Re: [RFC] JIT

On Thu, Jan 31, 2019 at 6:47 PM Kalle Sommer Nielsen <kalle@php.net> wrote: > Without my usual Windows bias, I do believe it is a considerable fact > like Nikita pointed out as Windows is a first class citizen in terms > of operating systems we support. While PHP on Windows may not have the > speed that the Unix counterpart have, it is still a very important > development platform. Many developers develop on Windows and deploy on > a Unix based system, being unable to test such an important feature in > a development environment is also a large question mark. > As long as we can agree that very few actually *deploy *on Windows, I think we're on solid grounds. As the JIT implementation is likely to have at least *some* significant differences compared to Linux, I'm not sure what testing it on Windows would give you. JIT is supposed to be entirely transparent, and the performance characteristics - as well as the bug patterns - are likely to be quite different on Linux vs. Windows, at least in many cases. Is it really that important to have? I'm honestly a bit perplexed by how many people here viewing Windows support as a must have, while at the same time I think we all agree PHP is very scarcely found on production Windows servers, and JIT is a predominantly production feature. I'm personally interested in taking a look at it (and I'm certain > Anatol does too), but simply dismissing is a no-go for me. It'd be interesting to evaluate the cost associated with supporting Windows. Bare in mind, we're proposing to vote on this as a production feature for PHP 8 - which realistically means almost two years from now *at the earliest*. I'm sure we'd have Windows support a lot sooner than that if we decide that it's a must have. I agree with Nikita that the key question is in fact, do we or do we not want to introduce JIT in - with the main question being the maintenance cost. Let's tackle this question first, otherwise - why send Dmitry (and maybe others) for doing more work (Windows support) if we are likely to flush it all down the toilet? I think that if we reach the conclusion that Windows support is a must, we can condition the inclusion of JIT based on having it. Let's first agree on whether we want it in the first place. Zeev