diff options
Diffstat (limited to 'zen/file_io.cpp')
| -rwxr-xr-x | zen/file_io.cpp | 72 |
1 files changed, 53 insertions, 19 deletions
diff --git a/zen/file_io.cpp b/zen/file_io.cpp index 68b41bcb..bb4848c6 100755 --- a/zen/file_io.cpp +++ b/zen/file_io.cpp @@ -1,6 +1,6 @@ // ***************************************************************************** // * This file is part of the FreeFileSync project. It is distributed under * -// * GNU General Public License: http://www.gnu.org/licenses/gpl-3.0 * +// * GNU General Public License: https://www.gnu.org/licenses/gpl-3.0 * // * Copyright (C) Zenju (zenju AT freefilesync DOT org) - All Rights Reserved * // ***************************************************************************** @@ -115,6 +115,8 @@ size_t FileInput::tryRead(void* buffer, size_t bytesToRead) //throw FileError, E bytesRead = ::read(getHandle(), buffer, bytesToRead); } while (bytesRead < 0 && errno == EINTR); //Compare copy_reg() in copy.c: ftp://ftp.gnu.org/gnu/coreutils/coreutils-8.23.tar.xz + //EINTR is not checked on macOS' copyfile: https://opensource.apple.com/source/copyfile/copyfile-146/copyfile.c.auto.html + //read() on macOS: https://developer.apple.com/legacy/library/documentation/Darwin/Reference/ManPages/man2/read.2.html if (bytesRead < 0) THROW_LAST_FILE_ERROR(replaceCpy(_("Cannot read file %x."), L"%x", fmtPath(getFilePath())), L"read"); @@ -129,23 +131,41 @@ size_t FileInput::tryRead(void* buffer, size_t bytesToRead) //throw FileError, E size_t FileInput::read(void* buffer, size_t bytesToRead) //throw FileError, ErrorFileLocked, X; return "bytesToRead" bytes unless end of stream! { + warn_static("implement PERF_AWESOME_BUFFER program wide for all buffers!?") + + /* + FFS 8.9-9.5 perf issues on macOS: https://www.freefilesync.org/forum/viewtopic.php?t=4808 + app-level buffering is essential to optimize random data sizes; e.g. "export file list": + => big perf improvement on Windows, Linux. No significant improvement on macOS in tests + impact on stream-based file copy: + => no drawback vs block-wise copy loop on Linux, HOWEVER: big perf issue on macOS! + + Possible cause of macOS perf issue unclear: + - getting rid of std::vector::resize() and std::vector::erase() "fixed" the problem + => costly zero-initializing memory? problem with inlining? QOI issue of std:vector on clang/macOS? + - replacing std::copy() with memcpy() also *seems* to have improved speed "somewhat" + */ + const size_t blockSize = getBlockSize(); - assert(memBuf_.size() <= blockSize); + assert(memBuf_.size() >= blockSize); + assert(bufPos_ <= bufPosEnd_ && bufPosEnd_ <= memBuf_.size()); + char* it = static_cast<char*>(buffer); char* const itEnd = it + bytesToRead; for (;;) { - const size_t junkSize = std::min(static_cast<size_t>(itEnd - it), memBuf_.size()); - std::copy (memBuf_.begin(), memBuf_.begin() + junkSize, it); - memBuf_.erase(memBuf_.begin(), memBuf_.begin() + junkSize); - it += junkSize; + const size_t junkSize = std::min(static_cast<size_t>(itEnd - it), bufPosEnd_ - bufPos_); + std::memcpy(it, &memBuf_[bufPos_], junkSize); + bufPos_ += junkSize; + it += junkSize; if (it == itEnd) break; + //-------------------------------------------------------------------- - memBuf_.resize(blockSize); const