in the specified order
+//   Actual benchmarks:
+//      writeseq    -- write N values in sequential key order
+//      writerandom -- write N values in random key order
+//      writebig    -- write N/1000 100K valuesin random order
+//      readseq     -- read N values sequentially
+//      readrandom  -- read N values in random order
+//   Meta operations:
+//      compact     -- Compact the entire DB
+//      heapprofile -- Dump a heap profile (if supported by this port)
+//      sync        -- switch to synchronous writes (not the default)
+//      nosync      -- switch to asynchronous writes (the default)
+//      tenth       -- divide N by 10 (i.e., following benchmarks are smaller)
+//      normal      -- reset N back to its normal value (1000000)
+static const char* FLAGS_benchmarks =
+    "writeseq,"
+    "writeseq,"
+    "writerandom,"
+    "sync,tenth,tenth,writerandom,nosync,normal,"
+    "readseq,"
+    "readrandom,"
+    "compact,"
+    "readseq,"
+    "readrandom,"
+    "writebig";
+
+// Number of key/values to place in database
+static int FLAGS_num = 1000000;
+
+// Size of each value
+static int FLAGS_value_size = 100;
+
+// Arrange to generate values that shrink to this fraction of
+// their original size after compression
+static double FLAGS_compression_ratio = 0.25;
+
+// Print histogram of operation timings
+static bool FLAGS_histogram = false;
+
+// Number of bytes to buffer in memtable before compacting
+static int FLAGS_write_buffer_size = 1 << 20;
+
+namespace leveldb {
+
+// Helper for quickly generating random data.
+namespace {
+class RandomGenerator {
+ private:
+  std::string data_;
+  int pos_;
+
+ public:
+  RandomGenerator() {
+    // We use a limited amount of data over and over again and ensure
+    // that it is larger than the compression window (32KB), and also
+    // large enough to serve all typical value sizes we want to write.
+    Random rnd(301);
+    std::string piece;
+    while (data_.size() < 1048576) {
+      // Add a short fragment that is as compressible as specified
+      // by FLAGS_compression_ratio.
+      test::CompressibleString(&rnd, FLAGS_compression_ratio, 100, &piece);
+      data_.append(piece);
+    }
+    pos_ = 0;
+  }
+
+  Slice Generate(int len) {
+    if (pos_ + len > data_.size()) {
+      pos_ = 0;
+      assert(len < data_.size());
+    }
+    pos_ += len;
+    return Slice(data_.data() + pos_ - len, len);
+  }
+};
+}
+
+class Benchmark {
+ private:
+  Cache* cache_;
+  DB* db_;
+  int num_;
+  bool sync_;
+  int heap_counter_;
+  double start_;
+  double last_op_finish_;
+  int64_t bytes_;
+  std::string message_;
+  Histogram hist_;
+  RandomGenerator gen_;
+  Random rand_;
+
+  // State kept for progress messages
+  int done_;
+  int next_report_;     // When to report next
+
+  void Start() {
+    start_ = Env::Default()->NowMicros() * 1e-6;
+    bytes_ = 0;
+    message_.clear();
+    last_op_finish_ = start_;
+    hist_.Clear();
+    done_ = 0;
+    next_report_ = 100;
+  }
+
+  void FinishedSingleOp() {
+    if (FLAGS_histogram) {
+      double now = Env::Default()->NowMicros() * 1e-6;
+      double micros = (now - last_op_finish_) * 1e6;
+      hist_.Add(micros);
+      if (micros > 20000) {
+        fprintf(stderr, "long op: %.1f micros%30s\r", micros, "");
+        fflush(stderr);
+      }
+      last_op_finish_ = now;
+    }
+
+    done_++;
+    if (done_ >= next_report_) {
+      if (next_report_ < 1000) {
+        next_report_ += 100;
+      } else if (next_report_ < 10000) {
+        next_report_ += 1000;
+      } else if (next_report_ < 100000) {
+        next_report_ += 10000;
+      } else {
+        next_report_ += 100000;
+      }
+      fprintf(stderr, "... finished %d ops%30s\r", done_, "");
+      fflush(stderr);
+    }
+  }
+
+  void Stop(const Slice& name) {
+    double finish = Env::Default()->NowMicros() * 1e-6;
+
+    // Pretend at least one op was done in case we are running a benchmark
+    // that does nto call FinishedSingleOp().
