I was one of the initial developers of Open Library and wrote most of it's backend code. I doubt any of the performance issues could be because of code being sync. Open Library is IO bound and it is most likely spending time waiting for db to respond.
Was there any performance analysis done that indicated that the "code being sync" the main bottleneck?
Was there any performance analysis done that indicated that the "code being sync" the main bottleneck?
Happy to help.