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Split posix storage backend into Env and library

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Summary: This patch splits the posix storage backend into Env and
the actual *File implementations. The motivation is to allow other Envs
to use posix as a library. This enables a storage backend different from
posix to split its secondary storage between a normal file system
partition managed by posix, and it own media.

Test Plan: No new functionality is added to posix Env or the library,
thus the current tests should suffice.
This commit is contained in:
Javier González 2015-10-14 10:14:53 +02:00
parent d0d13ebf67
commit 6e6dd5f6f9
7 changed files with 839 additions and 738 deletions
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2
build_tools/build_detect_platform
View File

@ -45,7 +45,7 @@ fi
# we depend on C++11 # we depend on C++11
PLATFORM_CXXFLAGS="-std=c++11" PLATFORM_CXXFLAGS="-std=c++11"
# we currently depend on POSIX platform # we currently depend on POSIX platform
COMMON_FLAGS="-DROCKSDB_PLATFORM_POSIX" COMMON_FLAGS="-DROCKSDB_PLATFORM_POSIX -DROCKSDB_LIB_IO_POSIX"
# Default to fbcode gcc on internal fb machines # Default to fbcode gcc on internal fb machines
if [ -z "$ROCKSDB_NO_FBCODE" -a -d /mnt/gvfs/third-party ]; then if [ -z "$ROCKSDB_NO_FBCODE" -a -d /mnt/gvfs/third-party ]; then

2
build_tools/fbcode_config.sh
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@ -116,7 +116,7 @@ else
fi fi
CFLAGS+=" $DEPS_INCLUDE" CFLAGS+=" $DEPS_INCLUDE"
CFLAGS+=" -DROCKSDB_PLATFORM_POSIX -DROCKSDB_FALLOCATE_PRESENT -DROCKSDB_MALLOC_USABLE_SIZE" CFLAGS+=" -DROCKSDB_PLATFORM_POSIX -DROCKSDB_LIB_IO_POSIX -DROCKSDB_FALLOCATE_PRESENT -DROCKSDB_MALLOC_USABLE_SIZE"
CXXFLAGS+=" $CFLAGS" CXXFLAGS+=" $CFLAGS"
EXEC_LDFLAGS=" $SNAPPY_LIBS $ZLIB_LIBS $BZIP_LIBS $LZ4_LIBS $ZSTD_LIBS $GFLAGS_LIBS $NUMA_LIB" EXEC_LDFLAGS=" $SNAPPY_LIBS $ZLIB_LIBS $BZIP_LIBS $LZ4_LIBS $ZSTD_LIBS $GFLAGS_LIBS $NUMA_LIB"

2
build_tools/fbcode_config4.8.1.sh
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@ -91,7 +91,7 @@ else
fi fi
CFLAGS+=" $DEPS_INCLUDE" CFLAGS+=" $DEPS_INCLUDE"
CFLAGS+=" -DROCKSDB_PLATFORM_POSIX -DROCKSDB_FALLOCATE_PRESENT -DROCKSDB_MALLOC_USABLE_SIZE" CFLAGS+=" -DROCKSDB_PLATFORM_POSIX -DROCKSDB_LIB_IO_POSIX -DROCKSDB_FALLOCATE_PRESENT -DROCKSDB_MALLOC_USABLE_SIZE"
CFLAGS+=" -DSNAPPY -DGFLAGS=google -DZLIB -DBZIP2 -DLZ4 -DZSTD -DNUMA" CFLAGS+=" -DSNAPPY -DGFLAGS=google -DZLIB -DBZIP2 -DLZ4 -DZSTD -DNUMA"
CXXFLAGS+=" $CFLAGS" CXXFLAGS+=" $CFLAGS"

214
include/posix/io_posix.h Normal file
View File

@ -0,0 +1,214 @@
// Copyright (c) 2013, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
//
// 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 <deque>
#include <set>
#include <dirent.h>
#include <pthread.h>
#include <string.h>
#include <sys/time.h>
#include <time.h>
#include <signal.h>
#include <algorithm>
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/mman.h>
#ifdef OS_LINUX
#include <sys/statfs.h>
#include <sys/syscall.h>
#endif
#if defined(OS_LINUX)
#include <linux/fs.h>
#endif
#include "rocksdb/env.h"
#include "util/sync_point.h"
#include "util/iostats_context_imp.h"
#include "util/coding.h"
#include "rocksdb/slice.h"
#include "port/port.h"
#include "util/logging.h"
#include "util/posix_logger.h"
#include "util/random.h"
#include "util/string_util.h"
#include "util/thread_status_updater.h"
#include "util/thread_status_util.h"
// For non linux platform, the following macros are used only as place
// holder.