size_t bytesRead = tryRead(&memBuf_[0], blockSize); //throw FileError, ErrorFileLocked; may return short, only 0 means EOF! => CONTRACT: bytesToRead > 0 - memBuf_.resize(bytesRead); + bufPos_ = 0; + bufPosEnd_ = bytesRead; if (notifyUnbufferedIO_) notifyUnbufferedIO_(bytesRead); //throw X @@ -213,6 +233,7 @@ size_t FileOutput::tryWrite(const void* buffer, size_t bytesToWrite) //throw Fil bytesWritten = ::write(getHandle(), buffer, bytesToWrite); } while (bytesWritten < 0 && errno == EINTR); + //write() on macOS: https://developer.apple.com/legacy/library/documentation/Darwin/Reference/ManPages/man2/write.2.html if (bytesWritten <= 0) { @@ -232,20 +253,32 @@ size_t FileOutput::tryWrite(const void* buffer, size_t bytesToWrite) //throw Fil void FileOutput::write(const void* buffer, size_t bytesToWrite) //throw FileError, X { const size_t blockSize = getBlockSize(); - assert(memBuf_.size() <= blockSize); - const char* it = static_cast<const char*>(buffer); + assert(memBuf_.size() >= blockSize); + assert(bufPos_ <= bufPosEnd_ && bufPosEnd_ <= memBuf_.size()); + + const char* it = static_cast<const char*>(buffer); const char* const itEnd = it + bytesToWrite; for (;;) { - const size_t junkSize = std::min(static_cast<size_t>(itEnd - it), blockSize - memBuf_.size()); - memBuf_.insert(memBuf_.end(), it, it + junkSize); - it += junkSize; + if (memBuf_.size() - bufPos_ < blockSize) //support memBuf_.size() > blockSize to reduce memmove()s, but perf test shows: not really needed! + // || bufPos_ == bufPosEnd_) -> not needed while memBuf_.size() == blockSize + { + std::memmove(&memBuf_[0], &memBuf_[bufPos_], bufPosEnd_ - bufPos_); + bufPosEnd_ -= bufPos_; + bufPos_ = 0; + } + + const size_t junkSize = std::min(static_cast<size_t>(itEnd - it), blockSize - (bufPosEnd_ - bufPos_)); + std::memcpy(&memBuf_[bufPosEnd_], it, junkSize); + bufPosEnd_ += junkSize; + it += junkSize; if (it == itEnd) return; + //-------------------------------------------------------------------- - const size_t bytesWritten = tryWrite(&memBuf_[0], blockSize); //throw FileError; may return short! CONTRACT: bytesToWrite > 0 - memBuf_.erase(memBuf_.begin(), memBuf_.begin() + bytesWritten); + const size_t bytesWritten = tryWrite(&memBuf_[bufPos_], blockSize); //throw FileError; may return short! CONTRACT: bytesToWrite > 0 + bufPos_ += bytesWritten; if (notifyUnbufferedIO_) notifyUnbufferedIO_(bytesWritten); //throw X! } } @@ -253,11 +286,12 @@ void FileOutput::write(const void* buffer, size_t bytesToWrite) //throw FileErro void FileOutput::flushBuffers() //throw FileError, X { - assert(memBuf_.size() <= getBlockSize()); - while (!memBuf_.empty()) + assert(bufPosEnd_ - bufPos_ <= getBlockSize()); + assert(bufPos_ <= bufPosEnd_ && bufPosEnd_ <= memBuf_.size()); + while (bufPos_ != bufPosEnd_) { - const size_t bytesWritten = tryWrite(&memBuf_[0], memBuf_.size()); //throw FileError; may return short! CONTRACT: bytesToWrite > 0 - memBuf_.erase(memBuf_.begin(), memBuf_.begin() + bytesWritten); + const size_t bytesWritten = tryWrite(&memBuf_[bufPos_], bufPosEnd_ - bufPos_); //throw FileError; may return short! CONTRACT: bytesToWrite > 0 + bufPos_ += bytesWritten; if (notifyUnbufferedIO_) notifyUnbufferedIO_(bytesWritten); //throw X! } } |