get-in* performance

Hashmaps

Version 5's get-in* performs 43‑49% faster than clojure.core/get-in for this hashmap scenario.

(fn [n] (get-in (nested-map n) (path-map n)))

times in seconds, *mean±std*
version	1	2	3	4	5	6
	arg, n
4	1.2e-07±1.0e-09	2.4e-07±1.0e-09	3.7e-07±1.6e-09	4.9e-07±6.4e-09	6.1e-07±1.9e-08	7.0e-07±1.9e-08
5	1.2e-07±1.5e-09	2.4e-07±2.2e-09	3.6e-07±3.4e-09	4.9e-07±7.9e-09	5.8e-07±6.6e-09	7.0e-07±7.3e-09

(fn [n] (get-in* (nested-map n) (path-map n)))

times in seconds, *mean±std*
version	1	2	3	4	5	6
	arg, n
4	1.0e-07±2.0e-09	3.9e-07±1.3e-09	6.1e-07±2.9e-09	7.9e-07±8.0e-09	9.8e-07±7.4e-09	1.1e-06±4.6e-09
5	6.9e-08±1.2e-09	1.4e-07±2.9e-09	2.0e-07±3.3e-09	2.5e-07±3.4e-09	3.0e-07±1.2e-09	3.4e-07±2.0e-09

Lists

Version 5's get-in* with protocol type dispatch performs about 35% faster than version 4 on lists.

(fn [n] (get-in* (nested-list n) (path-list n)))

times in seconds, *mean±std*
version	1	2	3	4
	arg, n
4	2.6e-07±1.7e-09	5.1e-07±2.7e-09	7.6e-07±3.5e-09	1.0e-06±6.0e-09
5	1.7e-07±4.0e-10	3.2e-07±2.4e-09	4.9e-07±8.6e-09	6.6e-07±7.6e-09

Sequences

Version 5 performs about 36% faster for sequences.

(fn [n] (get-in* (nested-seq n) (path-seq n)))

times in seconds, *mean±std*
version	1	2	3	4	5	6
	arg, n
4	2.5e-07±1.7e-09	4.8e-07±8.6e-09	7.2e-07±2.3e-09	9.8e-07±1.4e-08	1.2e-06±1.7e-08	1.5e-06±6.7e-09
5	1.6e-07±8.1e-10	3.0e-07±9.4e-10	4.5e-07±2.0e-09	6.0e-07±4.3e-09	7.8e-07±7.9e-09	9.6e-07±1.0e-08

Vectors

The top two panels are curious: while the clojure.core/get implementation didn't change, the benchmarks run after the library's bump to version 5 showed up to 14% slower performance. One possible interpretation is that the performance improvements demonstrated by get-in* is understated.

Regardless, get-in* performance substantially improved for both patterns of nested vectors, improving by about 70% relative to version 4, and narrowing the performance gap with clojure.core/get-in in the worst case, and bettering it in the best case.

(fn [n] (get-in (narrow-deep-vec n) (path-narrow-deep-vec n)))

times in seconds, *mean±std*
version	1	10	100	1000	10000	100000
	arg, n
4	2.1e-07±4.8e-10	2.9e-07±1.6e-09	3.1e-07±1.1e-09	3.2e-07±2.8e-09	3.4e-07±4.5e-09	3.6e-07±8.4e-09
5	2.2e-07±2.8e-09	3.1e-07±4.5e-09	3.4e-07±2.2e-09	3.6e-07±3.6e-09	3.9e-07±6.1e-09	4.1e-07±4.0e-09

(fn [n] (get-in (nested-vec n) (path-nested-vec n)))

times in seconds, *mean±std*
version	1	2	3	4	5	6
	arg, n
4	1.0e-07±1.9e-09	1.7e-07±5.0e-10	2.4e-07±1.0e-09	3.3e-07±1.8e-09	4.1e-07±8.6e-09	4.9e-07±7.8e-09
5	1.0e-07±3.8e-10	1.8e-07±9.3e-10	2.7e-07±2.6e-09	3.6e-07±5.0e-09	4.4e-07±2.3e-09	5.2e-07±2.2e-09

(fn [n] (get-in* (narrow-deep-vec n) (path-narrow-deep-vec n)))

times in seconds, *mean±std*
version	1	10	100	1000	10000	100000
	arg, n
4	9.2e-07±8.7e-09	1.0e-06±6.7e-09	1.0e-06±8.9e-09	1.1e-06±4.8e-09	1.1e-06±5.9e-09	1.1e-06±5.5e-09
5	3.2e-07±1.1e-09	3.4e-07±1.3e-09	3.6e-07±3.1e-09	4.0e-07±5.3e-09	4.2e-07±4.3e-09	4.4e-07±8.3e-10

(fn [n] (get-in* (nested-vec n) (path-nested-vec n)))

times in seconds, *mean±std*
version	1	2	3	4	5	6
	arg, n
4	1.8e-07±8.6e-10	3.3e-07±1.7e-09	5.0e-07±6.2e-10	6.7e-07±3.5e-09	7.8e-07±3.5e-09	9.8e-07±7.3e-09
5	5.5e-08±9.9e-10	8.7e-08±8.3e-10	1.2e-07±3.1e-10	1.5e-07±2.5e-09	1.8e-07±2.3e-09	2.2e-07±8.2e-10