ConfigFile Format#
A Transfer is defined as a single operation where an Executor reads and adds together values from Source (SRC) memory locations, then writes the sum to destination (DST) memory locations. This simplifies to a simple copy operation when dealing with single SRC/DST.:
SRC 0 DST 0
SRC 1 -> Executor -> DST 1
SRC X DST Y
Three Executors are supported by TransferBench:
Executor: SubExecutor:
1) CPU CPU thread
2) GPU GPU threadblock/Compute Unit (CU)
3) DMA N/A. (May only be used for copies (single SRC/DST)
Each single line in the configuration file defines a set of Transfers (a Test) to run in parallel
There are two ways to specify a Test:
Basic
The basic specification assumes the same number of SubExecutors (SE) used per Transfer A positive number of Transfers is specified followed by that number of triplets describing each Transfer
Transfers SEs (srcMem1->Executor1->dstMem1) … (srcMemL->ExecutorL->dstMemL)
Advanced
A negative number of Transfers is specified, followed by quintuplets describing each Transfer A non-zero number of bytes specified will override any provided value
-Transfers (srcMem1->Executor1->dstMem1 SEs1 Bytes1) … (srcMemL->ExecutorL->dstMemL SEsL BytesL)
Argument Details::
Transfers: Number of Transfers to be run in parallel
SEs : Number of SubExectors to use (CPU threads/ GPU threadblocks)
srcMemL : Source memory locations (Where the data is to be read from)
Executor : Executor is specified by a character indicating type, followed by device index (0-indexed)
- C: CPU-executed (Indexed from 0 to NUMA nodes - 1)
- G: GPU-executed (Indexed from 0 to GPUs - 1)
- D: DMA-executor (Indexed from 0 to GPUs - 1)
dstMemL : Destination memory locations (Where the data is to be written to)
bytesL : Number of bytes to copy (0 means use command-line specified size)
Must be a multiple of 4 and may be suffixed with ('K','M', or 'G')
Memory locations are specified by one or more (device character / device index) pairs
Character indicating memory type followed by device index (0-indexed)
Supported memory locations are:
- C: Pinned host memory (on NUMA node, indexed from 0 to [NUMA nodes-1])
- U: Unpinned host memory (on NUMA node, indexed from 0 to [NUMA nodes-1])
- B: Fine-grain host memory (on NUMA node, indexed from 0 to [NUMA nodes-1])
- G: Global device memory (on GPU device indexed from 0 to [GPUs - 1])
- F: Fine-grain device memory (on GPU device indexed from 0 to [GPUs - 1])
- N: Null memory (index ignored)
Examples::
1 4 (G0->G0->G1) Uses 4 CUs on GPU0 to copy from GPU0 to GPU1
1 4 (C1->G2->G0) Uses 4 CUs on GPU2 to copy from CPU1 to GPU0
2 4 G0->G0->G1 G1->G1->G0 Copes from GPU0 to GPU1, and GPU1 to GPU0, each with 4 SEs
-2 (G0 G0 G1 4 1M) (G1 G1 G0 2 2M) Copies 1Mb from GPU0 to GPU1 with 4 SEs, and 2Mb from GPU1 to GPU0 with 2 SEs
Round brackets and arrows’ ->’ may be included for human clarity, but will be ignored and are unnecessary Lines starting with will be ignored. Lines starting with will be echoed to output
Single GPU-executed Transfer between GPUs 0 and 1 using 4 CUs:
1 4 (G0->G0->G1)
Single DMA executed Transfer between GPUs 0 and 1:
1 1 (G0->D0->G1)
Copy 1Mb from GPU0 to GPU1 with 4 CUs, and 2Mb from GPU1 to GPU0 with 8 CUs:
-2 (G0->G0->G1 4 1M) (G1->G1->G0 8 2M)
“Memset” by GPU 0 to GPU 0 memory:
1 32 (N0->G0->G0)
“Read-only” by CPU 0:
1 4 (C0->C0->N0)
Broadcast from GPU 0 to GPU 0 and GPU 1:
1 16 (G0->G0->G0G1)