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One thing that bugs me about the "140% improvement" PR is that even the author only has some hand-wavy theory as to why that change from local variables to an o
by idbehold 3y ago
One thing that bugs me about the "140% improvement" PR is that even the author only has some hand-wavy theory as to why that change from local variables to an object with those two properties made such a drastic improvement. V8 performance (well, let's be honest, any JS runtime's performance) is just a bunch of guess and check work.
- xwowsersx 3y agoIt's definitely unsettling when we don't fully understand why a fix works. I suppose one could argue that, in that sense, software development is as much art as it is science... you learn and adapt, and over time, the understanding of why certain fixes work may become clearer. I wish I could remember the specific instances of this throughout my career, but I remember at least a few where we were happy to have the fix (even though it was annoying we didn't understand the why) and then months or more later we came to fully understand why. I distinctly remember how, in many of these cases, it felt to us like it would've impossible to even come close to the why without first just having the fix. That's what made it even more frustrating — that we felt we needed to understand the underlying issue in order to fix it but then it felt like there's no way we would've understood what the underlying issue was without the fix! In that way, it kind of all just felt like luck or a miracle...which is definitely not very confidence-inspiring.