N allocs -> 1 alloc -> bit faster still
N allocs -> 1 alloc -> bit faster still

taskset --cpu-list 5 go test -bench Benchmark . -benchmem
goos: linux
goarch: amd64
pkg: github.com/grafana/metrictank/mdata/cache
BenchmarkAddAsc         	 1000000	      1053 ns/op	     145 B/op	       3 allocs/op
BenchmarkAddDesc1       	   10000	   1456538 ns/op	   21720 B/op	       7 allocs/op
BenchmarkAddDesc4       	   10000	   1452870 ns/op	   21729 B/op	       9 allocs/op
BenchmarkAddDesc64      	    9984	   1449829 ns/op	   21700 B/op	       9 allocs/op
BenchmarkAddRangeAsc    	 3000000	       366 ns/op	     117 B/op	       0 allocs/op
BenchmarkAddRangeDesc4  	   10000	    363554 ns/op	    5503 B/op	       1 allocs/op
BenchmarkAddRangeDesc64 	   99968	    277954 ns/op	    3276 B/op	       0 allocs/op
PASS
ok  	github.com/grafana/metrictank/mdata/cache	84.321s

benchcmp post2.txt post3.txt
benchmark                   old ns/op     new ns/op     delta
BenchmarkAddAsc             1229          1053          -14.32%
BenchmarkAddDesc1           1454771       1456538       +0.12%
BenchmarkAddDesc4           1459969       1452870       -0.49%
BenchmarkAddDesc64          1453576       1449829       -0.26%
BenchmarkAddRangeAsc        945           366           -61.27%
BenchmarkAddRangeDesc4      363506        363554        +0.01%
BenchmarkAddRangeDesc64     278120        277954        -0.06%

benchmark                   old allocs     new allocs     delta
BenchmarkAddAsc             3              3              +0.00%
BenchmarkAddDesc1           7              7              +0.00%
BenchmarkAddDesc4           9              9              +0.00%
BenchmarkAddDesc64          9              9              +0.00%
BenchmarkAddRangeAsc        1              0              -100.00%
BenchmarkAddRangeDesc4      2              1              -50.00%
BenchmarkAddRangeDesc64     1              0              -100.00%

benchmark                   old bytes     new bytes     delta
BenchmarkAddAsc             145           145           +0.00%
BenchmarkAddDesc1           21720         21720         +0.00%
BenchmarkAddDesc4           21729         21729         +0.00%
BenchmarkAddDesc64          21700         21700         +0.00%
BenchmarkAddRangeAsc        137           117           -14.60%
BenchmarkAddRangeDesc4      5502          5503          +0.02%
BenchmarkAddRangeDesc64     3276          3276          +0.00%

raintank/metrictank,replay/metrictank,replay/metrictank,raintank/raintank-metric,raintank/metrictank,raintank/metrictank,replay/metrictank,raintank/metrictank,raintank/raintank-metric,replay/metrictank,raintank/raintank-metric