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[TransferBench] Changing default per block multiple to 256B, adding BLOCK_BYTES env var (#446)

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gilbertlee-amd
2021-10-25 11:23:29 -06:00
committed by GitHub
parent 31f9e79775
commit 18246fc191
2 changed files with 20 additions and 9 deletions
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tools/TransferBench/EnvVars.hpp
+10 -1
View File
@@ -28,6 +28,7 @@ public:
int samplingFactor; // Affects how many different values of N are generated (when N set to 0)
int numCpuPerLink; // Number of CPU child threads to use per CPU link
int sharedMemBytes; // Amount of shared memory to use per threadblock
int blockBytes; // Each CU, except the last, gets a multiple of this many bytes to copy
std::vector<float> fillPattern; // Pattern of floats used to fill source data
@@ -51,6 +52,7 @@ public:
samplingFactor = GetEnvVar("SAMPLING_FACTOR" , DEFAULT_SAMPLING_FACTOR);
numCpuPerLink = GetEnvVar("NUM_CPU_PER_LINK" , DEFAULT_NUM_CPU_PER_LINK);
sharedMemBytes = GetEnvVar("SHARED_MEM_BYTES" , maxSharedMemBytes / 2 + 1);
blockBytes = GetEnvVar("BLOCK_BYTES" , 256);
// Check for fill pattern
char* pattern = getenv("FILL_PATTERN");
@@ -141,6 +143,11 @@ public:
printf("[ERROR] SHARED_MEM_BYTES must be between 0 and %d\n", maxSharedMemBytes);
exit(1);
}
if (blockBytes <= 0 || blockBytes % 4)
{
printf("[ERROR] BLOCK_BYTES must be a positive multiple of 4\n");
exit(1);
}
}
// Display info on the env vars that can be used
@@ -162,6 +169,7 @@ public:
printf(" NUM_CPU_PER_LINK=C - Use C threads per Link for CPU-executed copies\n");
printf(" FILL_PATTERN=STR - Fill input buffer with pattern specified in hex digits (0-9,a-f,A-F). Must be even number of digits, (byte-level big-endian)\n");
printf(" SHARED_MEM_BYTES=X - Use X shared mem bytes per threadblock, potentially to avoid multiple threadblocks per CU\n");
printf(" BLOCK_BYTES=B - Each CU (except the last) receives a multiple of BLOCK_BYTES to copy\n");
}
// Display env var settings
@@ -206,7 +214,8 @@ public:
}
printf("\n");
printf("%-20s = %12s : Using %d shared mem per threadblock\n", "SHARED_MEM_BYTES",
getenv("SHARED_MEM_BYTES") ? "(specified)" : "(unspecified)", sharedMemBytes);
getenv("SHARED_MEM_BYTES") ? "(specified)" : "(unset)", sharedMemBytes);
printf("%-20s = %12d : Each CU gets a multiple of %d bytes to copy\n", "BLOCK_BYTES", blockBytes, blockBytes);
printf("\n");
}
};
tools/TransferBench/TransferBench.cpp
+10 -8
View File
@@ -202,21 +202,23 @@ int main(int argc, char **argv)
// Initialize source memory with patterned data
CheckOrFill(MODE_FILL, N, ev.useMemset, ev.useHipCall, ev.fillPattern, links[i].srcMem + initOffset);
// Each block needs to know src/dst pointers and how many elements to transfer
// Figure out the sub-array each block does for this Link
// - Partition N as evenly as posible, but try to keep blocks as multiples of 32,
// - Partition N as evenly as posible, but try to keep blocks as multiples of BLOCK_BYTES bytes,
// except the very last one, for alignment reasons
int targetMultiple = ev.blockBytes / sizeof(float);
if (links[i].exeMemType == MEM_GPU)
{
size_t assigned = 0;
int maxNumBlocksToUse = std::min((N + 31) / 32, (size_t)links[i].numBlocksToUse);
int maxNumBlocksToUse = std::min((N + targetMultiple - 1) / targetMultiple, (size_t)links[i].numBlocksToUse);
for (int j = 0; j < links[i].numBlocksToUse; j++)
{
BlockParam param;
int blocksLeft = std::max(0, maxNumBlocksToUse - j);
size_t leftover = N - assigned;
size_t roundedN = (leftover + 31) / 32;
param.N = blocksLeft ? std::min(leftover, ((roundedN / blocksLeft) * 32)) : 0;
size_t roundedN = (leftover + targetMultiple - 1) / targetMultiple;
param.N = blocksLeft ? std::min(leftover, ((roundedN / blocksLeft) * targetMultiple)) : 0;
param.src = links[i].srcMem + assigned + initOffset;
param.dst = links[i].dstMem + assigned + initOffset;
assigned += param.N;
@@ -228,13 +230,13 @@ int main(int argc, char **argv)
{
// For CPU-based copy, divded based on the number of child threads
size_t assigned = 0;
int maxNumBlocksToUse = std::min((N + 31) / 32, (size_t)ev.numCpuPerLink);
int maxNumBlocksToUse = std::min((N + targetMultiple - 1) / targetMultiple, (size_t)ev.numCpuPerLink);
for (int j = 0; j < ev.numCpuPerLink; j++)
{
int blocksLeft = std::max(0, maxNumBlocksToUse - j);
size_t leftover = N - assigned;
size_t roundedN = (leftover + 31) / 32;
links[i].blockParam[j].N = blocksLeft ? std::min(leftover, ((roundedN / blocksLeft) * 32)) : 0;
size_t roundedN = (leftover + targetMultiple - 1) / targetMultiple;
links[i].blockParam[j].N = blocksLeft ? std::min(leftover, ((roundedN / blocksLeft) * targetMultiple)) : 0;
links[i].blockParam[j].src = links[i].srcMem + assigned + initOffset;
links[i].blockParam[j].dst = links[i].dstMem + assigned + initOffset;
assigned += links[i].blockParam[j].N;
@@ -1158,7 +1160,7 @@ double GetPeakBandwidth(EnvVars const& ev, size_t N, int isBidirectional,
// Skip bidirectional on same device
if (isBidirectional && srcMemType == dstMemType && srcIndex == dstIndex) return 0.0f;
// Prepare Links
links[0].srcMemType = links[0].exeMemType = links[1].dstMemType = srcMemType;
links[0].srcIndex = links[0].exeIndex = links[1].dstIndex = srcIndex;