The clock to get the current time from.
A function to filter fast / preferred servers.
A function to filter fast / preferred servers. The function takes the calculated average duration of all servers
of a collection, and returns a function for a SolrServer->Duration tuple that returns true/false to indicate if
a server should be considered "fast".
The default value for filterFastServers uses duration <= average * 1.1 + 5
(use 1.1 as multiplier to accept
some deviation, for smaller values like 1 or 2 millis also add some fix value to allow normal deviation).
On start each active server is tested the given number of times to gather initial stats and determine fast/slow servers.
A function that's applied to the predicted response time.
A function that's applied to the predicted response time. This can e.g. be used to quantize the time so that minor differences are ignored.
The delay between tests for slow servers (or all servers if there are no real requests)
The minimum delay between the response of a test and the start of the next test (to limit test frequency)