On Thu, Dec 17, 2020 at 5:30 PM Aaron Piotrowski <aa...@trowski.com> wrote:
> Hello everyone! > > I would like to introduce an RFC for adding full-stack fibers to PHP: > https://wiki.php.net/rfc/fibers > > Fibers are primarily used to implement green-threads or coroutines for > asynchronous I/O. Fibers are similar to threads, except fibers exist within > a single thread and require cooperative scheduling of the fibers by the > process. Since fibers do not require a full CPU context switch, they are > lightweight and more performant than multi-processing or threading for > awaiting I/O. > > An implementation as an extension is at https://github.com/amphp/ext-fiber > > Fibers are a complex feature. The RFC contains many examples and links to > code using fibers to help explain and demonstrate what is possible, however > I’m certain many more questions and concerns will arise. Looking forward to > feedback and discussion. > > Aaron Piotrowski > Hi Aaron, this is a very interesting and welcome piece of functionality. I have gone through the RFC a few times now, it have never thought about or worked with fibers before, additional feedback will be forthcoming once I grasp the details more. >From my POV the effects on other extensions are the most important factor, you already have a section with that for Xdebug, Parallel, and pcov. But how does this affect Profilers that manage their own stack of frames, either all function calls or specifically selected ones. I.e. xhprof, tideways, datadog, newrelic and so on. At the moment any PHP Profiler only has to manage a single stack of "open frames". With Fibers for each fiber a new stack must be opened. Does an extension know what the "active" fiber is so that from a zend_execute_data I know on which stack of open frames I need to push a new frame? Could you add a section to the RFC explaining how a switch between fibers works in terms of "the next" and "previous" zend_execute_data that is run? This would also be interesting to understand how stack traces work, for example debug_print_backtrace. > -- > PHP Internals - PHP Runtime Development Mailing List > To unsubscribe, visit: https://www.php.net/unsub.php > >
