The saw shaped bottlenecks are easy to reproduce. Basically if I set the upload speed to let say 100kb and have download set to unlimited. Soon as current upload speeds reach 100kbs boom download and upload speeds all drop to 0. If both upload and download are unlimited, no issue. This only seems to be a issue with the upload being maxed out(for me at least). As a work around I've basically had to block peers I do not want to send to, as that it affects download speeds. Personally I feel upload limits should not affect download speeds. Also note I'm running 1.4.103