mnot’s Web log

Design depends largely on constraints.” — Charles Eames

Caching

Cache Channels Beta

The stale-while-revalidate and stale-if-error extensions aren’t the only fiddling we’ve been doing with the HTTP caching model. Now that Squid 2.7 is starting to see daylight, I can explain...

published on Friday, January 4 2008 ( 2 comments )

Two HTTP Caching Extensions

We use caching extensively inside Yahoo! to improve scalability, latency and availability for back-end HTTP services, as I’ve discussed before. However, there are a few situations where the plain...

published on Wednesday, December 12 2007 ( 11 comments )

ETags, ETags, ETags

I’ve been hoping to avoid this, but ETags seem to be popping up more and more often recently. For whatever reason, people latch onto them as a litmus test...

published on Tuesday, August 7 2007 ( 7 comments )

The State of Proxy Caching

A while back I wrote up the state of browser caching, after writing a quick-and-dirty XHR-based test page, with the idea that if people know how their content is...

published on Wednesday, June 20 2007 ( 13 comments )

Expires vs. max-age

I occasionally get a question from readers of the caching tutorial about whether to use the Expires header or Cache-Control: max-age to control a response’s freshness lifetime. Some people...

published on Tuesday, May 15 2007 ( 6 comments )

Squid is My Service Bus

The QCon presentation (slides) was ostensibly about how we use HTTP for services within Yahoo’s Media Group. When I started thinking about the talk, however, I quickly concluded that...

published on Sunday, April 29 2007 ( 6 comments )

Squid is My Service Bus

The QCon presentation (slides) was ostensibly about how we use HTTP for services within Yahoo’s Media Group. When I started thinking about the talk, however, I quickly concluded that...

published on Sunday, April 29 2007 ( 6 comments )

Caching Performance Notes

There have been some interesting developments in Web caching lately, from a performance perspective; event loops are becoming mainstream, and there are lots of new contenders on the scene....

published on Monday, August 21 2006 ( 14 comments )

Caching Web 2.0

I just finished my XTech presentation, “Web 2.0 on Speed”. here are the slides [pdf]; I’m going to try to s5 them soon. There isn’t much new in this...

published on Tuesday, May 16 2006 ( 7 comments )

The State of Browser Caching

Updated 2006-06-03 One of the big problems that Web developers have with HTTP caching is that they don’t know how the caches behave; while the specs say one thing, the...

published on Thursday, May 11 2006 ( 20 comments )

Invalidating Caches with POST

Have you ever posted a comment to a blog, found it missing, so you re-posted it, only to find two entries? Annoying, huh? Aaron pinged me the other day...

published on Saturday, February 18 2006 ( 12 comments )

Leveraging the Web: Caching

The first in an occasional series about the real-world benefits of REST and the Web architecture, as applied to HTTP. I used to work for a fairly huge company...

published on Saturday, November 26 2005 ( 5 comments )

Prefetching (again)

There’s been quite a kerfuffle over Google’s Web Accelerator, because it prefetches Web content. It’s amusing to see these issues recycle over time; in the late nineties, prefetching was...

published on Sunday, May 22 2005 ( 1 comment )

Google's Cache-Control Extensions

I happened to look at the HTTP headers returned from Google News just now (what can I say, I’m a HTTP geek), and I noticed something unusual; Last login:...

published on Thursday, May 12 2005 ( 5 comments )

Caching Tutorial Update

I’ve published a revision of the Caching Tutorial for Web Authors and Webmasters, the first non-trivial edit in some time almost since I wrote it in 1998. That said, there...

published on Sunday, February 15 2004

Caching is often enough

I feel compelled to respond to Norm Walsh's thoughts on caching. It's important to distinguish between the capabilities of a specific product (such as WWWoffle) and the technology that it...

published on Saturday, June 28 2003