A customer recently contacted me regarding an iRule that worked in v 9.4 but
did not produce the expected results in v 10. A little research revealed
that the new plug-in architecture is influencing when the iRule is firing.
The iRule
The iRule is logging the value of the X-PvInfo header or indicating the
header is not present.
when HTTP_RESPONSE {
if {[HTTP::header exists X-PvInfo]}{
log local0. "X-PvInfo:[HTTP::header "X-PvInfo"]"
} else {
log local0. "did not find X-PvInfo header"
}
}
The Problem
WebAccelerator inserts the X-PvInfo header into each and every response that
it processes, there should be no instances where the header is missing
however in v10 the Local Traffic logs on the Big-IP show "Rule LogHeaders
: did not find X-PvInfo header." Looking at the headers
received by the browser I can clearly see that the header does exist... (more)
Being the total acceleration junkie that I am the first time a new site is
launched or recommended to me the first thing I do is take a look at the
performance of it. So when I heard about Bing the first thing I did was
fire up HttpWatch and take a look at the site. To make things a little more
interesting I decided to compare the results to Google, I used the classic
home page and not my customized iGoogle home page.
Tests were conducted from my home broadband connection in London, England.
Each test was done with a fresh instance of the browser and with an empty
browser cac... (more)
I am frequently asked what can be done to accelerate XML. There are two
ways an application delivery controller can accelerate XML:
Compression - XML is a markup language that is text based. Text is easily
compressible and can result in significant savings. Dynamic Caching - If
the XML is repetitive it can be cached, if each and every XML request is
unique then caching is not going to help. Caching rules can be written
based on the URI and request headers, off-loading requests from the origin
servers. Technorati Tags: acceleration,compression,xml
Categories: Acceleration , XM... (more)
This week Keynote Systems announced a Fast Web Race contest. According to
the site the purpose of the contest is to improve the overall performance of
many web sites by sharing best practices and real world examples.
"Everyday we work with Web dev and ops communities and we see a lot of the
same performance issues come up. We think there’s an opportunity to share
best practices with the community using real world examples."
There's nothing better than sharing what you've learned with a community,
isn't that what DevCentral is all about. I am looking forward to seeing the
resul... (more)
Yesterday Google announced a new HTML 5 based tool for web based
communication and collaboration called Wave. One of the coolest things
about Wave is this is an open-source project, anybody can embed waves in
their site and build extensions using the Google Wave API. The protocol
called the Google Wave Federation Protocol is based on XMPP (Extensible
Messaging and Presence Protocol).
Reading the documentation on the protocol I immediately started to think
about what impact these waves will have in environments with Application
Delivery Controllers:
What load balancing method... (more)
Dawn Parzych is a product manager for F5 Networks, the global leader in Application Delivery Networking. For the past 2 years, she has been in London working as an acceleration architect with F5 customers based in Europe, the Middle East, and Africa. Dawn has helped companies in finance, retail, media, and other industries optimize performance levels and overcome Web application delivery challenges. In her ten years as a Web performance specialist, Dawn has covered everything from load testing to Web performance monitoring to application delivery. 
David Lucas
Cathy Lopez
Shaul Efraim
Terence Martin Breslin
Cory Marchand
David Hughes
James Carlini
John Iffert
Dan Stolts
Joe Zeto
