On 11 Apr 2018, at 07:11, jhri...@apache.org wrote: > > Author: jhriggs > Date: Wed Apr 11 12:11:05 2018 > New Revision: 1828890 > > URL: http://svn.apache.org/viewvc?rev=1828890&view=rev > Log: > mod_proxy_balancer: Add hot spare member type and corresponding flag (R). Hot > spare members are > used as drop-in replacements for unusable workers in the same load balancer > set. This differs > from hot standbys which are only used when all workers in a set are unusable. > PR 61140.
Speaking of balancer member types, hot spares (new), and hot standbys (existing), is there really a need for hot standbys? When I first started using mod_proxy_balancer many years ago, I actually thought/assumed that "hot standbys" had the behavior that the new spares now have (i.e. drop-in replacements for unavailable workers) until I studied the documentation more carefully. Standbys are really superfluous, since the same behavior can be achieved by sets. For example, the behavior of the following will be exactly the same: <Proxy "balancer://foo"> ProxySet lbmethod=bytraffic BalancerMember "http://server1/"; lbset=0 BalancerMember "http://server2/"; lbset=0 BalancerMember "http://server3/"; lbset=0 status=+H BalancerMember "http://server4/"; lbset=1 BalancerMember "http://server5/"; lbset=1 BalancerMember "http://server6/"; lbset=1 status=+H </Proxy> <Proxy "balancer://foo"> ProxySet lbmethod=bytraffic BalancerMember "http://server1/"; lbset=0 BalancerMember "http://server2/"; lbset=0 BalancerMember "http://server3/"; lbset=1 BalancerMember "http://server4/"; lbset=2 BalancerMember "http://server5/"; lbset=2 BalancerMember "http://server6/"; lbset=3 </Proxy> So, is there really any reason to keep hot standbys? Do we consider the concept of the +H flag to be easier to understand or use than LB sets? If so, do we just need better docs? Am I missing any nuances of the H flag? I would love to see standbys go away, personally. - Jim