#if !(defined OS_LINUX) && !(defined CYGWIN)
#define POSIX_FADV_NORMAL 0 /* [MC1] no further special treatment */
#define POSIX_FADV_RANDOM 1 /* [MC1] expect random page refs */
#define POSIX_FADV_SEQUENTIAL 2 /* [MC1] expect sequential page refs */
#define POSIX_FADV_WILLNEED 3 /* [MC1] will need these pages */
#define POSIX_FADV_DONTNEED 4 /* [MC1] dont need these pages */
#endif
namespace rocksdb {
static Status IOError(const std::string& context, int err_number) {
return Status::IOError(context, strerror(err_number));
}
class PosixSequentialFile : public SequentialFile {
private:
std::string filename_;
FILE* file_;
int fd_;
bool use_os_buffer_;
public:
PosixSequentialFile(const std::string& fname, FILE* f,
const EnvOptions& options);
virtual ~PosixSequentialFile();
virtual Status Read(size_t n, Slice* result, char* scratch) override;
virtual Status Skip(uint64_t n) override;
virtual Status InvalidateCache(size_t offset, size_t length) override;
};
class PosixRandomAccessFile : public RandomAccessFile {
private:
std::string filename_;
int fd_;
bool use_os_buffer_;
public:
PosixRandomAccessFile(const std::string& fname, int fd,
const EnvOptions& options);
virtual ~PosixRandomAccessFile();
virtual Status Read(uint64_t offset, size_t n, Slice* result,
char* scratch) const override;
#ifdef OS_LINUX
virtual size_t GetUniqueId(char* id, size_t max_size) const override;
#endif
virtual void Hint(AccessPattern pattern) override;
virtual Status InvalidateCache(size_t offset, size_t length) override;
};
class PosixWritableFile : public WritableFile {
private:
const std::string filename_;
int fd_;
uint64_t filesize_;
#ifdef ROCKSDB_FALLOCATE_PRESENT
bool allow_fallocate_;
bool fallocate_with_keep_size_;
#endif
public:
PosixWritableFile(const std::string& fname, int fd,
const EnvOptions& options);
~PosixWritableFile();
// Means Close() will properly take care of truncate
// and it does not need any additional information
virtual Status Truncate(uint64_t size) override { return Status::OK(); }
virtual Status Close() override;
virtual Status Append(const Slice& data) override;
virtual Status Flush() override;
virtual Status Sync() override;
virtual Status Fsync() override;
virtual bool IsSyncThreadSafe() const override;
virtual uint64_t GetFileSize() override;
virtual Status InvalidateCache(size_t offset, size_t length) override;
#ifdef ROCKSDB_FALLOCATE_PRESENT
virtual Status Allocate(off_t offset, off_t len) override;
virtual Status RangeSync(off_t offset, off_t nbytes) override;
virtual size_t GetUniqueId(char* id, size_t max_size) const override;
#endif
};
class PosixMmapReadableFile : public RandomAccessFile {
private:
int fd_;
std::string filename_;
void* mmapped_region_;
size_t length_;
public:
PosixMmapReadableFile(const int fd, const std::string& fname, void* base,
size_t length, const EnvOptions& options);
virtual ~PosixMmapReadableFile();
virtual Status Read(uint64_t offset, size_t n, Slice* result,
char* scratch) const override;
virtual Status InvalidateCache(size_t offset, size_t length) override;
};
class PosixMmapFile : public WritableFile {
private:
std::string filename_;
int fd_;
size_t page_size_;
size_t map_size_; // How much extra memory to map at a time
char* base_; // The mapped region
char* limit_; // Limit of the mapped region
char* dst_; // Where to write next (in range [base_,limit_])
char* last_sync_; // Where have we synced up to
uint64_t file_offset_; // Offset of base_ in file
#ifdef ROCKSDB_FALLOCATE_PRESENT
bool allow_fallocate_; // If false, fallocate calls are bypassed
bool fallocate_with_keep_size_;
#endif
// Roundup x to a multiple of y
static size_t Roundup(size_t x, size_t y) { return ((x + y - 1) / y) * y; }
size_t TruncateToPageBoundary(size_t s) {
s -= (s & (page_size_ - 1));
assert((s % page_size_) == 0);
return s;
}
Status MapNewRegion();
Status UnmapCurrentRegion();
Status Msync();
public:
PosixMmapFile(const std::string& fname, int fd, size_t page_size,
const EnvOptions& options);
~PosixMmapFile();
// Means Close() will properly take care of truncate
// and it does not need any additional information
virtual Status Truncate(uint64_t size) override { return Status::OK(); }
virtual Status Close() override;
virtual Status Append(const Slice& data) override;
virtual Status Flush() override;
virtual Status Sync() override;
virtual Status Fsync() override;
virtual uint64_t GetFileSize() override;
virtual Status InvalidateCache(size_t offset, size_t length) override;
#ifdef ROCKSDB_FALLOCATE_PRESENT
virtual Status Allocate(off_t offset, off_t len) override;
#endif
};
class PosixDirectory : public Directory {
public:
explicit PosixDirectory(int fd) : fd_(fd) {}
~PosixDirectory() { close(fd_); }
virtual Status Fsync() override {
if (fsync(fd_) == -1) {
return IOError("directory", errno);
}
return Status::OK();
}
private:
int fd_;
};
} // namespace rocksdb

1
src.mk
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@ -95,6 +95,7 @@ LIB_SOURCES = \
util/env.cc \ util/env.cc \
util/env_hdfs.cc \ util/env_hdfs.cc \
util/env_posix.cc \ util/env_posix.cc \
util/io_posix.cc \
util/file_util.cc \ util/file_util.cc \
util/file_reader_writer.cc \ util/file_reader_writer.cc \
util/filter_policy.cc \ util/filter_policy.cc \

742
util/env_posix.cc
View File

@ -7,43 +7,7 @@
// Use of this source code is governed by a BSD-style license that can be // 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. // found in the LICENSE file. See the AUTHORS file for names of contributors.
#include <deque> #include "posix/io_posix.h"
#include <set>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#ifdef OS_LINUX
#include <sys/statfs.h>
#include <sys/syscall.h>
#endif
#include <sys/time.h>
#include <sys/types.h>
#include <time.h>
#include <unistd.h>
#if defined(OS_LINUX)
#include <linux/fs.h>
#endif
#include <signal.h>
#include <algorithm>
#include "rocksdb/env.h"
#include "rocksdb/slice.h"
#include "port/port.h"
#include "util/coding.h"
#include "util/logging.h"
#include "util/posix_logger.h"
#include "util/random.h"
#include "util/iostats_context_imp.h"
#include "util/string_util.h"
#include "util/sync_point.h"
#include "util/thread_status_updater.h"
#include "util/thread_status_util.h"
// Get nano time includes // Get nano time includes
#if defined(OS_LINUX) || defined(OS_FREEBSD) #if defined(OS_LINUX) || defined(OS_FREEBSD)
@ -64,31 +28,10 @@
#define EXT4_SUPER_MAGIC 0xEF53 #define EXT4_SUPER_MAGIC 0xEF53
#endif #endif
// For non linux platform, the following macros are used only as place
// holder.
#if !(defined OS_LINUX) && !(defined CYGWIN)
#define POSIX_FADV_NORMAL 0 /* [MC1] no further special treatment */
#define POSIX_FADV_RANDOM 1 /* [MC1] expect random page refs */
#define POSIX_FADV_SEQUENTIAL 2 /* [MC1] expect sequential page refs */
#define POSIX_FADV_WILLNEED 3 /* [MC1] will need these pages */
#define POSIX_FADV_DONTNEED 4 /* [MC1] dont need these pages */
#endif
namespace rocksdb { namespace rocksdb {
namespace { namespace {
// A wrapper for fadvise, if the platform doesn't support fadvise,
// it will simply return Status::NotSupport.
int Fadvise(int fd, off_t offset, size_t len, int advice) {
#ifdef OS_LINUX
return posix_fadvise(fd, offset, len, advice);
#else
return 0; // simply do nothing.
