setdiscovery: limit the size of all sample (issue4411) Further digging on this issue show that the limit on the sample size used in discovery never works for heads. Here is a quote from the code itself: desiredlen = size - len(always) if desiredlen <= 0: # This could be bad if there are very many heads, all unknown to the # server. We're counting on long request support here. The long request support never landed and evolution make the "very many heads, all unknown to the server" case quite common. We implement a simple and stupid hard limit of sample size for all query. This should prevent HTTP 414 error with the current state of the code.