Duplicate RNG state across block to avoid need for synchronization #879
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maleadt
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Compared to the timings in #788 (comment), about a 4% slowdown. |
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@@ Coverage Diff @@
## master #879 +/- ##
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- Coverage 77.14% 77.13% -0.01%
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Files 121 121
Lines 7546 7544 -2
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- Hits 5821 5819 -2
Misses 1725 1725
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Instead of 128 bytes, the device RNG now uses 32 times as much state, or 4KB out of 64KB in total. So that might lower occupancy, but on the flip side, it allows generating numbers without synchronization, and thus without the need to call
rand()in a uniform manner. That turned out to be a fairly annoying requirement.In the future, we can switch to a different RNG that uses less state (like counter-based ones), but for now this seems like a good stopgap measure.