#endif
}
ThreadStatusUpdater* CreateThreadStatusUpdater() { ThreadStatusUpdater* CreateThreadStatusUpdater() {
return new ThreadStatusUpdater(); return new ThreadStatusUpdater();
} }
@ -97,677 +40,6 @@ ThreadStatusUpdater* CreateThreadStatusUpdater() {
static std::set<std::string> lockedFiles; static std::set<std::string> lockedFiles;
static port::Mutex mutex_lockedFiles; static port::Mutex mutex_lockedFiles;
static Status IOError(const std::string& context, int err_number) {
return Status::IOError(context, strerror(err_number));
}
#if defined(OS_LINUX)
namespace {
static size_t GetUniqueIdFromFile(int fd, char* id, size_t max_size) {
if (max_size < kMaxVarint64Length*3) {
return 0;
}
struct stat buf;
int result = fstat(fd, &buf);
if (result == -1) {
return 0;
}
long version = 0;
result = ioctl(fd, FS_IOC_GETVERSION, &version);
if (result == -1) {
return 0;
}
uint64_t uversion = (uint64_t)version;
char* rid = id;
rid = EncodeVarint64(rid, buf.st_dev);
rid = EncodeVarint64(rid, buf.st_ino);
rid = EncodeVarint64(rid, uversion);
assert(rid >= id);
return static_cast<size_t>(rid-id);
}
}
#endif
class PosixSequentialFile: public SequentialFile {
private:
std::string filename_;
FILE* file_;
int fd_;
bool use_os_buffer_;
public:
PosixSequentialFile(const std::string& fname, FILE* f,
const EnvOptions& options)
: filename_(fname), file_(f), fd_(fileno(f)),
use_os_buffer_(options.use_os_buffer) {
}
virtual ~PosixSequentialFile() { fclose(file_); }
virtual Status Read(size_t n, Slice* result, char* scratch) override {
Status s;
size_t r = 0;
do {
r = fread_unlocked(scratch, 1, n, file_);
} while (r == 0 && ferror(file_) && errno == EINTR);
*result = Slice(scratch, r);
if (r < n) {
if (feof(file_)) {
// We leave status as ok if we hit the end of the file
// We also clear the error so that the reads can continue
// if a new data is written to the file
clearerr(file_);
} else {
// A partial read with an error: return a non-ok status
s = IOError(filename_, errno);
}
}
if (!use_os_buffer_) {
// we need to fadvise away the entire range of pages because
// we do not want readahead pages to be cached.
Fadvise(fd_, 0, 0, POSIX_FADV_DONTNEED); // free OS pages
}
return s;
}
virtual Status Skip(uint64_t n) override {
if (fseek(file_, static_cast<long int>(n), SEEK_CUR)) {
return IOError(filename_, errno);
}
return Status::OK();
}
virtual Status InvalidateCache(size_t offset, size_t length) override {
#ifndef OS_LINUX
return Status::OK();
#else
// free OS pages
int ret = Fadvise(fd_, offset, length, POSIX_FADV_DONTNEED);
if (ret == 0) {
return Status::OK();
}
return IOError(filename_, errno);
#endif
}
};
// pread() based random-access
class PosixRandomAccessFile: public RandomAccessFile {
private:
std::string filename_;
int fd_;
bool use_os_buffer_;
public:
PosixRandomAccessFile(const std::string& fname, int fd,
const EnvOptions& options)
: filename_(fname), fd_(fd), use_os_buffer_(options.use_os_buffer) {
assert(!options.use_mmap_reads || sizeof(void*) < 8);
}
virtual ~PosixRandomAccessFile() { close(fd_); }
virtual Status Read(uint64_t offset, size_t n, Slice* result,
char* scratch) const override {
Status s;
ssize_t r = -1;
size_t left = n;
char* ptr = scratch;
while (left > 0) {
r = pread(fd_, ptr, left, static_cast<off_t>(offset));
if (r <= 0) {
if (errno == EINTR) {
continue;
}
break;
}
ptr += r;
offset += r;
left -= r;
}
*result = Slice(scratch, (r < 0) ? 0 : n - left);
if (r < 0) {
// An error: return a non-ok status
s = IOError(filename_, errno);
}
if (!use_os_buffer_) {
// we need to fadvise away the entire range of pages because
// we do not want readahead pages to be cached.
Fadvise(fd_, 0, 0, POSIX_FADV_DONTNEED); // free OS pages
}
return s;
}
#ifdef OS_LINUX
virtual size_t GetUniqueId(char* id, size_t max_size) const override {
return GetUniqueIdFromFile(fd_, id, max_size);
}
#endif
virtual void Hint(AccessPattern pattern) override {
switch(pattern) {
case NORMAL:
Fadvise(fd_, 0, 0, POSIX_FADV_NORMAL);
break;
case RANDOM:
Fadvise(fd_, 0, 0, POSIX_FADV_RANDOM);
break;
case SEQUENTIAL:
Fadvise(fd_, 0, 0, POSIX_FADV_SEQUENTIAL);
break;
case WILLNEED:
Fadvise(fd_, 0, 0, POSIX_FADV_WILLNEED);
break;
case DONTNEED:
Fadvise(fd_, 0, 0, POSIX_FADV_DONTNEED);
break;
default:
assert(false);
break;
}
}
virtual Status InvalidateCache(size_t offset, size_t length) override {
#ifndef OS_LINUX
return Status::OK();
#else
// free OS pages
int ret = Fadvise(fd_, offset, length, POSIX_FADV_DONTNEED);
if (ret == 0) {
return Status::OK();
}
return IOError(filename_, errno);
#endif
}
};
// mmap() based random-access
class PosixMmapReadableFile: public RandomAccessFile {
private:
int fd_;
std::string filename_;
void* mmapped_region_;
size_t length_;
public:
// base[0,length-1] contains the mmapped contents of the file.