+    if (done_ < 1) done_ = 1;
+
+    if (bytes_ > 0) {
+      char rate[100];
+      snprintf(rate, sizeof(rate), "%5.1f MB/s",
+               (bytes_ / 1048576.0) / (finish - start_));
+      if (!message_.empty()) {
+        message_.push_back(' ');
+      }
+      message_.append(rate);
+    }
+
+    fprintf(stdout, "%-12s : %10.3f micros/op;%s%s\n",
+            name.ToString().c_str(),
+            (finish - start_) * 1e6 / done_,
+            (message_.empty() ? "" : " "),
+            message_.c_str());
+    if (FLAGS_histogram) {
+      fprintf(stdout, "Microseconds per op:\n%s\n", hist_.ToString().c_str());
+    }
+    fflush(stdout);
+  }
+
+ public:
+  enum Order { SEQUENTIAL, RANDOM };
+
+  Benchmark() : cache_(NewLRUCache(200<<20)),
+                db_(NULL),
+                num_(FLAGS_num),
+                sync_(false),
+                heap_counter_(0),
+                bytes_(0),
+                rand_(301) {
+    std::vector<std::string> files;
+    Env::Default()->GetChildren("/tmp/dbbench", &files);
+    for (int i = 0; i < files.size(); i++) {
+      if (Slice(files[i]).starts_with("heap-")) {
+        Env::Default()->DeleteFile("/tmp/dbbench/" + files[i]);
+      }
+    }
+    DestroyDB("/tmp/dbbench", Options());
+  }
+
+  ~Benchmark() {
+    delete db_;
+    delete cache_;
+  }
+
+  void Run() {
+    Options options;
+    options.create_if_missing = true;
+    options.max_open_files = 10000;
+    options.block_cache = cache_;
+    options.write_buffer_size = FLAGS_write_buffer_size;
+
+    Start();
+    Status s = DB::Open(options, "/tmp/dbbench", &db_);
+    Stop("open");
+    if (!s.ok()) {
+      fprintf(stderr, "open error: %s\n", s.ToString().c_str());
+      exit(1);
+    }
+
+    const char* benchmarks = FLAGS_benchmarks;
+    while (benchmarks != NULL) {
+      const char* sep = strchr(benchmarks, ',');
+      Slice name;
+      if (sep == NULL) {
+        name = benchmarks;
+        benchmarks = NULL;
+      } else {
+        name = Slice(benchmarks, sep - benchmarks);
+        benchmarks = sep + 1;
+      }
+
+      Start();
+      if (name == Slice("writeseq")) {
+        Write(SEQUENTIAL, num_, FLAGS_value_size);
+      } else if (name == Slice("writerandom")) {
+        Write(RANDOM, num_, FLAGS_value_size);
+      } else if (name == Slice("writebig")) {
+        Write(RANDOM, num_ / 1000, 100 * 1000);
+      } else if (name == Slice("readseq")) {
+        Read(SEQUENTIAL);
+      } else if (name == Slice("readrandom")) {
+        Read(RANDOM);
+      } else if (name == Slice("compact")) {
+        Compact();
+      } else if (name == Slice("heapprofile")) {
+        HeapProfile();
+      } else if (name == Slice("sync")) {
+        sync_ = true;
+      } else if (name == Slice("nosync")) {
+        sync_ = false;
+      } else if (name == Slice("tenth")) {
+        num_ = num_ / 10;
+      } else if (name == Slice("normal")) {
+        num_ = FLAGS_num;
+      } else {
+        fprintf(stderr, "unknown benchmark '%s'\n", name.ToString().c_str());
+      }
+      Stop(name);
+    }
+  }
+
+  void Write(Order order, int num_entries, int value_size) {
+    WriteBatch batch;
+    Status s;
+    std::string val;
+    WriteOptions options;
+    options.sync = sync_;
+    for (int i = 0; i < num_entries; i++) {
