Olivier Houchard 9fe72bba3c MAJOR: leastconn; Revamp the way servers are ordered. ... For leastconn, servers used to just be stored in an ebtree. Each server would be one node. Change that so that nodes contain multiple mt_lists. Each list will contain servers that share the same key (typically meaning they have the same number of connections). Using mt_lists means that as long as tree elements already exist, moving a server from one tree element to another does no longer require the lbprm write lock. We use multiple mt_lists to reduce the contention when moving a server from one tree element to another. A list in the new element will be chosen randomly. We no longer remove a tree element as soon as they no longer contain any server. Instead, we keep a list of all elements, and when we need a new element, we look at that list only if it contains a number of elements already, otherwise we'll allocate a new one. Keeping nodes in the tree ensures that we very rarely have to take the lbrpm write lock (as it only happens when we're moving the server to a position for which no element is currently in the tree). The number of mt_lists used is defined as FWLC_NB_LISTS. The number of tree elements we want to keep is defined as FWLC_MIN_FREE_ENTRIES, both in defaults.h. The value used were picked afrer experimentation, and seems to be the best choice of performances vs memory usage. Doing that gives a good boost in performances when a lot of servers are used. With a configuration using 500 servers, before that patch, about 830000 requests per second could be processed, with that patch, about 1550000 requests per second are processed, on an 64-cores AMD, using 1200 concurrent connections.		2025-04-01 18:05:30 +02:00
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haproxy	MAJOR: leastconn; Revamp the way servers are ordered.	2025-04-01 18:05:30 +02:00
import	MINOR: mt_list: Implement mt_list_try_lock_prev().	2025-04-01 18:05:30 +02:00
make	BUILD: makefile: add a qinfo macro to pass info in quiet mode	2025-01-08 11:26:05 +01:00