On 12/01/17 13:53, Pierre Ossman wrote:
> For small updates I see performance growing logarithmically, measured in
> pixels/second. At around 500k pixels it starts leveling off at ~1.5
> Gpixels/second. After that the performance starts dropping linearly as
> the update grows.
I'll answer myself here...
This seems to be a CPU cache issue. Below this limit I see:
4,469,985 cache-misses:u # 0.336 % of all cache
35,279,259,258 instructions:u # 1.70 insn per cycle
Above the limit I get:
194,571,782 cache-misses:u # 30.322 % of all cache
18,084,891,734 instructions:u # 0.73 insn per cycle
So no wonder things take a turn for the worse.
I'll have to think a bit on how to make this more efficient. Ideas are always
Pierre Ossman Software Development
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A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
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