static Buffer ReadBuffer_common(SMgrRelation smgr, char relpersistence, ForkNumber forkNum, BlockNumber blockNum, ReadBufferMode mode, BufferAccessStrategy strategy, bool *hit) { ... isExtend = (blockNum == P_NEW); ... if (isExtend) // 拿一个新的页面,比如0、1已经使用,当前有两个页面,...
latch_mode 是 BTR_MODIFY_PREV 或 BTR_MODIFY_TREE 0xFFFF 是最大的 entry counter(IBUF_REC_OFFSET_COUNTER 域为两个字节),所以 cursor 会定位到对应于同一二级索引页的具有最大 counter 的 entry,记为 max_counter。max_counter+1 即为待插入 entry 的 counter 但在每一次 ibuf merge ,清空了该二级索引...
The waiting is performed by a call to log_write_up_to(end_lsn - log.buf_size), which has a loop with short sleeps. We assume that it is unlikely that the waiting is actually needed. TheMONITOR_LOG_ON_BUFFER_SPACE* counters track number of iterations spent in the waiting loop. If th...
如果 BufMappingLock 是单个系统范围(system-wide)的锁,则两个进程都应等待另一个进程的处理,具体取决于哪个进程先开始处理。 Fig. 8.7. Two processes simultaneously acquire the respective partitions of BufMappingLock in exclusive mode to insert new data entries. 缓冲表需要许多其他锁。例如,缓冲区表在内部...
mSlots[slot].mFrameNumber = currentFrameNumber; //给BufferItem赋值 item.mGraphicBuffer = mSlots[slot].mGraphicBuffer; item.mSlot = slot; output->bufferReplaced = false; if (mCore->mQueue.empty()) { //如果mQueue为空,就直接把BufferItem push到mQueue尾部。
staticulintibuf_get_volume_buffered(...lint*n_recs,/*!< in/out: minimum number of records on the page after the buffered changes have been applied, or NULL to disable the counting */) 计算方式就是遇到 IBUF_OP_DELETE 就把 n_recs --,遇到 IBUF_OP_INSERT或 IBUF_OP_DELETE_MARK 要注意...
Please note: This article contains a number of animations. Click on the button below an image to activate its animation.Immediate mode rasterizersThe traditional interface presented by a graphics API is that of submitting triangles in order, with the concept that the GPU renders each triangle in...
size{Number} Allocates a newnon-zero-filledand non-pooledBufferofsizebytes. Thesizemust be less than or equal to the value ofrequire('buffer').kMaxLength(on 64-bit architectures,kMaxLengthis(2^31)-1). Otherwise, a [RangeError][] is thrown. A zero-length Buffer will be created if a...
Creates a new buffer pointer over the specified number of contiguous instances beginning at the given pointer. Instance Properties varbaseAddress:UnsafeMutablePointer<Element>? A pointer to the first element of the buffer. letcount:Int The number of elements in the buffer. ...
{ HANDLE hDevice; HANDLE hAllocation; UINT SegmentId; SIZE_T OffsetInPages; SIZE_T NumberOfPages; DXGK_ADL Adl; DXGK_MAPAPERTUREFLAGS Flags; ULONG AdlOffset; PVOID CpuVisibleAddress; } MapApertureSegment2; DXGK_BUILDPAGINGBUFFER_NOTIFY_FENCE_RESIDENCY NotifyFenceResidency; DXGK_BUILDP...