PosixMmapReadableFile(const int fd, const std::string& fname,
void* base, size_t length,
const EnvOptions& options)
: fd_(fd), filename_(fname), mmapped_region_(base), length_(length) {
fd_ = fd_ + 0; // suppress the warning for used variables
assert(options.use_mmap_reads);
assert(options.use_os_buffer);
}
virtual ~PosixMmapReadableFile() {
int ret = munmap(mmapped_region_, length_);
if (ret != 0) {
fprintf(stdout, "failed to munmap %p length %" ROCKSDB_PRIszt " \n",
mmapped_region_, length_);
}
}
virtual Status Read(uint64_t offset, size_t n, Slice* result,
char* scratch) const override {
Status s;
if (offset > length_) {
*result = Slice();
return IOError(filename_, EINVAL);
} else if (offset + n > length_) {
n = static_cast<size_t>(length_ - offset);
}
*result = Slice(reinterpret_cast<char*>(mmapped_region_) + offset, n);
return s;
}
virtual Status InvalidateCache(size_t offset, size_t length) override {
#ifndef OS_LINUX
return Status::OK();
#else
// free OS pages
int ret = Fadvise(fd_, offset, length, POSIX_FADV_DONTNEED);
if (ret == 0) {
return Status::OK();
}
return IOError(filename_, errno);
#endif
}
};
// We preallocate up to an extra megabyte and use memcpy to append new
// data to the file. This is safe since we either properly close the
// file before reading from it, or for log files, the reading code
// knows enough to skip zero suffixes.
class PosixMmapFile : public WritableFile {
private:
std::string filename_;
int fd_;
size_t page_size_;
size_t map_size_; // How much extra memory to map at a time
char* base_; // The mapped region
char* limit_; // Limit of the mapped region
char* dst_; // Where to write next (in range [base_,limit_])
char* last_sync_; // Where have we synced up to
uint64_t file_offset_; // Offset of base_ in file
#ifdef ROCKSDB_FALLOCATE_PRESENT
bool allow_fallocate_; // If false, fallocate calls are bypassed
bool fallocate_with_keep_size_;
#endif
// Roundup x to a multiple of y
static size_t Roundup(size_t x, size_t y) {
return ((x + y - 1) / y) * y;
}
size_t TruncateToPageBoundary(size_t s) {
s -= (s & (page_size_ - 1));
assert((s % page_size_) == 0);
return s;
}
Status UnmapCurrentRegion() {
TEST_KILL_RANDOM("PosixMmapFile::UnmapCurrentRegion:0", rocksdb_kill_odds);
if (base_ != nullptr) {
int munmap_status = munmap(base_, limit_ - base_);
if (munmap_status != 0) {
return IOError(filename_, munmap_status);
}
file_offset_ += limit_ - base_;
base_ = nullptr;
limit_ = nullptr;
last_sync_ = nullptr;
dst_ = nullptr;
// Increase the amount we map the next time, but capped at 1MB
if (map_size_ < (1<<20)) {
map_size_ *= 2;
}
}
return Status::OK();
}
Status MapNewRegion() {
#ifdef ROCKSDB_FALLOCATE_PRESENT
assert(base_ == nullptr);
TEST_KILL_RANDOM("PosixMmapFile::UnmapCurrentRegion:0", rocksdb_kill_odds);
// we can't fallocate with FALLOC_FL_KEEP_SIZE here
if (allow_fallocate_) {
IOSTATS_TIMER_GUARD(allocate_nanos);
int alloc_status = fallocate(fd_, 0, file_offset_, map_size_);
if (alloc_status != 0) {
// fallback to posix_fallocate
alloc_status = posix_fallocate(fd_, file_offset_, map_size_);
}
if (alloc_status != 0) {
return Status::IOError("Error allocating space to file : " + filename_ +
"Error : " + strerror(alloc_status));
}
}
TEST_KILL_RANDOM("PosixMmapFile::Append:1", rocksdb_kill_odds);
void* ptr = mmap(nullptr, map_size_, PROT_READ | PROT_WRITE, MAP_SHARED,
fd_, file_offset_);
if (ptr == MAP_FAILED) {
return Status::IOError("MMap failed on " + filename_);
}
TEST_KILL_RANDOM("PosixMmapFile::Append:2", rocksdb_kill_odds);
base_ = reinterpret_cast<char*>(ptr);
limit_ = base_ + map_size_;
dst_ = base_;
last_sync_ = base_;
return Status::OK();
#else
return Status::NotSupported("This platform doesn't support fallocate()");
#endif
}
Status Msync() {
if (dst_ == last_sync_) {
return Status::OK();
}
// Find the beginnings of the pages that contain the first and last
// bytes to be synced.
size_t p1 = TruncateToPageBoundary(last_sync_ - base_);
size_t p2 = TruncateToPageBoundary(dst_ - base_ - 1);
last_sync_ = dst_;
TEST_KILL_RANDOM("PosixMmapFile::Msync:0", rocksdb_kill_odds);
if (msync(base_ + p1, p2 - p1 + page_size_, MS_SYNC) < 0) {
return IOError(filename_, errno);
}
return Status::OK();
}
public:
PosixMmapFile(const std::string& fname, int fd, size_t page_size,
const EnvOptions& options)
: filename_(fname),
fd_(fd),
page_size_(page_size),
map_size_(Roundup(65536, page_size)),
base_(nullptr),
limit_(nullptr),
dst_(nullptr),
last_sync_(nullptr),
file_offset_(0) {
#ifdef ROCKSDB_FALLOCATE_PRESENT
allow_fallocate_ = options.allow_fallocate;
fallocate_with_keep_size_ = options.fallocate_with_keep_size;
#endif
assert((page_size & (page_size - 1)) == 0);
assert(options.use_mmap_writes);
}
~PosixMmapFile() {
if (fd_ >= 0) {
PosixMmapFile::Close();
}
}
virtual Status Append(const Slice& data) override {
const char* src = data.data();
size_t left = data.size();
while (left > 0) {
assert(base_ <= dst_);
assert(dst_ <= limit_);
size_t avail = limit_ - dst_;
if (avail == 0) {
Status s = UnmapCurrentRegion();
if (!s.ok()) {
return s;
}
s = MapNewRegion();
if (!s.ok()) {
return s;
}
TEST_KILL_RANDOM("PosixMmapFile::Append:0", rocksdb_kill_odds);
}
size_t n = (left <= avail) ? left : avail;
memcpy(dst_, src, n);
dst_ += n;
src += n;
left -= n;
}
return Status::OK();
}
// Means Close() will properly take care of truncate
// and it does not need any additional information
virtual Status Truncate(uint64_t size) override {
return Status::OK();
}
virtual Status Close() override {
Status s;
size_t unused = limit_ - dst_;
s = UnmapCurrentRegion();
if (!s.ok()) {
s = IOError(filename_, errno);
} else if (unused > 0) {
// Trim the extra space at the end of the file
if (ftruncate(fd_, file_offset_ - unused) < 0) {
s = IOError(filename_, errno);
}
}
if (close(fd_) < 0) {
if (s.ok()) {
s = IOError(filename_, errno);
}
}
fd_ = -1;
base_ = nullptr;
limit_ = nullptr;
return s;
}
virtual Status Flush() override {
return Status::OK();
}
virtual Status Sync() override {
if (fdatasync(fd_) < 0) {
return IOError(filename_, errno);
}
return Msync();
}
/**
* Flush data as well as metadata to stable storage.