+      const int k = (order == SEQUENTIAL) ? i : (rand_.Next() % FLAGS_num);
+      char key[100];
+      snprintf(key, sizeof(key), "%012d", k);
+      batch.Clear();
+      batch.Put(key, gen_.Generate(value_size));
+      s = db_->Write(options, &batch);
+      bytes_ += value_size + strlen(key);
+      if (!s.ok()) {
+        fprintf(stderr, "put error: %s\n", s.ToString().c_str());
+        exit(1);
+      }
+      FinishedSingleOp();
+    }
+  }
+
+  void Read(Order order) {
+    ReadOptions options;
+    if (order == SEQUENTIAL) {
+      Iterator* iter = db_->NewIterator(options);
+      int i = 0;
+      for (iter->SeekToFirst(); i < num_ && iter->Valid(); iter->Next()) {
+        bytes_ += iter->key().size() + iter->value().size();
+        FinishedSingleOp();
+        ++i;
+      }
+      delete iter;
+    } else {
+      std::string value;
+      for (int i = 0; i < num_; i++) {
+        char key[100];
+        const int k = (order == SEQUENTIAL) ? i : (rand_.Next() % FLAGS_num);
+        snprintf(key, sizeof(key), "%012d", k);
+        db_->Get(options, key, &value);
+        FinishedSingleOp();
+      }
+    }
+  }
+
+  void Compact() {
+    DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
+    dbi->TEST_CompactMemTable();
+    int max_level_with_files = 1;
+    for (int level = 1; level < config::kNumLevels; level++) {
+      uint64_t v;
+      char name[100];
+      snprintf(name, sizeof(name), "leveldb.num-files-at-level%d", level);
+      if (db_->GetProperty(name, &v) && v > 0) {
+        max_level_with_files = level;
+      }
+    }
+    for (int level = 0; level < max_level_with_files; level++) {
+      dbi->TEST_CompactRange(level, "", "~");
+    }
+  }
+
+  static void WriteToFile(void* arg, const char* buf, int n) {
+    reinterpret_cast<WritableFile*>(arg)->Append(Slice(buf, n));
+  }
+
+  void HeapProfile() {
+    char fname[100];
+    snprintf(fname, sizeof(fname), "/tmp/dbbench/heap-%04d", ++heap_counter_);
+    WritableFile* file;
+    Status s = Env::Default()->NewWritableFile(fname, &file);
+    if (!s.ok()) {
+      message_ = s.ToString();
+      return;
+    }
+    bool ok = port::GetHeapProfile(WriteToFile, file);
+    delete file;
+    if (!ok) {
+      message_ = "not supported";
+      Env::Default()->DeleteFile(fname);
+    }
+  }
+};
+
+}
+
+int main(int argc, char** argv) {
+  for (int i = 1; i < argc; i++) {
+    double d;
+    int n;
+    char junk;
+    if (leveldb::Slice(argv[i]).starts_with("--benchmarks=")) {
+      FLAGS_benchmarks = argv[i] + strlen("--benchmarks=");
+    } else if (sscanf(argv[i], "--compression_ratio=%lf%c", &d, &junk) == 1) {
+      FLAGS_compression_ratio = d;
+    } else if (sscanf(argv[i], "--histogram=%d%c", &n, &junk) == 1 &&
+               (n == 0 || n == 1)) {
+      FLAGS_histogram = n;
+    } else if (sscanf(argv[i], "--num=%d%c", &n, &junk) == 1) {
+      FLAGS_num = n;
+    } else if (sscanf(argv[i], "--value_size=%d%c", &n, &junk) == 1) {
+      FLAGS_value_size = n;
+    } else if (sscanf(argv[i], "--write_buffer_size=%d%c", &n, &junk) == 1) {
+      FLAGS_write_buffer_size = n;
+    }  else {
+      fprintf(stderr, "Invalid flag '%s'\n", argv[i]);
+      exit(1);
+    }
+  }
+
+  leveldb::Benchmark benchmark;
+  benchmark.Run();
+  return 0;
+}