First, here is no data or evidence to suggest this is the case, so not sure why you are trying to make up excuses for them?
Second, zstd is fully deterministic in multithreaded cases.
It does not matter what threading you select, it will output byte for byte identical results.
I believe all of their compressors are similarly deterministic regardless of number of threads, but i admit i have not checked every one of them under all conditions.
If they had questions, they could have, you know, asked, and would have gotten the same answer.
But that just goes back to what i said - it does not appear this change was particularly well thought out.
Second, zstd is fully deterministic in multithreaded cases. It does not matter what threading you select, it will output byte for byte identical results.
See a direct answer to this question here: https://github.com/facebook/zstd/issues/2079
I believe all of their compressors are similarly deterministic regardless of number of threads, but i admit i have not checked every one of them under all conditions.
If they had questions, they could have, you know, asked, and would have gotten the same answer.
But that just goes back to what i said - it does not appear this change was particularly well thought out.