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by lpgauth 2183 days ago
mixing simd and non-simd load is not recommended.

https://blog.cloudflare.com/on-the-dangers-of-intels-frequen...

1 comments

this is well-addressed here: https://github.com/simdjson/simdjson/blob/master/doc/perform... .

first off, AVX2 is a subset of SIMD instructions - SIMDjson includes a large number of implementations including several which do not use AVX2 at all.

next, only a subset of AVX2 instructions cause downclocking (namely, the 512 bit wide ones), which SIMDjson does not use. throwing out the use of "SIMD" entirely because you read an article about a specific AVX512 instruction which caused down-clocking might be a bit premature, no?