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Date: Tue, 20 May 2003 04:52:30 +0300
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Subject: fd patch
From: zeev@zend.com (Zeev Suraski)

Just a last heads up before the release here.  Do we really want this patch 
in?  I think that it was put in a bug-fix release in a rather hasty manner, 
with no real reason.  We've already experienced one crash, there may be 
others - it's a very central piece of code.

Weighing the pros and cons of this patch, it basically fixes a problem that 
isn't new or even unique to PHP, and existed ever since the days of PHP/FI 
2.  The symptoms of this problem arise fairly rarely, in situations where 
there's a combination of a web server that opens a very large number of 
files[*], and an operating system with a libc that can't handle fd's over 
255 (Solaris).  I think that saying that PHP is unusable under Solaris is a 
gross overstatement;  I've been aware of this issue since 1996, and yet, 
I've come across less than a handful of real world cases that experienced 
this problem, versus hundreds of cases that worked flawlessly.  By 
including the patch, we are fixing a problem that affects a very small 
percentage of the userbase on Solaris[*], at the price of a fairly big risk 
in breaking functionality for existing users on ALL operating systems.

To summarize, including it in 4.3.2 (or anything in the 4.3.x series) 
doesn't sound like good math to me.  v5/ZE2 already has a fix for this, and 
considering the urgency level of this issue, the sensitivity of the code it 
touches, and the amount of testing that 4.3.x will get before it gets 
released versus 5.x - waiting for 5 makes much more sense.  For people who 
experience this specific issue, we can provide the patch for 4.3.x on php.net.

I don't mean to start a big thread here - I feel very uncomfortable 
releasing such a sensitive patch with so little testing, and don't exactly 
understand why the problem that it addresses is suddenly so urgent.  If 
there's consensus here that this patch is important for this 4.3.x release, 
so be it - I want to at least voice my opinion before it gets finalized.

Zeev

[*] Namely, users of multithreaded servers that actually use PHP in 
threaded mode, which are relatively few;  And users of Apache, configured 
with hundreds of log files, which are also relatively few.  There might be 
other examples, but the problem certainly does not affect a typical 
Apache/PHP setup.  Specifically, it is NOT correlated in any way to the 
number of include/require files that you have in your application - as long 
as there's one fd under 255 handy, PHP will operate without any problems.