*/
virtual Status Fsync() override {
if (fsync(fd_) < 0) {
return IOError(filename_, errno);
}
return Msync();
}
/**
* Get the size of valid data in the file. This will not match the
* size that is returned from the filesystem because we use mmap
* to extend file by map_size every time.
*/
virtual uint64_t GetFileSize() override {
size_t used = dst_ - base_;
return file_offset_ + used;
}
virtual Status InvalidateCache(size_t offset, size_t length) override {
#ifndef OS_LINUX
return Status::OK();
#else
// free OS pages
int ret = Fadvise(fd_, offset, length, POSIX_FADV_DONTNEED);
if (ret == 0) {
return Status::OK();
}
return IOError(filename_, errno);
#endif
}
#ifdef ROCKSDB_FALLOCATE_PRESENT
virtual Status Allocate(off_t offset, off_t len) override {
TEST_KILL_RANDOM("PosixMmapFile::Allocate:0", rocksdb_kill_odds);
int alloc_status = 0;
if (allow_fallocate_) {
alloc_status =
fallocate(fd_, fallocate_with_keep_size_ ? FALLOC_FL_KEEP_SIZE : 0,
offset, len);
}
if (alloc_status == 0) {
return Status::OK();
} else {
return IOError(filename_, errno);
}
}
#endif
};
// Use posix write to write data to a file.
class PosixWritableFile : public WritableFile {
private:
const std::string filename_;
int fd_;
uint64_t filesize_;
#ifdef ROCKSDB_FALLOCATE_PRESENT
bool allow_fallocate_;
bool fallocate_with_keep_size_;
#endif
public:
PosixWritableFile(const std::string& fname, int fd, const EnvOptions& options)
: filename_(fname), fd_(fd), filesize_(0) {
#ifdef ROCKSDB_FALLOCATE_PRESENT
allow_fallocate_ = options.allow_fallocate;
fallocate_with_keep_size_ = options.fallocate_with_keep_size;
#endif
assert(!options.use_mmap_writes);
}
~PosixWritableFile() {
if (fd_ >= 0) {
PosixWritableFile::Close();
}
}
virtual Status Append(const Slice& data) override {
const char* src = data.data();
size_t left = data.size();
while (left != 0) {
ssize_t done = write(fd_, src, left);
if (done < 0) {
if (errno == EINTR) {
continue;
}
return IOError(filename_, errno);
}
left -= done;
src += done;
}
filesize_ += data.size();
return Status::OK();
}
// Means Close() will properly take care of truncate
// and it does not need any additional information
virtual Status Truncate(uint64_t size) override {
return Status::OK();
}
virtual Status Close() override {
Status s;
size_t block_size;
size_t last_allocated_block;
GetPreallocationStatus(&block_size, &last_allocated_block);
if (last_allocated_block > 0) {
// trim the extra space preallocated at the end of the file
// NOTE(ljin): we probably don't want to surface failure as an IOError,
// but it will be nice to log these errors.
int dummy __attribute__((unused));
dummy = ftruncate(fd_, filesize_);
#ifdef ROCKSDB_FALLOCATE_PRESENT
// in some file systems, ftruncate only trims trailing space if the
// new file size is smaller than the current size. Calling fallocate
// with FALLOC_FL_PUNCH_HOLE flag to explicitly release these unused
// blocks. FALLOC_FL_PUNCH_HOLE is supported on at least the following
// filesystems:
// XFS (since Linux 2.6.38)
// ext4 (since Linux 3.0)
// Btrfs (since Linux 3.7)
// tmpfs (since Linux 3.5)
// We ignore error since failure of this operation does not affect
// correctness.
IOSTATS_TIMER_GUARD(allocate_nanos);
if (allow_fallocate_) {
fallocate(fd_, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, filesize_,
block_size * last_allocated_block - filesize_);
}
#endif
}
if (close(fd_) < 0) {
s = IOError(filename_, errno);
}
fd_ = -1;
return s;
}
// write out the cached data to the OS cache
virtual Status Flush() override {
return Status::OK();
}
virtual Status Sync() override {
if (fdatasync(fd_) < 0) {
return IOError(filename_, errno);
}
return Status::OK();
}
virtual Status Fsync() override {
if (fsync(fd_) < 0) {
return IOError(filename_, errno);
}
return Status::OK();
}
virtual bool IsSyncThreadSafe() const override {
return true;
}
virtual uint64_t GetFileSize() override { return filesize_; }
virtual Status InvalidateCache(size_t offset, size_t length) override {
#ifndef OS_LINUX
return Status::OK();
#else
// free OS pages
int ret = Fadvise(fd_, offset, length, POSIX_FADV_DONTNEED);
if (ret == 0) {
return Status::OK();
}
return IOError(filename_, errno);
#endif
}
#ifdef ROCKSDB_FALLOCATE_PRESENT
virtual Status Allocate(off_t offset, off_t len) override {
TEST_KILL_RANDOM("PosixWritableFile::Allocate:0", rocksdb_kill_odds);
IOSTATS_TIMER_GUARD(allocate_nanos);
int alloc_status = 0;
if (allow_fallocate_) {
alloc_status =
fallocate(fd_, fallocate_with_keep_size_ ? FALLOC_FL_KEEP_SIZE : 0,
offset, len);
}
if (alloc_status == 0) {
return Status::OK();
} else {
return IOError(filename_, errno);
}
}
virtual Status RangeSync(off_t offset, off_t nbytes) override {
if (sync_file_range(fd_, offset, nbytes, SYNC_FILE_RANGE_WRITE) == 0) {
return Status::OK();
} else {
return IOError(filename_, errno);
}
}
virtual size_t GetUniqueId(char* id, size_t max_size) const override {
return GetUniqueIdFromFile(fd_, id, max_size);
}
#endif
};
class PosixDirectory : public Directory {
public:
explicit PosixDirectory(int fd) : fd_(fd) {}
~PosixDirectory() {
close(fd_);
}
virtual Status Fsync() override {
if (fsync(fd_) == -1) {
return IOError("directory", errno);
}
return Status::OK();
}
private:
int fd_;
};
static int LockOrUnlock(const std::string& fname, int fd, bool lock) { static int LockOrUnlock(const std::string& fname, int fd, bool lock) {
mutex_lockedFiles.Lock(); mutex_lockedFiles.Lock();
if (lock) { if (lock) {
@ -806,12 +78,6 @@ static int LockOrUnlock(const std::string& fname, int fd, bool lock) {
return value; return value;
} }
class PosixFileLock : public FileLock {
public:
int fd_;
std::string filename;
};
void PthreadCall(const char* label, int result) { void PthreadCall(const char* label, int result) {
if (result != 0) { if (result != 0) {
fprintf(stderr, "pthread %s: %s\n", label, strerror(result)); fprintf(stderr, "pthread %s: %s\n", label, strerror(result));
@ -819,6 +85,12 @@ void PthreadCall(const char* label, int result) {
} }
} }
class PosixFileLock : public FileLock {
public:
int fd_;
std::string filename;
};
class PosixEnv : public Env { class PosixEnv : public Env {
public: public:
PosixEnv(); PosixEnv();

614
util/io_posix.cc Normal file
View File

@ -0,0 +1,614 @@
// Copyright (c) 2013, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
//
// 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.
