Ruby Forum Ruby > best-performing Rss parser

Posted by Ray Chen (varac)
on 19.08.2006 09:16
Hi all,

I am working on a project that requires rss parsing for pre-fetched web 
pages.  I don't need caching or anything fancy, just the rss parsing 
itself.  I am currently using sporkmonger's feedtools, but I am 
wondering if anything out there is better in terms of performance. 
Hopefully someone has tested a few parsers.  If not, I'll run some 
simple tests and post back to the list.  Some parsers under 
consideration:

http://raa.ruby-lang.org/project/rss/
http://simple-rss.rubyforge.org/
http://sporkmonger.com/projects/feedtools/

Thanks
Ray
Posted by Ray Chen (varac)
on 19.08.2006 09:33
Posted by Bob Aman (Guest)
on 20.08.2006 04:16
(Received via mailing list)
> One more.
> http://syndication.rubyforge.org/doc/

Right now, I'm recommending that people who care about performance use
the UFP instead.

Cheers,
Bob Aman
Posted by Ray Chen (varac)
on 28.08.2006 20:04
Just wanted to give everyone who's curious an update on this situation.

I ended up comparing just Feedtools and Syndication, since the others 
were not as feature-complete as I would have liked.

In our system tests, Syndication performs a lot better than Feedtools, 
but I won't publicize the results here since those are specific to our 
system.

In just the parsing portion of parsing 
http://www.digg.com/rss/chandrasonic/index2.xml (grabbing 40 entries, 40 
titles, 40 dates, etc etc) Syndication took 0.062467 seconds of total 
time and Feedtools took 4.227067 seconds of total time.  This level of 
performance difference is highly reproduceable and I am using this 
specific feed just to show some numbers.

Syndication does have some downsides however.  The programmer must 
specifically whether a feed is RSS or Atom since Syndication has no 
built-in distinguishing mechanism.  Syndication also seems to have 
incomplete time-stamp support.  Slashdot time stamps, for example, 
doesn't work for me.

Disclaimer: I'm not an expert on Ruby, RSS feeds or benchmarking, but 
just wanted to share my results.  Thanks Bob for all your help along the 
way.
Posted by Bob Aman (Guest)
on 05.09.2006 00:34
(Received via mailing list)
> http://www.digg.com/rss/chandrasonic/index2.xml (grabbing 40 entries, 40
>
> Disclaimer: I'm not an expert on Ruby, RSS feeds or benchmarking, but
> just wanted to share my results.  Thanks Bob for all your help along the
> way.

The results aren't even remotely suprising to me, but yeah, they
really underscore several points:

1) REXML is a performance stinker (and by extension, FeedTools 10x more 
so)
2) If performance is an issue, a parse-at-all-costs parser is going to
be a problem unless it's written in C or something similarly fast
3) As always, use the right tool for the job -- FeedTools isn't going
to scale, so if you need scalability, don't use it
4) If you're dealing with ~500 feeds or less, you want to always get
the right answers back, you don't mind the size of the library, and
you want a Ruby-only solution, FeedTools is what you want

In case it's not obvious, point #4 has a lot of conditions.

At some point in the distant future, I intend to write a pure C
library that -will- scale, but that's a long way off, because for the
forseeable future I'm going to be working on GentleCMS.

Cheers,
Bob Aman
Posted by Sunil Khedar (sunil)
on 31.01.2008 09:20
Hi Bob,

I am working on a RSS parser script. Here I have to parser thousands and 
thousands of RSS feeds every hour.

I am looking for a optimized parser which can take parse all these 
feeds. Please suggest the RSS parser you have come across.

Thanks in advance.

Posted by Marco Colli (collimarco)
on 14.02.2009 14:25
Sunil Khedar wrote:
> Hi Bob,
> 
> I am working on a RSS parser script. Here I have to parser thousands and 
> thousands of RSS feeds every hour.
> 
> I am looking for a optimized parser which can take parse all these 
> feeds. Please suggest the RSS parser you have come across.
> 
> Thanks in advance.

