All tests done on a 2015 Retina MacBook Pro with a SSD.
Ruby 2.2.2
[ruby-2.2.2] ~/Sites/pstore_test ruby test.rb
Calculating -------------------------------------
PStore save 3.794k i/100ms
PStore fetch 3.944k i/100ms
-------------------------------------------------
PStore save 41.438k (± 2.7%) i/s - 208.670k
PStore fetch 40.110k (± 3.7%) i/s - 201.144k
JRuby 1.7.20
[jruby-1.7.20] ~/Sites/pstore_test ruby test.rb
Calculating -------------------------------------
PStore save 3.251k i/100ms
PStore fetch 3.170k i/100ms
-------------------------------------------------
PStore save 35.006k (±12.1%) i/s - 172.303k
PStore fetch 34.401k (±12.1%) i/s - 171.180k
Same, with -Xcompile.invokedynamic=true
Calculating -------------------------------------
PStore save 3.394k i/100ms
PStore fetch 3.437k i/100ms
-------------------------------------------------
PStore save 38.361k (±13.6%) i/s - 190.064k
PStore fetch 38.433k (±12.8%) i/s - 189.035k
JRuby 9000 (b96813f)
[jruby-head] ~/Sites/pstore_test ruby test.rb
Calculating -------------------------------------
PStore save 3.808k i/100ms
PStore fetch 3.944k i/100ms
-------------------------------------------------
PStore save 43.008k (±10.2%) i/s - 213.248k
PStore fetch 42.980k (±10.6%) i/s - 212.976k
Same, with -Xcompile.invokedynamic=true
[jruby-head] ~/Sites/pstore_test <master> ✗ JRUBY_OPTS="-Xcompile.invokedynamic=true" ruby test.rb
Calculating -------------------------------------
PStore save 4.131k i/100ms
PStore fetch 4.162k i/100ms
-------------------------------------------------
PStore save 48.116k (±11.7%) i/s - 239.598k
PStore fetch 49.933k (±12.2%) i/s - 245.558k