`NCCL_TESTS_SPLIT` serves as new way of computing the color for splitting communicators.
Will be overrided by `NCCL_TESTS_SPLIT_MASK`.
Examples:
NCCL_TESTS_SPLIT_MASK="0x7" # color = rank & 0x7. What we do today to run on a DGX with one GPU per node.
NCCL_TESTS_SPLIT="AND 0x7" # color = rank & 0x7. New way to run on one GPU per node on a DGX, equivalent to NCCL_TESTS_SPLIT_MASK=0x7
NCCL_TESTS_SPLIT="MOD 72" # color = rank % 72. One GPU per NVLink domain on an NVL72 system.
NCCL_TESTS_SPLIT="DIV 72" # color = rank / 72. Intra NVLink domain on NVL72.
You can also use: "%" "&" "|" "/" for short.
Extra spaces in the middle will be automatically ignored.
Not case sensitive.
The followings are all equivalent:
NCCL_TESTS_SPLIT="%0x7"
NCCL_TESTS_SPLIT="%0b111"
NCCL_TESTS_SPLIT="AND 7"
NCCL_TESTS_SPLIT="and 0x7"
[ROCm/rccl-tests commit: a89cf07fe8]
* Added "verifiable", a suite of kernels for generating and verifying reduction
input and output arrays in a bit-precise way.
* Data corruption errors now reported in number of wrong elements instead of max
deviation.
* Use ncclGetLastError.
* Don't run hypercube on non-powers of 2 ranks.
* Fix to hypercube data verification.
* Use "thread local" as the defaut CUDA capture mode.
* Replaced pthread_yield -> sched_yield()
* Bugfix to the cpu-side barrier/allreduce implementations.
[ROCm/rccl-tests commit: 51af5572bf]
Add error checking for minbytes and maxbytes arguments
Also accept lowercase literals when parsing size arguments and print errors and usage on stderr.
[ROCm/rccl-tests commit: c4de829d91]
Major rework to merge most of the changes from the NCCL internal
tests into the public ones
Added "-m <agg_iters>" operation aggregation option.
Data integrity checking is now much more performant at scale.
Startup times at scale are improved.
Test latency units are now displayed in usec.
[ROCm/rccl-tests commit: cbe7f65400]
David Addison
Junyu Ma
John Bachan
David Addison
Stefano Salsano
Kaiming Ouyang
Giuseppe Congiu
Sylvain Jeaugey
Greg Inozemtsev
Luke Yeager