[Python-Dev] Opcode cache in ceval loop

[Matthias Bussonnier]

> On Feb 3, 2016, at 13:22, Yury Selivanov <yselivanov.ml at gmail.com> wrote:
> 
> 
> An ideal way would be to calculate a hit/miss ratio over time
> for each cached opcode, but that would be an expensive
> calculation.

Do you mean like a sliding windows ?
Otherwise if you just want a let's say 20% miss threshold, you increment by 1 on hit, 
and decrement by 4 on miss. 


On Feb 3, 2016, at 13:37, Sven R. Kunze <srkunze at mail.de> wrote:

> On 03.02.2016 22:22, Yury Selivanov wrote:
>> One way of tackling this is to give each optimized opcode
>> a counter for hit/misses.  When we have a "hit" we increment
>> that counter, when it's a miss, we decrement it.
> 
> Within a given range, I suppose. Like:
> 
> c = min(c+1, 100)


Min might be overkill, maybe you can use a or mask, to limit the windows range
to 256 consecutive call ? 
-- 
M





> 
> Yury
> 
> _______________________________________________
> Python-Dev mailing list
> Python-Dev at python.org
> https://mail.python.org/mailman/listinfo/python-dev
> Unsubscribe: https://mail.python.org/mailman/options/python-dev/bussonniermatthias%40gmail.com