3 ms·
I think they're saying that for the vast majority of code it doesn't matter to optimize as the actual time to run the code is trivial compared to waiting on net
by ender341341 4y ago
I think they're saying that for the vast majority of code it doesn't matter to optimize as the actual time to run the code is trivial compared to waiting on network calls and the like.
- brundolf 4y agoI've never seen any evidence (or even anecdotes, until now) saying this is true. It could be, who knows, but it's a weird thing to assert out of the blue in this kind of conversation, especially when just "doing optimizations [important or not] is a major contributor" is widely-accepted as true and is enough to answer the OP's question
- layer8 4y agoHotspot JIT compilers rely on that. They only compile and optimize code where significant CPU time is spent (hotspots). The majority of code usually remains unJITed.
- brundolf 4y agoI guess the crux is that "important" is relative. JIT compilers (especially hot-spot optimizing ones) are most commonly used for high-level languages like JavaScript, which have a different definition of "important to performance" than eg. systems languages. The OP is talking about compilers that produce binaries, so I think the relevant definition of "important" is that of systems languages, not of the typical JITed language
- layer8 4y agoI was thinking of Java and C#, which are widely deployed for desktop and backend applications, as well as on mobile (Android specifically), and which are quite competitive with C for application performance.
- mike_hearn 4y agoe.g. code that is only ever executed once is a large proportion of many programs (init codepaths etc), but it doesn't make much difference to spend time optimizing it.
- Am4TIfIsER0ppos 4y agoWhat if I don't make any network calls and I also don't want to wait for `div` to complete when `shr` would do?