I *used* to have broadband.

[Nebulon]

I had broadband; now apparently I do not, and without changing ISPs.
OK, downloads once they start are still fast, but surfing the web?
Forgeddaboudit.

Every page seems to spin for an excessive amount of time before even
*starting* to load. A couple of sites are recurring sources of spurious
"Host unknown" errors. Submission forms (such as this one, at Google
Groups) sometimes spin so long that when it finally responds the server
rejects the submission with one cryptic error message or another (at
GG, it produces a spurious 503 error; at other sites with submission
forms for comments etc. it varies. One site has taken to silently
eating half my submissions without any error message at all.)

Disparate symptoms, but all starting fairly recently and growing slowly
worse. Browser independent (and in particular, not avoided by using
Firefox in place of IE). System is clean -- no viruses, no spyware, no
malware of any kind. AVG, Spybot S&D, Ad-Aware, Rootkit Revealer, and a
ton of other stuff show zilch and have done for months, modulo the odd
tracking cookie.

I'm beginning to suspect that it's either a) my ISP or b) something
wonky in Windows, probably in whatever handles name resolution. There's
nothing unusual about my hosts file though -- it's got very little in
it, save I threw in an "ad.doubleclick.net 127.0.0.1" to weed out the
worst of the flash ads and slow, synchronous ads.

Endless wheel-spinning on page requests gives me fond nostalgia for the
days of dial-up -- not.

Any suggestions?

 

[Guest]

I'm no expert, but any anti-virus firm always advises that you shouldn't have
mor than one anti virus system running. Could you be using 'overkill' ?

 

[Nebulon]

Don wrote:
[snip]

I'm only using the one, Grisoft's AVG personal edition. The
anti-spyware products I use are manually-run scan-and-remove tools,
without anything resident. The only other possibly-relevant security
tool is a software firewall, and I haven't changed anything in its
configuration lately.

That leaves a creeping Windows corruption in (most likely) the DNS
subsystem or an ISP side problem.

 

[Lem]

Don wrote:
[snip]

I'm only using the one, Grisoft's AVG personal edition. The
anti-spyware products I use are manually-run scan-and-remove tools,
without anything resident. The only other possibly-relevant security
tool is a software firewall, and I haven't changed anything in its
configuration lately.

That leaves a creeping Windows corruption in (most likely) the DNS
subsystem or an ISP side problem.

Go to someplace like http://www.dslreports.com/speedtest and find out
what your up/down speed actually is. Do it a few times at different
times of day. Try to use a test location geographically near you.

While you're at dslreports, you can check out comments on your ISP as
well. Check your ISP's customer service pages and/or newsgroups to see
if others are experiencing similar slowdowns.

If the speed is consistently lower than what you've paid for, complain
to your ISP.

 

[Nebulon]

Go to someplace like http://www.dslreports.com/speedtest and find out
what your up/down speed actually is. Do it a few times at different
times of day. Try to use a test location geographically near you.

Download speed tends to consistently be 5Mb/s when I have the chance to
max it out. It was the other day (downloading a JDK).

It's the handshaking that's slow. It seems to be:
a) Slow to look up domain names, with intermittent spurious failures
for known-good names that worked two minutes earlier and work again two
minutes later.
b) Not caching domain name lookups locally, as evidenced by the mere
fact that a name can be working, then not, and then working again in a
very short span of time.
c) Slow to handshake with an HTTP server once it finally manages to get
the thing's IP address. This is sometimes failing (usually timing out)
but far less often than name lookups.

Note that no proxy is being used and firewall/router configuration is
nominal and hasn't changed in ages. A cable repair was conducted in the
area recently, but it involved a physical cable breakage, not routing
equipment or similar, and shouldn't have left any residual wonkiness
behind that would predominantly affect DNS lookups and establishing TCP
connections but no other traffic.

Sequential page loads from a single Web site are showing a wide variety
of pathology that is damned odd, though. Frequent name lookup pauses,
lookup failures, and slow to establish connections (to DNS or the
server) indicate that not only is the establishing of TCP connections
and the lookup of domain names wonky (which could involve ISP
infrastructure), but the maintaining of keepalive HTTP connections
(which is less likely to) and the local caching of DNS (which can't
possibly).

There IS a local problem on my machine somewhere. It just proves
elusive...