hash-balance-factor
Specify the balancing factor for bounded-load consistent hashing
May be used in sections :
defaults frontend listen backend
yes
yes no
no no
no yes
yes
Arguments :
is the control for the maximum number of concurrent requests to
send to a server, expressed as a percentage of the average number
of concurrent requests across all of the active servers.
Specifying a "hash-balance-factor" for a server with "hash-type consistent"
enables an algorithm that prevents any one server from getting too many
requests at once, even if some hash buckets receive many more requests than
others. Setting to 0 (the default) disables the feature. Otherwise,
is a percentage greater than 100. For example, if is 150,
then no server will be allowed to have a load more than 1.5 times the average.
If server weights are used, they will be respected.
If the first-choice server is disqualified, the algorithm will choose another
server based on the request hash, until a server with additional capacity is
found. A higher allows more imbalance between the servers, while a
lower means that more servers will be checked on average, affecting
performance. Reasonable values are from 125 to 200.
See also : "balance" and "hash-type".