Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:79919
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: unknown (pb1.pair.com: domain php.net does not designate 82.113.146.227 as permitted sender)
Date: Wed, 24 Dec 2014 11:16:53 +0000 (GMT)
To: Stanislav Malyshev <smalyshev@gmail.com>
cc: Jacob Bednarz <jacob.bednarz@gmail.com>, internals@lists.php.net
In-Reply-To: <5499E5A4.2080106@gmail.com>
Message-ID: <alpine.DEB.2.11.1412241115530.4080@whisky.home.derickrethans.nl>
References: <etPan.5499de89.643c9869.3ddc@Jacobs-MacBook-Pro.local> <5499E5A4.2080106@gmail.com>
User-Agent: Alpine 2.11 (DEB 23 2013-08-11)
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Subject: Re: [PHP-DEV] Line profiler for PHP
From: derick@php.net (Derick Rethans)

On Tue, 23 Dec 2014, Stanislav Malyshev wrote:

> > The questions I have are: - Is this even possible?
> 
> Yes, should be possible but:
> 1. If you want precision, it would slow down your code a lot, as
> basically you need to record timing of each opcode, which can be very
> expensive.
> 2. If you're ok with less precision, you can do sampling, but in that
> case you probably need your script to spend a lot of time in the same
> areas of the code to have any meaningful results, otherwise it'd be just
> random.
> 
> > - Are there any projects out there or being worked on that achieve
> > this?
> 
> Most of the profilers afaik go by functions. Most probably because
> line-level profiling would be so intrusive as to not produce really
> valid results, but maybe it can be done in a way that is not that
> intrusive.

I have played with it for Xdebug, but it was too much of a slow down to 
be of any use...

cheers,
Derick

-- 
http://derickrethans.nl | http://xdebug.org
Like Xdebug? Consider a donation: http://xdebug.org/donate.php
twitter: @derickr and @xdebug
Posted with an email client that doesn't mangle email: alpine