#ifdef ROCKSDB_LIB_IO_POSIX
#include "posix/io_posix.h"
namespace rocksdb {
// A wrapper for fadvise, if the platform doesn't support fadvise,
// it will simply return Status::NotSupport.
int Fadvise(int fd, off_t offset, size_t len, int advice) {
#ifdef OS_LINUX
return posix_fadvise(fd, offset, len, advice);
#else
return 0; // simply do nothing.
#endif
}
/*
* PosixSequentialFile
*/
PosixSequentialFile::PosixSequentialFile(const std::string& fname, FILE* f,
const EnvOptions& options)
: filename_(fname),
file_(f),
fd_(fileno(f)),
use_os_buffer_(options.use_os_buffer) {}
PosixSequentialFile::~PosixSequentialFile() { fclose(file_); }
Status PosixSequentialFile::Read(size_t n, Slice* result, char* scratch) {
Status s;
size_t r = 0;
do {
r = fread_unlocked(scratch, 1, n, file_);
} while (r == 0 && ferror(file_) && errno == EINTR);
*result = Slice(scratch, r);
if (r < n) {
if (feof(file_)) {
// We leave status as ok if we hit the end of the file
// We also clear the error so that the reads can continue
// if a new data is written to the file
clearerr(file_);
} else {
// A partial read with an error: return a non-ok status
s = IOError(filename_, errno);
}
}
if (!use_os_buffer_) {
// we need to fadvise away the entire range of pages because
// we do not want readahead pages to be cached.
Fadvise(fd_, 0, 0, POSIX_FADV_DONTNEED); // free OS pages
}
return s;
}
Status PosixSequentialFile::Skip(uint64_t n) {
if (fseek(file_, static_cast<long int>(n), SEEK_CUR)) {
return IOError(filename_, errno);
}
return Status::OK();
}
Status PosixSequentialFile::InvalidateCache(size_t offset, size_t length) {
#ifndef OS_LINUX
return Status::OK();
#else
// free OS pages
int ret = Fadvise(fd_, offset, length, POSIX_FADV_DONTNEED);
if (ret == 0) {
return Status::OK();
}
return IOError(filename_, errno);
#endif
}
#if defined(OS_LINUX)
namespace {
static size_t GetUniqueIdFromFile(int fd, char* id, size_t max_size) {
if (max_size < kMaxVarint64Length * 3) {
return 0;
}
struct stat buf;
int result = fstat(fd, &buf);
if (result == -1) {
return 0;
}
long version = 0;
result = ioctl(fd, FS_IOC_GETVERSION, &version);
if (result == -1) {
return 0;
}
uint64_t uversion = (uint64_t)version;
char* rid = id;
rid = EncodeVarint64(rid, buf.st_dev);
rid = EncodeVarint64(rid, buf.st_ino);
rid = EncodeVarint64(rid, uversion);
assert(rid >= id);
return static_cast<size_t>(rid - id);
}
}
#endif
/*
* PosixRandomAccessFile
*
* pread() based random-access
*/
PosixRandomAccessFile::PosixRandomAccessFile(const std::string& fname, int fd,
const EnvOptions& options)
: filename_(fname), fd_(fd), use_os_buffer_(options.use_os_buffer) {
assert(!options.use_mmap_reads || sizeof(void*) < 8);
}
PosixRandomAccessFile::~PosixRandomAccessFile() { close(fd_); }
Status PosixRandomAccessFile::Read(uint64_t offset, size_t n, Slice* result,
char* scratch) const {
Status s;
ssize_t r = -1;
size_t left = n;
char* ptr = scratch;
while (left > 0) {
r = pread(fd_, ptr, left, static_cast<off_t>(offset));
if (r <= 0) {
if (errno == EINTR) {
continue;
}
break;
}
ptr += r;
offset += r;
left -= r;
}
*result = Slice(scratch, (r < 0) ? 0 : n - left);
if (r < 0) {
// An error: return a non-ok status
s = IOError(filename_, errno);
}
if (!use_os_buffer_) {
// we need to fadvise away the entire range of pages because
// we do not want readahead pages to be cached.
Fadvise(fd_, 0, 0, POSIX_FADV_DONTNEED); // free OS pages
}
return s;
}
#ifdef OS_LINUX
size_t PosixRandomAccessFile::GetUniqueId(char* id, size_t max_size) const {
return GetUniqueIdFromFile(fd_, id, max_size);
}
#endif
void PosixRandomAccessFile::Hint(AccessPattern pattern) {
switch (pattern) {
case NORMAL:
Fadvise(fd_, 0, 0, POSIX_FADV_NORMAL);
break;
case RANDOM:
Fadvise(fd_, 0, 0, POSIX_FADV_RANDOM);
break;
case SEQUENTIAL:
Fadvise(fd_, 0, 0, POSIX_FADV_SEQUENTIAL);
break;
case WILLNEED:
Fadvise(fd_, 0, 0, POSIX_FADV_WILLNEED);
break;
case DONTNEED:
Fadvise(fd_, 0, 0, POSIX_FADV_DONTNEED);
break;
default:
assert(false);
break;
}
}
Status PosixRandomAccessFile::InvalidateCache(size_t offset, size_t length) {
#ifndef OS_LINUX
return Status::OK();
#else
// free OS pages
int ret = Fadvise(fd_, offset, length, POSIX_FADV_DONTNEED);
if (ret == 0) {
return Status::OK();
}
return IOError(filename_, errno);
#endif
}
/*
* PosixMmapReadableFile
*
* mmap() based random-access
*/
// base[0,length-1] contains the mmapped contents of the file.
