Comments on: Revving Filenames: don’t use querystring

By: Łukasz Korzybski

Łukasz Korzybski — Mon, 08 Dec 2008 13:31:20 +0000

Great test! It ultimately shows that more conservative approach which is file name versioning is a more safe method (at least now).

By: murray

murray — Wed, 27 Aug 2008 19:20:50 +0000

fyi: squid is capable of caching URLs with query strings, it just wasn’t default behavior due to:

hierarchy_stoplist cgi-bin ?
acl QUERY urlpath_regex cgi-bin \?
cache deny QUERY

squid actually changed their default policy with caching dynamic URLs with their 2.7 release:

http://wiki.squid-cache.org/ConfigExamples/DynamicContent

1 big caveat tho, their dev team told me this will break if you’re using multiple squid nodes with sibling relationships. requests coming from cache peers have an additional header which will hang the request.

By: Yusuf Goolamabbas

Yusuf Goolamabbas — Mon, 25 Aug 2008 13:00:56 +0000

Steve, From my memory HTTP/1.0 keepalives and HTTP/1.1 persistent connections are slightly different.

HTTP/1.0 kept-alive connections must be broken after every dynamic object
HTTP/1.0 doesn’t support pipelining
HTTP/1.0 keepalives is not allowed when one speaks through a proxy.

my experience with squid has been primarily as a reverse proxy and even when I turned
client_persistent_connections on
server_persistent_connections on

Squid did not reuse the connections in all cases
Basically, Squid can’t persist the client-side connection unless it gets a Content-Length: header from the backend.

By: Moushumi Kabir

Moushumi Kabir — Mon, 25 Aug 2008 04:52:45 +0000

This is very useful information. Thanks!

By: Steve Souders

Steve Souders — Sun, 24 Aug 2008 16:04:43 +0000

Great comments. The example from Wufoo is awesome.

Yusuf - I’m assuming HTTP/1.0 is still using persistent connections (connection: keep-alive). How does that affect the 3way handshake?

By: Yusuf Goolamabbas

Yusuf Goolamabbas — Sun, 24 Aug 2008 15:31:14 +0000

Steve, HTTP 1.0 will also cause a tcp 3way handshake to occur for each and every request. It would be interesting to benchmark a page which has many responses (think JSON or XML via XHR) fronted by reverse proxy which can switch between HTTP 1.0 and HTTP 1.1 (lighty 1.5) or comparing squid versus nginx.

it gets more interesting if you put a traffic modellor to emulate a high latency connection between client and proxy so the time taken by the 3way handshake starts to dominate

By: Charlie Park

Charlie Park — Sat, 23 Aug 2008 23:11:54 +0000

Kevin Hale, from Wufoo, has a piece on automatically versioning files. Although I haven’t implemented his code on any of my sites, it looks promising, and works with the non-querystring filename version promoted here.