Tweaking.

This commit is contained in:
Daniel Lemire 2020-06-17 13:27:17 -04:00
parent 16f41ea059
commit 14ceacac73
1 changed files with 3 additions and 1 deletions

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@ -160,6 +160,8 @@ Recent versions of Microsoft Visual Studio on Windows provides support for the L
Downclocking Downclocking
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You should not expect the simdjson library to cause downclocking of your recent Intel CPU cores.
On some Intel processors, using SIMD instructions in a sustained manner on the same CPU core may result in a phenomenon called downclocking whereas the processor initially runs these instructions at a slow speed before reducing the frequency of the core for a short time (milliseconds). Intel refers to these states as licenses. On some current Intel processors, it occurs under two scenarios: On some Intel processors, using SIMD instructions in a sustained manner on the same CPU core may result in a phenomenon called downclocking whereas the processor initially runs these instructions at a slow speed before reducing the frequency of the core for a short time (milliseconds). Intel refers to these states as licenses. On some current Intel processors, it occurs under two scenarios:
- [Whenever 512-bit AVX-512 instructions are used](https://lemire.me/blog/2018/09/07/avx-512-when-and-how-to-use-these-new-instructions/). - [Whenever 512-bit AVX-512 instructions are used](https://lemire.me/blog/2018/09/07/avx-512-when-and-how-to-use-these-new-instructions/).