PosixMmapReadableFile::PosixMmapReadableFile(const int fd,
const std::string& fname,
void* base, size_t length,
const EnvOptions& options)
: fd_(fd), filename_(fname), mmapped_region_(base), length_(length) {
fd_ = fd_ + 0; // suppress the warning for used variables
assert(options.use_mmap_reads);
assert(options.use_os_buffer);
}
PosixMmapReadableFile::~PosixMmapReadableFile() {
int ret = munmap(mmapped_region_, length_);
if (ret != 0) {
fprintf(stdout, "failed to munmap %p length %" ROCKSDB_PRIszt " \n",
mmapped_region_, length_);
}
}
Status PosixMmapReadableFile::Read(uint64_t offset, size_t n, Slice* result,
char* scratch) const {
Status s;
if (offset > length_) {
*result = Slice();
return IOError(filename_, EINVAL);
} else if (offset + n > length_) {
n = static_cast<size_t>(length_ - offset);
}
*result = Slice(reinterpret_cast<char*>(mmapped_region_) + offset, n);
return s;
}
Status PosixMmapReadableFile::InvalidateCache(size_t offset, size_t length) {
#ifndef OS_LINUX
return Status::OK();
#else
// free OS pages
int ret = Fadvise(fd_, offset, length, POSIX_FADV_DONTNEED);
if (ret == 0) {
return Status::OK();
}
return IOError(filename_, errno);
#endif
}
/*
* PosixMmapFile
*
* We preallocate up to an extra megabyte and use memcpy to append new
* data to the file. This is safe since we either properly close the
* file before reading from it, or for log files, the reading code
* knows enough to skip zero suffixes.
*/
Status PosixMmapFile::UnmapCurrentRegion() {
TEST_KILL_RANDOM("PosixMmapFile::UnmapCurrentRegion:0", rocksdb_kill_odds);
if (base_ != nullptr) {
int munmap_status = munmap(base_, limit_ - base_);
if (munmap_status != 0) {
return IOError(filename_, munmap_status);
}
file_offset_ += limit_ - base_;
base_ = nullptr;
limit_ = nullptr;
last_sync_ = nullptr;
dst_ = nullptr;
// Increase the amount we map the next time, but capped at 1MB
if (map_size_ < (1 << 20)) {
map_size_ *= 2;
}
}
return Status::OK();
}
Status PosixMmapFile::MapNewRegion() {
#ifdef ROCKSDB_FALLOCATE_PRESENT
assert(base_ == nullptr);
TEST_KILL_RANDOM("PosixMmapFile::UnmapCurrentRegion:0", rocksdb_kill_odds);
// we can't fallocate with FALLOC_FL_KEEP_SIZE here
if (allow_fallocate_) {
IOSTATS_TIMER_GUARD(allocate_nanos);
int alloc_status = fallocate(fd_, 0, file_offset_, map_size_);
if (alloc_status != 0) {
// fallback to posix_fallocate
alloc_status = posix_fallocate(fd_, file_offset_, map_size_);
}
if (alloc_status != 0) {
return Status::IOError("Error allocating space to file : " + filename_ +
"Error : " + strerror(alloc_status));
}
}
TEST_KILL_RANDOM("PosixMmapFile::Append:1", rocksdb_kill_odds);
void* ptr = mmap(nullptr, map_size_, PROT_READ | PROT_WRITE, MAP_SHARED, fd_,
file_offset_);
if (ptr == MAP_FAILED) {
return Status::IOError("MMap failed on " + filename_);
}
TEST_KILL_RANDOM("PosixMmapFile::Append:2", rocksdb_kill_odds);
base_ = reinterpret_cast<char*>(ptr);
limit_ = base_ + map_size_;
dst_ = base_;
last_sync_ = base_;
return Status::OK();
#else
return Status::NotSupported("This platform doesn't support fallocate()");
#endif
}
Status PosixMmapFile::Msync() {
if (dst_ == last_sync_) {
return Status::OK();
}
// Find the beginnings of the pages that contain the first and last
// bytes to be synced.
size_t p1 = TruncateToPageBoundary(last_sync_ - base_);
size_t p2 = TruncateToPageBoundary(dst_ - base_ - 1);
last_sync_ = dst_;
TEST_KILL_RANDOM("PosixMmapFile::Msync:0", rocksdb_kill_odds);
if (msync(base_ + p1, p2 - p1 + page_size_, MS_SYNC) < 0) {
return IOError(filename_, errno);
}
return Status::OK();
}
PosixMmapFile::PosixMmapFile(const std::string& fname, int fd, size_t page_size,
const EnvOptions& options)
: filename_(fname),
fd_(fd),
page_size_(page_size),
map_size_(Roundup(65536, page_size)),
base_(nullptr),
limit_(nullptr),
dst_(nullptr),
last_sync_(nullptr),
file_offset_(0) {
#ifdef ROCKSDB_FALLOCATE_PRESENT
allow_fallocate_ = options.allow_fallocate;
fallocate_with_keep_size_ = options.fallocate_with_keep_size;
#endif
assert((page_size & (page_size - 1)) == 0);
assert(options.use_mmap_writes);
}
PosixMmapFile::~PosixMmapFile() {
if (fd_ >= 0) {
PosixMmapFile::Close();
}
}
Status PosixMmapFile::Append(const Slice& data) {
const char* src = data.data();
size_t left = data.size();
while (left > 0) {
assert(base_ <= dst_);
assert(dst_ <= limit_);
size_t avail = limit_ - dst_;
if (avail == 0) {
Status s = UnmapCurrentRegion();
if (!s.ok()) {
return s;
}
s = MapNewRegion();
if (!s.ok()) {
return s;
}
TEST_KILL_RANDOM("PosixMmapFile::Append:0", rocksdb_kill_odds);
}
size_t n = (left <= avail) ? left : avail;
memcpy(dst_, src, n);
dst_ += n;
src += n;
left -= n;
}
return Status::OK();
}
Status PosixMmapFile::Close() {
Status s;
size_t unused = limit_ - dst_;
s = UnmapCurrentRegion();
if (!s.ok()) {
s = IOError(filename_, errno);
} else if (unused > 0) {
// Trim the extra space at the end of the file
if (ftruncate(fd_, file_offset_ - unused) < 0) {
s = IOError(filename_, errno);
}
}
if (close(fd_) < 0) {
if (s.ok()) {
s = IOError(filename_, errno);
}
}
fd_ = -1;
base_ = nullptr;
limit_ = nullptr;
return s;
}
Status PosixMmapFile::Flush() { return Status::OK(); }
Status PosixMmapFile::Sync() {
if (fdatasync(fd_) < 0) {
return IOError(filename_, errno);
}
return Msync();
}
/**
* Flush data as well as metadata to stable storage.
