Smalltalk and tiered compile data

[Mark Roos]

So I ran some tests using a simple benchmark using the jdk8-b23 from the 
Openjdk google code.

Without tiered compile I get:  ( times in nanoseconds )
52101000
53973000
20932000

with tiered on
493788000
521448000
513287000
342930000
15048000

But if I invalidate all call sites before the benchmark with tiered I see:

449127000
288584000
80717000
36255000

and without tiered
49210000
744625000
27179000
26377000
24514000

in all cases more runs after show no changes for 30 runs.

So tiered starts very very very  slow but ends better.  Both seem to have 
a hard time if call sites have their
targets reset.

any thoughts on how I might get the best always? Especially for callsite 
resets.
 And why would the startup be 10x slower for tiered?

By the way the data for jdk7u4 is similar but its best times are slower.

regards
mark
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