Hi Levente,


> +       lowerLimit <= 7 ifTrue: [
> +               lowerLimit <= 3 ifTrue: [ ^3 ].
> +               lowerLimit <= 5 ifTrue: [ ^5 ].
> +               ^7 ].


That's better, but it still has that same fundamental problem.  Every time
a developer makes a HashedCollection of a known-at-runtime size (e.g., in a
variable), they're forced to choose between execution performance pain or
code pain.

    {
   '[ Dictionary new ]'->'100% of baseline rate, 27,600,000 per second.
36.2 nanoseconds per run. 11.33547 % GC time.'

    "performance pain?"
    '[ Dictionary new: 1 ]'->'60% of baseline rate, 16,600,000 per second.
60.1 nanoseconds per run. 5.61888 % GC time.'
    '[ Dictionary new: 2 ]'->'61% of baseline rate, 16,900,000 per second.
59.2 nanoseconds per run. 5.67886 % GC time.'
    '[ Dictionary new: 3 ]'->'59% of baseline rate, 16,300,000 per second.
61.5 nanoseconds per run. 6.77864 % GC time.'

    "into #sizeFor:"
    '[ Dictionary new: 4 ]'->'57% of baseline rate, 15,800,000 per second.
63.5 nanoseconds per run. 7.87685 % GC time.'

    "or code pain?"
    '[ sz > 3
            ifTrue: [ Dictionary new: sz ]
            ifFalse: [ Dictionary new ] ]'->'97% of baseline rate,
26,900,000 per second. 37.2 nanoseconds per run. 11.09778 % GC time.'}

For the most part, they won't even know about this anomaly (and shouldn't
have to).  No one assumes such a heavy penalty for #new: over #new when the
size is <= the default size.

I like every other aspect of your improvements here!  But may we go with
the Collections-cmm.873 variation please?  It fixes that issue, check it
out!

    {'[ Dictionary new ]'->'100% of baseline rate, 29,100,000 per second.
34.4 nanoseconds per run. 5.9988 % GC time.'
    '[ Dictionary new: 1 ]'->'103% of baseline rate, 29,900,000 per second.
33.4 nanoseconds per run. 4.9 % GC time.'
    '[ Dictionary new: 2 ]'->'103% of baseline rate, 30,100,000 per second.
33.2 nanoseconds per run. 4.88 % GC time.'
    '[ Dictionary new: 3 ]'->'95% of baseline rate, 27,600,000 per second.
36.3 nanoseconds per run. 5.62 % GC time.'

Best,
  Chris




>
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