Detail页面显示shared memory bank conflicts包含两部分:一部分是shared memory之间的bank conflict,另一部分是L1 cache与shared memory之间的bank conflict。 具体到当前的case,padding以后可以保证shared memory bank conflict free,下图Detail页面中的bank conflict是 31457280 - 983040=30474。 L1 cache影响shared memory ...
在做算子优化的时候(比如 GEMM),我们需要充分利用 shared memory 的 broadcast 机制,以及避免 bank conflicts 的出现。同时还会用 LDS.64 或 LDS.128 指令(也可以直接用 float2、float4)等一次访问 8 或 16 …
Shared memory bank conflicts 为了实现并发高访问的高内存带宽,Shared memory 被划分为大小相等的内存模块 bank,以便可以同时访问。因此,可以同时处理跨 b 个不同内存 bank 的任何 n 个地址的 load 和 store,从而产生比单个 bank 带宽高 b 倍的有效带宽。 Note 但是,如果多个线程的请求地址映射到同一个内存 bank...
在优化算子如 GEMM 时，我们充分利用 shared memory 的广播功能，同时避免 bank conflicts。LDS.64 和 LDS.128 指令（比如通过 float2 和 float4）一次可以访问 8 或 16 个字节。然而，官方文档对于超过 4 字节访问的说明并不充分，这导致理解上的困扰。shared memory 的结构是每个 32 个 banks 存...
http://cuda-programming.blogspot.com/2013/02/bank-conflicts-in-shared-memory-in-cuda.html 我这里重点不在bank conflict,而是主要讨论shared memory和 memory bank的对应关系。 文中有这么一段描述: Example Scenario Let’ssay we have an array of size 256 of integer type in global memory and we have...
Well, the memory banks distribute data stored in their bank of shared memory one call at a time. This means that a parallel code can easily be turned into serial code due to bank conflicts (when each thread accesses from the same bank at the same time). There is, however, one exception...
bank = mem/8; So why are these memory banks so important? Well, the memory banks distribute data stored in their bank of shared memory one call at a time. This means that a parallel code can easily be turned into serial code due to bank conflicts (when each thread accesses from the ...
We propose a symbolic execution based framework to systematically uncover shared memory bank conflicts, to propose inputs to realize a given number of shared memory transactions, and to refute the existence of such inputs if the number of shared memory transactions is impossible to achieve during ...
“bank conflictsoccur when multiple threadsin a given warpaccess different address location with in the same bank.” tavivekuh: So when the 16 bit data gets stored in shared memory, a memory bank of width 32 bits will be storing two data variable each of size 16 bits....
Shared Memory Bank Conflicts (l1tex__data_bank_conflicts_{reads,writes}.avg.pct_of_peak_sustained_elapsed) hardware performance counter is showing a value higher than expected. It also counts certain types of stalled cycles. On the Source page: the Memory L1 Transactions Shared and Memory Ideal...