Speed up LinkedHashMap Remove() function from O(n) to O(1) #211

ErenDursun · 2022-08-24T18:49:10Z

This pull request speeds up the LinkedHashMap Remove() function from O(n) to O(1) and closes #178

benchmarks before changes

goos: linux
goarch: amd64
pkg: github.com/emirpasic/gods/maps/linkedhashmap
cpu: AMD Ryzen 7 5800H with Radeon Graphics         
BenchmarkTreeMapGet100-16          	  763164	      1542 ns/op	       0 B/op	       0 allocs/op
BenchmarkTreeMapGet1000-16         	   75256	     15810 ns/op	       0 B/op	       0 allocs/op
BenchmarkTreeMapGet10000-16        	    4922	    239738 ns/op	       0 B/op	       0 allocs/op
BenchmarkTreeMapGet100000-16       	     374	   3386053 ns/op	       0 B/op	       0 allocs/op
BenchmarkTreeMapPut100-16          	  292603	      3995 ns/op	       0 B/op	       0 allocs/op
BenchmarkTreeMapPut1000-16         	   22893	     50650 ns/op	    5952 B/op	     744 allocs/op
BenchmarkTreeMapPut10000-16        	    1977	    607819 ns/op	   77952 B/op	    9744 allocs/op
BenchmarkTreeMapPut100000-16       	     168	   6959023 ns/op	  797964 B/op	   99744 allocs/op
BenchmarkTreeMapRemove100-16       	 1513894	       793.0 ns/op	       0 B/op	       0 allocs/op
BenchmarkTreeMapRemove1000-16      	  146425	      7926 ns/op	      57 B/op	       0 allocs/op
BenchmarkTreeMapRemove10000-16     	    9826	    107367 ns/op	   84967 B/op	       1 allocs/op
BenchmarkTreeMapRemove100000-16    	       1	32919472200 ns/op	80403479216 B/op	  100201 allocs/op
PASS
ok  	github.com/emirpasic/gods/maps/linkedhashmap	51.908s

benchmarks after changes

goos: linux
goarch: amd64
pkg: github.com/emirpasic/gods/maps/linkedhashmap
cpu: AMD Ryzen 7 5800H with Radeon Graphics         
BenchmarkTreeMapGet100-16          	  778264	      1557 ns/op	       0 B/op	       0 allocs/op
BenchmarkTreeMapGet1000-16         	   73291	     15884 ns/op	       0 B/op	       0 allocs/op
BenchmarkTreeMapGet10000-16        	    4999	    242879 ns/op	       0 B/op	       0 allocs/op
BenchmarkTreeMapGet100000-16       	     368	   3280817 ns/op	       0 B/op	       0 allocs/op
BenchmarkTreeMapPut100-16          	  683550	      1707 ns/op	       0 B/op	       0 allocs/op
BenchmarkTreeMapPut1000-16         	   43914	     27164 ns/op	    5952 B/op	     744 allocs/op
BenchmarkTreeMapPut10000-16        	    3007	    398356 ns/op	   77952 B/op	    9744 allocs/op
BenchmarkTreeMapPut100000-16       	     234	   5150464 ns/op	  797956 B/op	   99744 allocs/op
BenchmarkTreeMapRemove100-16       	 1858681	       652.2 ns/op	       0 B/op	       0 allocs/op
BenchmarkTreeMapRemove1000-16      	  187239	      6481 ns/op	       0 B/op	       0 allocs/op
BenchmarkTreeMapRemove10000-16     	   18601	     65581 ns/op	       0 B/op	       0 allocs/op
BenchmarkTreeMapRemove100000-16    	    1670	    653730 ns/op	       0 B/op	       0 allocs/op
PASS
ok  	github.com/emirpasic/gods/maps/linkedhashmap	17.348s