ETags are not a panacea

Patrick Mueller - ETags are not a panacea:

"ETags and Last-Modified processing is something you ought to do, if you can afford it, because it does allow for some optimization in your client / server transactions. To be clear, the optimization is that the server doesn't have to send the content it would have sent to the client, as the client has indicated it already has that 'version' of it cached. There is still a round-trip to the server involved. If you're looking for an absolute killer optimization though, you should be looking at Expires and Cache-Control headers.

[...] Expires and friends are killer, because they allow the ultimate in client / server transaction optimization; the transaction is optimized away completely."

DRBD - Distributed Replicated Block Device

"DRBD is a block device which is designed to build high availability clusters. This is done by mirroring a whole block device via (a dedicated) network. You could see it as a network raid-1."

See also:  DRBD for MySQL

The Underbelly of a Web App

Ryan Campbell - The Underbelly of a Web App:

"Since launch, development time now comes in at around 80% (20% goes to support), and only about half of that time is spent implementing features that our users actually see. Here are some of the tasks that aren’t always thought about when making an application, but that eventually need to be considered."

(Via Ryan Eby.) 

Turning OpenOffice.org into a document conversion tool

Dmitri Popov at Linux.com - Turning OpenOffice.org into a document conversion tool:

"JODConverter can help you to unleash OpenOffice.org's file conversion capabilities.

To be able to use OpenOffice.org as a conversion engine, you have to start it as a service. This means launching it without its GUI and making it listen for incoming connections on a particular port. To do this, launch OpenOffice.org using the following command on Linux:

soffice -headless -accept="socket,port=8100;urp;"

Tagging is declarative programming for everybody

Jon Udell - Tagging is declarative programming for everybody:

"Among other things, tagging may become to ordinary folks what attributes are becoming to programmers: a language that doesn’t just describe things, but also invokes and coordinates behaviors."