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Apache 2.2.0 Released
ikewillis writes "According to an announcement on apache.org, Apache 2.2.0 has been released. From the announcement: 'This version of Apache is a major release and the start of a new stable branch. New features include Smart Filtering, Improved Caching, AJP Proxy, Proxy Load Balancing, Graceful Shutdown support, Large File Support, the Event MPM, and refactored Authentication/Authorization.' View the ChangeLog or check out the new feature list."
See the docs on stopping and restarting for reference.
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If you plan to rely on graceful restarts, be sure to set MaxChildren appropriately low, proportional to your server request rate, otherwise your config changes will never get picked up.
There are no karma whores, only moderation johns
Anyway, I guess the big question is, how many people will actually adopt 2.2.0. I still remember when 2.0 came out to mostly a yawn as most people kept using 1.3.x. Even today, most of the servers that I come across or administer are still using 1.3.x because unless you were running Windows, 2.x didn't really offer spectacular improvements over 1.3.x, and looking at the changes for 2.(1|2).x (anyone who's going to transfer a >2GB file over HTTP is crazy ;)), I have this feeling that we might see the same 1.3->2.0 inertia.
The change from 1.3 -> 2.0 was a very major one. The entire api was retooled; and for good reason, ap 1.3 had some rather serious deficiencies in the extensibility department (module load order significance, etc). 2.0 saw the birth of the exceedingly well designed APR (Apache Portable Runtime), a module-participation-driven abi ("hooks") and fast stack-unwinding i/o handling ("fitlers"). All good stuff, but slightly less able performance-wise on low-cpu-count hardware (extensibility always comes with a pricetag) and completely imcompatible with any module of even moderate complexity that had previously been written.
Times have changed though. The robustness of the abi design combined with the APR has led to some outstanding modules, such as extensive state awareness and dynamic load-balance adjustment without even USR1-style interruption. None of these capabilities are even remotely plausible under 1.3.
The point is: 2.2 is still the same core api design. Certainly, it contains some enhancements, but the bridge that must be crossed is miniscule in comparison to the 1.3/2.0 transition.
There is still much room for improvement (when isn't there?). For example, mpm looks like a good idea on paper, but how well does it really work in terms of abstracting the process/thread semantics into fairly "pluggable" components? How well can it really work? Thread-based design requires a completely different approach or the end result (treating threads like processes) simply nets you more "accounting" overhead and few significant gains to offset that (yes, I realize it wins on win32 which does not have a light-weight process model).
In the mean time (ie, since the 2.0 release) we've changed the versioning model to the "odds are dev, evens are stable" model. So as soon as 2.2 released, development moved to the 2.3 branch, which will release as 2.4. So, yes, like Perl and Linux and many other things.
As for transferring >2GB files, this comes up many times every day on #apache, and fairly frequently on the mailing lists, so people do actually want to do this.
Folks that are still using 1.3 are missing out on enormous strides forward. The "it still works fine, why should I upgrade" crowd are completely welcome to remain where they are, and we're not going to compel to move, but they are going to miss out on all sorts of cool things, in the name of "it's good enough already." Their loss, not ours.
Apache guy, Open Source enthusiast, runner