*/
Status PosixMmapFile::Fsync() {
if (fsync(fd_) < 0) {
return IOError(filename_, errno);
}
return Msync();
}
/**
* Get the size of valid data in the file. This will not match the
* size that is returned from the filesystem because we use mmap
* to extend file by map_size every time.
*/
uint64_t PosixMmapFile::GetFileSize() {
size_t used = dst_ - base_;
return file_offset_ + used;
}
Status PosixMmapFile::InvalidateCache(size_t offset, size_t length) {
#ifndef OS_LINUX
return Status::OK();
#else
// free OS pages
int ret = Fadvise(fd_, offset, length, POSIX_FADV_DONTNEED);
if (ret == 0) {
return Status::OK();
}
return IOError(filename_, errno);
#endif
}
#ifdef ROCKSDB_FALLOCATE_PRESENT
Status PosixMmapFile::Allocate(off_t offset, off_t len) {
TEST_KILL_RANDOM("PosixMmapFile::Allocate:0", rocksdb_kill_odds);
int alloc_status = 0;
if (allow_fallocate_) {
alloc_status = fallocate(
fd_, fallocate_with_keep_size_ ? FALLOC_FL_KEEP_SIZE : 0, offset, len);
}
if (alloc_status == 0) {
return Status::OK();
} else {
return IOError(filename_, errno);
}
}
#endif
/*
* PosixWritableFile
*
* Use posix write to write data to a file.
*/
PosixWritableFile::PosixWritableFile(const std::string& fname, int fd,
const EnvOptions& options)
: filename_(fname), fd_(fd), filesize_(0) {
#ifdef ROCKSDB_FALLOCATE_PRESENT
allow_fallocate_ = options.allow_fallocate;
fallocate_with_keep_size_ = options.fallocate_with_keep_size;
#endif
assert(!options.use_mmap_writes);
}
PosixWritableFile::~PosixWritableFile() {
if (fd_ >= 0) {
PosixWritableFile::Close();
}
}
Status PosixWritableFile::Append(const Slice& data) {
const char* src = data.data();
size_t left = data.size();
while (left != 0) {
ssize_t done = write(fd_, src, left);
if (done < 0) {
if (errno == EINTR) {
continue;
}
return IOError(filename_, errno);
}
left -= done;
src += done;
}
filesize_ += data.size();
return Status::OK();
}
Status PosixWritableFile::Close() {
Status s;
size_t block_size;
size_t last_allocated_block;
GetPreallocationStatus(&block_size, &last_allocated_block);
if (last_allocated_block > 0) {
// trim the extra space preallocated at the end of the file
// NOTE(ljin): we probably don't want to surface failure as an IOError,
// but it will be nice to log these errors.
int dummy __attribute__((unused));
dummy = ftruncate(fd_, filesize_);
#ifdef ROCKSDB_FALLOCATE_PRESENT
// in some file systems, ftruncate only trims trailing space if the
// new file size is smaller than the current size. Calling fallocate
// with FALLOC_FL_PUNCH_HOLE flag to explicitly release these unused
// blocks. FALLOC_FL_PUNCH_HOLE is supported on at least the following
// filesystems:
// XFS (since Linux 2.6.38)
// ext4 (since Linux 3.0)
// Btrfs (since Linux 3.7)
// tmpfs (since Linux 3.5)
// We ignore error since failure of this operation does not affect
// correctness.
IOSTATS_TIMER_GUARD(allocate_nanos);
if (allow_fallocate_) {
fallocate(fd_, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, filesize_,
block_size * last_allocated_block - filesize_);
}
#endif
}
if (close(fd_) < 0) {
s = IOError(filename_, errno);
}
fd_ = -1;
return s;
}
// write out the cached data to the OS cache
Status PosixWritableFile::Flush() { return Status::OK(); }
Status PosixWritableFile::Sync() {
if (fdatasync(fd_) < 0) {
return IOError(filename_, errno);
}
return Status::OK();
}
Status PosixWritableFile::Fsync() {
if (fsync(fd_) < 0) {
return IOError(filename_, errno);
}
return Status::OK();
}
bool PosixWritableFile::IsSyncThreadSafe() const { return true; }
uint64_t PosixWritableFile::GetFileSize() { return filesize_; }
Status PosixWritableFile::InvalidateCache(size_t offset, size_t length) {
#ifndef OS_LINUX
return Status::OK();
#else
// free OS pages
int ret = Fadvise(fd_, offset, length, POSIX_FADV_DONTNEED);
if (ret == 0) {
return Status::OK();
}
return IOError(filename_, errno);
#endif
}
#ifdef ROCKSDB_FALLOCATE_PRESENT
Status PosixWritableFile::Allocate(off_t offset, off_t len) {
TEST_KILL_RANDOM("PosixWritableFile::Allocate:0", rocksdb_kill_odds);
IOSTATS_TIMER_GUARD(allocate_nanos);
int alloc_status = 0;
if (allow_fallocate_) {
alloc_status = fallocate(
fd_, fallocate_with_keep_size_ ? FALLOC_FL_KEEP_SIZE : 0, offset, len);
}
if (alloc_status == 0) {
return Status::OK();
} else {
return IOError(filename_, errno);
}
}
Status PosixWritableFile::RangeSync(off_t offset, off_t nbytes) {
if (sync_file_range(fd_, offset, nbytes, SYNC_FILE_RANGE_WRITE) == 0) {
return Status::OK();
} else {
return IOError(filename_, errno);
}
}
size_t PosixWritableFile::GetUniqueId(char* id, size_t max_size) const {
return GetUniqueIdFromFile(fd_, id, max_size);
}
#endif
} // namespace rocksdb
#endif