Willy Tarreau 760e81d356 MINOR: backend: implement random-based load balancing ...

For large farms where servers are regularly added or removed, picking
a random server from the pool can ensure faster load transitions than
when using round-robin and less traffic surges on the newly added
servers than when using leastconn.

This commit introduces "balance random". It internally uses a random as
the key to the consistent hashing mechanism, thus all features available
in consistent hashing such as weights and bounded load via hash-balance-
factor are usable. It is extremely convenient because one common concern
when using random is what happens when a server is hammered a bit too
much. Here that can trivially be avoided, like in the configuration below :

    backend bk0
        balance random
        hash-balance-factor 110
        server-template s 1-100 127.0.0.1:8000 check inter 1s

Note that while "balance random" internally relies on a hash algorithm,
it holds the same properties as round-robin and as such is compatible with
reusing an existing server connection with "option prefer-last-server".

2018-05-03 07:20:40 +02:00

..

common

MINOR: h2: detect presence of CONNECT and/or content-length

2018-04-26 10:15:14 +02:00

import

BUILD: threads/plock: fix a build issue on Clang without optimization

2017-11-20 21:06:35 +01:00

proto

MEDIUM: cli: Add payload support

2018-04-26 14:19:33 +02:00

types

MINOR: backend: implement random-based load balancing

2018-05-03 07:20:40 +02:00