intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 125 insertions, 0 deletions

diff --git a/library/cpp/logger/sync_page_cache_file.cpp b/library/cpp/logger/sync_page_cache_file.cpp
new file mode 100644
index 0000000000..a0e93a78d7
--- /dev/null
+++ b/library/cpp/logger/sync_page_cache_file.cpp
@@ -0,0 +1,125 @@
+#include "sync_page_cache_file.h"
+#include "record.h"
+
+#include <util/generic/buffer.h>
+#include <util/system/file.h>
+#include <util/system/info.h>
+#include <util/system/mutex.h>
+#include <util/system/rwlock.h>
+#include <util/system/align.h>
+
+class TSyncPageCacheFileLogBackend::TImpl: public TNonCopyable {
+public:
+    TImpl(const TString& path, size_t maxBufferSize, size_t maxPendingCacheSize)
+        : File_{OpenFile(path)}
+        , MaxBufferSize_{maxBufferSize}
+        , MaxPendingCacheSize_{maxPendingCacheSize}
+        , Buffer_{maxBufferSize}
+    {
+        ResetPtrs();
+    }
+
+    ~TImpl() noexcept {
+        try {
+            Write();
+            FlushSync(GuaranteedWrittenPtr_, WrittenPtr_);
+        } catch (...) {
+        }
+    }
+
+    void WriteData(const TLogRecord& rec) {
+        TGuard guard{Lock_};
+
+        Buffer_.Append(rec.Data, rec.Len);
+        if (Buffer_.size() >= MaxBufferSize_) {
+            const i64 prevAlignedEndPtr = PageAlignedWrittenPtr_;
+            Write();
+
+            if (prevAlignedEndPtr < PageAlignedWrittenPtr_) {
+                FlushAsync(prevAlignedEndPtr, PageAlignedWrittenPtr_);
+            }
+
+            const i64 minPendingCacheOffset = PageAlignedWrittenPtr_ - MaxPendingCacheSize_;
+            if (minPendingCacheOffset > GuaranteedWrittenPtr_) {
+                FlushSync(GuaranteedWrittenPtr_, minPendingCacheOffset);
+            }
+        }
+    }
+
+    void ReopenLog() {
+        TGuard guard{Lock_};
+
+        Write();
+        FlushSync(GuaranteedWrittenPtr_, WrittenPtr_);
+
+        File_.LinkTo(OpenFile(File_.GetName()));
+
+        ResetPtrs();
+    }
+
+private:
+    void ResetPtrs() {
+        WrittenPtr_ = File_.GetLength();
+        PageAlignedWrittenPtr_ = AlignDown(WrittenPtr_, GetPageSize());
+        GuaranteedWrittenPtr_ = WrittenPtr_;
+    }
+
+    static TFile OpenFile(const TString& path) {
+        return TFile{path, OpenAlways | WrOnly | ForAppend | Seq | NoReuse};
+    }
+
+    static i64 GetPageSize() {
+        static const i64 pageSize = NSystemInfo::GetPageSize();
+        Y_ASSUME(IsPowerOf2(pageSize));
+        return pageSize;
+    }
+
+    void Write() {
+        File_.Write(Buffer_.Data(), Buffer_.Size());
+        WrittenPtr_ += Buffer_.Size();
+        PageAlignedWrittenPtr_ = AlignDown(WrittenPtr_, GetPageSize());
+        Buffer_.Clear();
+    }
+
+    void FlushAsync(const i64 from, const i64 to) {
+        File_.FlushCache(from, to - from, /* wait = */ false);
+    }
+
+    void FlushSync(const i64 from, const i64 to) {
+        const i64 begin = AlignDown(from, GetPageSize());
+        const i64 end = AlignUp(to, GetPageSize());
+        const i64 length = end - begin;
+
+        File_.FlushCache(begin, length, /* wait = */ true);
+        File_.EvictCache(begin, length);
+
+        GuaranteedWrittenPtr_ = to;
+    }
+
+private:
+    TMutex Lock_;
+    TFile File_;
+
+    const size_t MaxBufferSize_ = 0;
+    const size_t MaxPendingCacheSize_ = 0;
+
+    TBuffer Buffer_;
+    i64 WrittenPtr_ = 0;
+    i64 PageAlignedWrittenPtr_ = 0;
+    i64 GuaranteedWrittenPtr_ = 0;
+};
+
+TSyncPageCacheFileLogBackend::TSyncPageCacheFileLogBackend(const TString& path, size_t maxBufferSize, size_t maxPengingCacheSize)
+    : Impl_(MakeHolder<TImpl>(path, maxBufferSize, maxPengingCacheSize))
+{}
+
+TSyncPageCacheFileLogBackend::~TSyncPageCacheFileLogBackend() {
+}
+
+void TSyncPageCacheFileLogBackend::WriteData(const TLogRecord& rec) {
+    Impl_->WriteData(rec);
+}
+
+void TSyncPageCacheFileLogBackend::ReopenLog() {
+    Impl_->ReopenLog();
+}