On Tue, Mar 31, 2026 at 6:30 PM Nathan Bossart <[email protected]> wrote:
> On Fri, Mar 27, 2026 at 07:48:38PM +0100, KAZAR Ayoub wrote: > > I added a prescan loop inside the simd helpers trying to catch special > > chars in sizeof(Vector8) characters, i measured how good is this at > > reducing the overhead of starting simd and exiting at first vector: > > the scalar loop is better than SIMD for one vector if it finds a special > > character before 6th character, worst case is not a clean vector, where > the > > scalar loop needs 20 more cycles compared to SIMD. > > This helps mitigate the case of JSON(B) in CSV format, this is why I only > > added this for CSV case only. > > Interesting. > > > In a benchmark with 10M early SIMD exit like the JSONB case, the previous > > 3% regression is gone. > > While these are nice results, I think it's best that we target v20 for this > patch so that we have more time to benchmark and explore edge cases. > Thanks for the review. Fair enough, I'll try many more cases in the upcoming weeks to make sure we're not missing anything. > > -- > nathan Regards, Ayoub
