On 1/13/08, Steve Summit <scs(a)eskimo.com> wrote:
(Though why the
behavior differs for "RD/H" versus "Reference desk/Humanities" is
stranger still...)
Well, they're cached separately. Squid is (by design) far from clever
enough to insert the "redirected from" line.
Anyway, yeah, I can reproduce this. Return headers are fairly unremarkable:
HTTP/1.0 200 OK
Date: Sun, 13 Jan 2008 19:54:28 GMT
Server: Apache
X-Powered-By: PHP/5.1.2
Content-Language: en
Vary: Accept-Encoding,Cookie
Cache-Control: private, s-maxage=0, max-age=0, must-revalidate
Last-Modified: Sun, 13 Jan 2008 19:50:50 GMT
Content-Encoding: gzip
Content-Length: 101721
Content-Type: text/html; charset=utf-8
Age: 29338
X-Cache: HIT from
sq19.wikimedia.org
X-Cache-Lookup: HIT from sq19.wikimedia.org:3128
X-Cache: MISS from
sq26.wikimedia.org
X-Cache-Lookup: MISS from sq26.wikimedia.org:80
Via: 1.0 sq19.wikimedia.org:3128 (squid/2.6.STABLE16), 1.0 sq26.wikimedia.org:80
(squid/2.6.STABLE16)
Connection: close
For the non-stale page:
HTTP/1.0 200 OK
Date: Mon, 14 Jan 2008 04:06:32 GMT
Server: Apache
X-Powered-By: PHP/5.2.1
Content-Language: en
Vary: Accept-Encoding,Cookie
Cache-Control: private, s-maxage=0, max-age=0, must-revalidate
Last-Modified: Mon, 14 Jan 2008 03:25:37 GMT
Content-Encoding: gzip
Content-Length: 95947
Content-Type: text/html; charset=utf-8
X-Cache: MISS from
sq24.wikimedia.org
X-Cache-Lookup: HIT from sq24.wikimedia.org:3128
X-Cache: MISS from
sq21.wikimedia.org
X-Cache-Lookup: MISS from sq21.wikimedia.org:80
Via: 1.0 sq24.wikimedia.org:3128 (squid/2.6.STABLE16), 1.0 sq21.wikimedia.org:80
(squid/2.6.STABLE16)
Connection: close
I don't think this has to do with the browser at all, it's just the
Squid you get. sq19 gave me an old copy, sq24 had to look it up fresh
and so I got a new one. When I visit in Firefox I get (mangled a bit
courtesy of Firebug, but still readable):
Date: Sat, 12 Jan 2008 06:40:38 GMT
Server: Apache
X-Powered-By: PHP/5.2.1
Content-Language: en
Vary: Accept-Encoding,Cookie
Cache-Control: private, s-maxage=0, max-age=0, must-revalidate
Last-Modified: Sat, 12 Jan 2008 06:37:46 GMT
Content-Encoding: gzip
Content-Length: 96660
Content-Type: text/html; charset=utf-8
Age: 157163
X-Cache: HIT from
sq19.wikimedia.org, MISS from
sq39.wikimedia.org
X-Cache-Lookup: HIT from sq19.wikimedia.org:3128, MISS from
sq39.wikimedia.org:80
Via: 1.0 sq19.wikimedia.org:3128 (squid/2.6.STABLE16), 1.0
sq39.wikimedia.org:80 (squid/2.6.STABLE16)
Connection: keep-alive
I get it from sq19 again, this time even older (maybe I requested a
slightly different URL?). Ctrl-F5 in Firefox gets me the same page
consistently from sq19.
Actually, this ties into my last post, doesn't it? Do we purge the
URLs of redirects to the edited page? Looking at the code, I very
much don't see that anywhere. That would explain a fair percentage of
outdated cache hits, if true, given the prevalence of redirects.