On 12-10-2022 22:20, Damien Mattei wrote: > Mutex? i do not think code has situation where dead lock could happen, > it is a code about minimalising logic expressions, it uses minterms , > minterms set is a set of minterms :like this: I didn't mean deadlocks, I just meant a single mutex being taken by all the threads. Also, you seem to have a global hash table on line 1603 -- presumably there's a mutex in there (and even if not, likely there are CPU cache issues). > [...] I propose to minimise this complicated test case (doesn't need to be equivalent, just needs to demonstrate the 'map-par slower than map') and to change it to standard-ish Scheme instead of your Scheme+ variant. > On Wed, Oct 12, 2022 at 8:45 PM Maxime Devos > wrote: > > [rest of copied previous message, without any comments] This is top-posting. For why not to top-post, https://wiki.lyx.org/FAQ/ListNetiquette has various information. Greetings, Maxime.