rocksdb/util/env.cc
Dhruba Borthakur ad96563b79 Ability to configure bufferedio-reads, filesystem-readaheads and mmap-read-write per database.
Summary:
This patch allows an application to specify whether to use bufferedio,
reads-via-mmaps and writes-via-mmaps per database. Earlier, there
was a global static variable that was used to configure this functionality.

The default setting remains the same (and is backward compatible):
 1. use bufferedio
 2. do not use mmaps for reads
 3. use mmap for writes
 4. use readaheads for reads needed for compaction

I also added a parameter to db_bench to be able to explicitly specify
whether to do readaheads for compactions or not.

Test Plan: make check

Reviewers: sheki, heyongqiang, MarkCallaghan

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9429
2013-03-20 23:14:03 -07:00

104 lines
2.3 KiB
C++

// 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 "leveldb/env.h"
#include "util/storage_options.h"
namespace leveldb {
Env::~Env() {
}
SequentialFile::~SequentialFile() {
}
RandomAccessFile::~RandomAccessFile() {
}
WritableFile::~WritableFile() {
}
Logger::~Logger() {
}
FileLock::~FileLock() {
}
void Log(Logger* info_log, const char* format, ...) {
if (info_log) {
va_list ap;
va_start(ap, format);
info_log->Logv(format, ap);
va_end(ap);
}
}
void Log(const shared_ptr<Logger>& info_log, const char* format, ...) {
if (info_log) {
va_list ap;
va_start(ap, format);
info_log->Logv(format, ap);
va_end(ap);
}
}
static Status DoWriteStringToFile(Env* env, const Slice& data,
const std::string& fname,
bool should_sync) {
unique_ptr<WritableFile> file;
StorageOptions soptions;
Status s = env->NewWritableFile(fname, &file, soptions);
if (!s.ok()) {
return s;
}
s = file->Append(data);
if (s.ok() && should_sync) {
s = file->Sync();
}
if (!s.ok()) {
env->DeleteFile(fname);
}
return s;
}
Status WriteStringToFile(Env* env, const Slice& data,
const std::string& fname) {
return DoWriteStringToFile(env, data, fname, false);
}
Status WriteStringToFileSync(Env* env, const Slice& data,
const std::string& fname) {
return DoWriteStringToFile(env, data, fname, true);
}
Status ReadFileToString(Env* env, const std::string& fname, std::string* data) {
StorageOptions soptions;
data->clear();
unique_ptr<SequentialFile> file;
Status s = env->NewSequentialFile(fname, &file, soptions);
if (!s.ok()) {
return s;
}
static const int kBufferSize = 8192;
char* space = new char[kBufferSize];
while (true) {
Slice fragment;
s = file->Read(kBufferSize, &fragment, space);
if (!s.ok()) {
break;
}
data->append(fragment.data(), fragment.size());
if (fragment.empty()) {
break;
}
}
delete[] space;
return s;
}
EnvWrapper::~EnvWrapper() {
}
} // namespace leveldb