aeneasr fc6df51032 Use ristretto to improve find performance ... This patch significantly improves `v.find` performance by using ristretto cache. Ristretto was chosen because it is a very performant, thread-safe cache that does not suffer form congestion or long GC pauses. ``` % go test -bench=. . goos: darwin goarch: amd64 pkg: github.com/spf13/viper BenchmarkGetBool-8 5431267 211 ns/op BenchmarkFind/cache=false-8 289495 4060 ns/op BenchmarkFind/cache=true-8 6980976 171 ns/op BenchmarkGet-8 6332091 193 ns/op BenchmarkGetBoolFromMap-8 235071828 5.09 ns/op PASS ```		2020-09-18 13:22:31 -07:00
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benchmark.json	Use ristretto to improve find performance	2020-09-18 13:22:31 -07:00