Miles, The weight parameter was added as part of the consistent hash feature added to parent selection with TS-2996. It was never intended for the other round robin strategies.
yes, for round robin = true, a client will always get the same parent until that parent fails and is marked down. When the parent fails, the next available parent would then be selected. On Thu, Nov 3, 2016 at 11:47 AM, Miles Libbey <mlib...@gmail.com> wrote: > On Wed, Nov 2, 2016 at 10:40 AM, John Rushford <jjrushf...@gmail.com> > wrote: > > Miles, > > > > The weight is only used for round_robin = consistent_hash. It is > ignored for all other strategies. > > In the consistent hash strategy, weight defaults to 1 and it’s a > multiplier to the number of replicas of > > A parent inserted alon the hash ring. > > Is there a reason why it was only applied to consistent hash? I think > this is too complex to explain currently. > > > Round_robin=true returns a parent from an array where parent = > client_ip_addr % num_parents. > > I don't understand what that means. Does it effectively pin a parent > to a particular Client IP? > > > Round_robin=strict is just a strict round roubin over the array of > parents. > > > > Thanks > > John Rushford > > jrushf...@apache.org > > > > On 11/2/16, 10:21 AM, "Miles Libbey" <mlib...@apache.org> wrote: > > > > Hey folks- > > > > I'd like to update the parent.config documentation to include the > > weightings feature -- there is an example that shows it, but no text > > that describes it. So, I have some questions :) > > > > - I assume that if someone includes a weight for each parent, the > > round robin=true turns into weighted round robin. I'd guess that ATS > > will sum the weighted values of all the parents, then send each > parent > > (its value)/(sum of weights) of the traffic. True? In the example > > (p1.x.com:8080|1.0; p2.y.com:8080|2.0), would p1 get 1/3 of the > > traffic, and p2 would get the remaining 2/3rds? > > > > - In https://docs.trafficserver.apache.org/en/latest/admin- > guide/files/parent.config.en.html#examples > > , there is an example that has a weighting, even though the selection > > strategy is consistent hash. How does that work? Do the parents just > > get added to the ring that percentage more time? Like in the example, > > p1 gets added to the ring 1 time, and p2 gets added 2 times? > > > > - Does the weighting affect round_robin=strict and latched? > > > > - Is there a max value to the weighting? Anything special about the > > decimal (for instance, is there a limit to the precision?) > > > > Also, what is the difference between round_robin=true and > round_robin=strict? > > > > thanks! > > > > miles > > > > > > > > > -- John Rushford jjrushf...@gmail.com
