示例#1
0
        private void AsyncReadPageWithObjectsCallback <TContext>(uint errorCode, uint numBytes, NativeOverlapped *overlap)
        {
            if (errorCode != 0)
            {
                Trace.TraceError("OverlappedStream GetQueuedCompletionStatus error: {0}", errorCode);
            }

            PageAsyncReadResult <TContext> result = (PageAsyncReadResult <TContext>)Overlapped.Unpack(overlap).AsyncResult;

            long ptr = pointers[result.page % BufferSize];

            // Correct for page 0 of HLOG
            if (result.page == 0)
            {
                ptr += Constants.kFirstValidAddress;
            }

            // Check if we are resuming
            if (result.resumeptr > ptr)
            {
                ptr = result.resumeptr;
            }

            // Deserialize all objects until untilptr
            if (ptr < result.untilptr)
            {
                MemoryStream ms = new MemoryStream(result.freeBuffer1.buffer);
                ms.Seek(result.freeBuffer1.offset + result.freeBuffer1.valid_offset, SeekOrigin.Begin);
                pageHandlers.Deserialize(ptr, result.untilptr, ms);
                ms.Dispose();

                ptr = result.untilptr;
                result.freeBuffer1.Return();
                result.freeBuffer1.buffer = null;
                result.resumeptr          = ptr;
            }

            // If we have processed entire page, return
            if (ptr >= pointers[result.page % BufferSize] + PageSize)
            {
                result.Free();

                // Call the "real" page read callback
                result.callback(errorCode, numBytes, overlap);
                return;
            }

            // We will be re-issuing I/O, so free current overlap
            Overlapped.Free(overlap);

            pageHandlers.GetObjectInfo(ref ptr, pointers[result.page % BufferSize] + PageSize, kObjectBlockSize, out long startptr, out long size);
示例#2
0
        private void AsyncReadPageCallback <TContext>(uint errorCode, uint numBytes, NativeOverlapped *overlap)
        {
            if (errorCode != 0)
            {
                Trace.TraceError("OverlappedStream GetQueuedCompletionStatus error: {0}", errorCode);
            }

            PageAsyncReadResult <TContext> result = (PageAsyncReadResult <TContext>)Overlapped.Unpack(overlap).AsyncResult;

            if (Interlocked.Decrement(ref result.count) == 1)
            {
                // We will be issuing another I/O, so free this overlap
                Overlapped.Free(overlap);

                long ptr = (long)pointers[result.page % BufferSize];
                // Correct for page 0 of HLOG
                if (result.page == 0)
                {
                    ptr += Constants.kFirstValidAddress;
                }

                long minObjAddress = long.MaxValue;
                long maxObjAddress = long.MinValue;

                while (ptr < (long)pointers[result.page % BufferSize] + PageSize)
                {
                    if (!Layout.GetInfo(ptr)->Invalid)
                    {
                        if (Key.HasObjectsToSerialize())
                        {
                            Key *key  = Layout.GetKey(ptr);
                            var  addr = ((AddressInfo *)key)->Address;
                            if (addr < minObjAddress)
                            {
                                minObjAddress = addr;
                            }
                            addr += ((AddressInfo *)key)->Size;
                            if (addr > maxObjAddress)
                            {
                                maxObjAddress = addr;
                            }
                        }

                        if (Value.HasObjectsToSerialize())
                        {
                            Value *value = Layout.GetValue(ptr);
                            var    addr  = ((AddressInfo *)value)->Address;
                            if (addr < minObjAddress)
                            {
                                minObjAddress = addr;
                            }
                            addr += ((AddressInfo *)value)->Size;
                            if (addr > maxObjAddress)
                            {
                                maxObjAddress = addr;
                            }
                        }
                    }
                    ptr += Layout.GetPhysicalSize(ptr);
                }

                // Object log fragment should be aligned by construction
                Debug.Assert(minObjAddress % sectorSize == 0);

                var to_read   = (int)(maxObjAddress - minObjAddress);
                var objBuffer = ioBufferPool.Get(to_read);
                result.freeBuffer1 = objBuffer;
                var alignedLength = (to_read + (sectorSize - 1)) & ~(sectorSize - 1);

                // Request objects from objlog
                result.objlogDevice.ReadAsync(
                    (int)(result.page >> (LogSegmentSizeBits - LogPageSizeBits)),
                    (ulong)minObjAddress,
                    (IntPtr)objBuffer.aligned_pointer, (uint)alignedLength, AsyncReadPageCallback <TContext>, result);
            }
            else
            {
                // Load objects from buffer into memory
                long ptr = (long)pointers[result.page % BufferSize];
                // Correct for page 0 of HLOG
                if (result.page == 0)
                {
                    ptr += Constants.kFirstValidAddress;
                }

                MemoryStream ms = new MemoryStream(result.freeBuffer1.buffer);
                ms.Seek(result.freeBuffer1.offset + result.freeBuffer1.valid_offset, SeekOrigin.Begin);

                while (ptr < (long)pointers[result.page % BufferSize] + PageSize)
                {
                    if (!Layout.GetInfo(ptr)->Invalid)
                    {
                        if (Key.HasObjectsToSerialize())
                        {
                            Key.Deserialize(Layout.GetKey(ptr), ms);
                        }

                        if (Value.HasObjectsToSerialize())
                        {
                            Value.Deserialize(Layout.GetValue(ptr), ms);
                        }
                    }
                    ptr += Layout.GetPhysicalSize(ptr);
                }
                ms.Dispose();

                result.Free();

                // Call the "real" page read callback
                result.callback(errorCode, numBytes, overlap);
            }
        }