microbenchmarking symbol comparison

repl session

user=> (require '[criterium.core :as crit])
nil
user=> (crit/bench (= 'fooooooooo 'fooooooooo))
WARNING: Final GC required 1.201656915742089 % of runtime
Evaluation count : 1916011260 in 60 samples of 31933521 calls.
             Execution time mean : 29.589416 ns
    Execution time std-deviation : 0.164705 ns
   Execution time lower quantile : 29.372524 ns ( 2.5%)
   Execution time upper quantile : 29.952772 ns (97.5%)
                   Overhead used : 1.869223 ns

Found 4 outliers in 60 samples (6.6667 %)
	low-severe	 4 (6.6667 %)
 Variance from outliers : 1.6389 % Variance is slightly inflated by outliers
nil
user=> (crit/bench (= 'fooooooooo 'foooooooooo))
Evaluation count : 1950192600 in 60 samples of 32503210 calls.
             Execution time mean : 29.190524 ns
    Execution time std-deviation : 0.200360 ns
   Execution time lower quantile : 28.900015 ns ( 2.5%)
   Execution time upper quantile : 29.571753 ns (97.5%)
                   Overhead used : 1.869223 ns

Found 1 outliers in 60 samples (1.6667 %)
	low-severe	 1 (1.6667 %)
 Variance from outliers : 1.6389 % Variance is slightly inflated by outliers
nil
user=> (crit/bench (= 'fooooooooo 'gooooooooo))
Evaluation count : 1808873520 in 60 samples of 30147892 calls.
             Execution time mean : 31.436563 ns
    Execution time std-deviation : 0.214456 ns
   Execution time lower quantile : 31.149514 ns ( 2.5%)
   Execution time upper quantile : 31.956988 ns (97.5%)
                   Overhead used : 1.869223 ns

Found 6 outliers in 60 samples (10.0000 %)
	low-severe	 6 (10.0000 %)
 Variance from outliers : 1.6389 % Variance is slightly inflated by outliers
nil
user=>