Please be aware that this will significantly impact compression ratio. So much actually, that I don't dare use it by default. I'd often use the non-multithreaded mode as for some data (perf.data files with large stack captures, most recently) and reasonable compression speeds of >=50MB/s input multi-threaded modes are not pareto-optimal.

I'll get a small benchmark script for that done over lunch. Come back here later.

> Please be aware that this will significantly impact compression ratio.

Is this a continuation from previous message ? Because multithreading mode of zstd doesn't impact its compression ratio. It's actually an interesting property of zstd : whatever the nb of threads used, the compression ratio remains the same (aka. reproducible).