Hi, I am looking for an high-performance parser too.
Have you come across any solution?

Thanks!
Posted by Thomas Sawyer (7rans)
on 14.02.2009 16:06
(Received via mailing list)
On Feb 14, 8:24 am, Marco Colli <collimarc...@gmail.com> wrote:
>
> Hi, I am looking for an high-performance parser too.
> Have you come across any solution?

If speed is the #1 issue, I would try libxml-ruby. It's lower lever
then you might want, but that gives you a choice on how to parse, and
it's not be hard to build an rss specific layer on top of that if you
really want it.

T.
Posted by Michael Fellinger (Guest)
on 15.02.2009 12:35
(Received via mailing list)
On Sat, Feb 14, 2009 at 10:24 PM, Marco Colli <collimarco91@gmail.com> 
wrote:
>
> Hi, I am looking for an high-performance parser too.
> Have you come across any solution?

http://www.rubyinside.com/feedzirra-a-new-ruby-feed-library-built-for-speed-1485.html

^ manveru
Posted by unknown (Guest)
on 16.02.2009 04:50
(Received via mailing list)
have you tried vtd-xml (http://vtd-xml.sf.net)
----- Original Message -----
From: "Michael Fellinger" <m.fellinger@gmail.com>
To: "ruby-talk ML" <ruby-talk@ruby-lang.org>
Sent: Sunday, February 15, 2009 3:33:01 AM GMT -08:00 US/Canada Pacific
Subject: Re: best-performing Rss parser

On Sat, Feb 14, 2009 at 10:24 PM, Marco Colli <collimarco91@gmail.com> 
wrote:
> 
> Hi, I am looking for an high-performance parser too. 
> Have you come across any solution? 

http://www.rubyinside.com/feedzirra-a-new-ruby-feed-library-built-for-speed-1485.html

^ manveru
Posted by Tony Arcieri (Guest)
on 17.02.2009 03:59
(Received via mailing list)
On Thu, Jan 31, 2008 at 1:20 AM, Sunil Khedar <sunil@truesparrow.com> 
wrote:

> I am working on a RSS parser script. Here I have to parser thousands and
> thousands of RSS feeds every hour.
>
> I am looking for a optimized parser which can take parse all these
> feeds. Please suggest the RSS parser you have come across.
>

Sounds like a case of premature optimization to me.  If you intend to do
anything like stick the data parsed from the feeds into a database or 
search
index, I think you'll quickly find that will become the bottleneck, 
rather
than the feed processing itself.

My company went through something similar, with a performance obsessed
former C++ programmer looking for the fastest feed parsing solution
available.  He settled on building his own, highly procedural feed 
processor
around libxml-ruby after benchmarking several of the solutions 
available.
However, soon after he discovered that updating the database and search
index was a far bigger bottleneck, one he spent the next several months
addressing.  Feed parsing speed went completely by the wayside.

If you intend to do any sort of indexing of the feeds at all, you should
really focus on building a maintainable feed reader, as opposed to a 
fast
one.  The database and/or search index are going to be your bottleneck
anyway, so don't let the desire for speed trump things like correctness 
and
code clarity.  Feed processing is something that scales horizontally 
using a
queue and multiple feed reader processes, as opposed to databases and 
search
indexes which generally don't scale quite as well.

Given that, I would suggest looking at existing solutions like feedtools 
and
feedzirra before trying to write your own, and if you do, go with 
Nokogiri.
It has a nice, clear, easy-to-use API and is relatively fast.
Posted by Ben Woosley (empact)
on 17.02.2009 08:10
(Received via mailing list)
Tony Arcieri wrote:
> On Thu, Jan 31, 2008 at 1:20 AM, Sunil Khedar <sunil@truesparrow.com> wrote:
>   
>> I am working on a RSS parser script. Here I have to parser thousands and
>> thousands of RSS feeds every hour.
>>
>> I am looking for a optimized parser which can take parse all these
>> feeds. Please suggest the RSS parser you have come across.
>>     

Check out Paul Dix's Feedzirra.  It's an order of magnitude faster than
the alternatives.