On Monday 22 March 2010 10:51:14 pm Tommy Pham wrote: > Threading is one of the 2 two main reasons why I moved to Java & > asp.net (C#). I've built a PHP based web crawler about 10 years ago. > I ran into some problems: cookies, form handling and submission, > threading, and application variables. I later found some solutions > for cookies, form handling & submission. But no solution for > threading and application variables. Thus the move. Here's a simple > example of one of the many uses for threading. For an e-commerce > site, when the shopper requests for a category (ID), you can have a > thread to get all subcategories for that category, another thread to > get any assigned products, another thread to fetch all manufacturers > listed under that category, another thread to fetch any filters (price > ranges, features, specs, etc) set by the store owner that would fall > under that category, etc... versus what PHP currently doing now: > fetch subcategories, then fetch assigned products, then fetch > manufacturers, etc.... Performance would increase ten fold because of > parallel (threading) operations versus serial operations. Add that to > application variable (less memory usage and CPU cycles due to > creating/GC of variables that could be used for an entire application > regardless of requests & sessions), you have an excellent tool. > > Regards, > Tommy Threading is also much more difficult to program for safely, because thread order is non-deterministic. Do you really want to unleash hoards of marginally competent programmers on a threaded enviornment? :-) Also, the architecture you describe above is fine if you're scaling a single server really big. PHP is designed to scale the other direction: Just add more servers. There's no data shared from one request to another, so there's no need to share data between web heads. Throw a load balancer in front of it and spin up as many web servers as you need. The "shared nothing" design is very deliberate. It has design trade-offs like anything else. PHP is a web-centric language. It's not really intended for building tier-1 daemon processes, just like you'd be an idiot to try and code your entire web app in C from the start. --Larry Garfield -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
