Re: [squid-users] squid latency

From: Henrik Nordstrom <hno@dont-contact.us>
Date: Wed, 14 Nov 2001 19:07:05 +0100

Is the client on a LAN connection to the cache, or a slow dialup
connection?

If on LAN then you most likely have I/O performance problems on the
Squid cache. See the response time measurements in cachemgr.

If the client is on a dialup, then it may well be that the cache pushes
the HTML content much faster, leaving no bandwidth to the client for
images..

The issue with how browsers renders tables are also relevant, but there
is no difference if using a cache, hits or misses. The table always has
to be rendered. This is most notable when using Netscape, which
sometimes delays the while table rendration until all content in the
table is downloaded.

If you do measurements, make sure to measure on the exact same page, and
to clear the browsers cache when switching between different connection
methods (direct, Squid, other proxy, ...).

Regards
Henrik Nordström
Squid Hacker

Mohsin Khan wrote:
>
> a-o-a
> Well as far as I have seen some of the
> pages with light gif and small data to send , have no
> such problem with squid , where as pages with heavy
> gifs and Large Data to be thrwon through squid, do
> have som latency. e-g, yahoo.com and its Links are
> very smooth, where as cnn.com andits links....are
> seems to be like they have been stored and then just
> thrown to the client
>
> But this behavior is not specific. One
> more thing, the HITS comes with a latency , where as
> the MISS request comes as it is being fetched by the
> squid. So I mean that when a page is being requested
> by GET the HITS are being stored and than delivered at
> once, where as the MISS is delivered directly, so Data
> is being sent untill all is done..Something like that
>
> GET--->HIT
> --->HIT
> --->HIT
> <---
> where as in case of Miss
>
> GET ---> MISS
> <---
> ---> MISS
> <-----
>
> Some thing like that, well may be the Window size,
> but its starnge, but I do expereince it some times.
>
>
>
> --- Henrik Nordstrom <hno@squid-cache.org> wrote:
> > First one needs to understand where the latency
> > comes from. HTML tables is
> > not the source, neither shoud Squid be.
> >
> > As said previously Squid does not normally wait for
> > the page to be
> > downloaded. I can imagine that the differences in
> > TCP windows and similar
> > things may affect the preceived performance on slow
> > links.
> >
> > A tcpdump log of the traffic between client<->proxy
> > and proxy<->server should
> > reveal some...
> >
> >
> > On Thursday 08 November 2001 15.49, Ahsan Ali wrote:
> > > So is there a way to fix this problem? Anyone with
> > any suggestions?
> > >
> > > -Ahsan Ali
> > > ----- Original Message -----
> > > From: "Alberto Brealey G." <beto@inalambrica.net>
> > > To: <squid-users@squid-cache.org>
> > > Sent: Thursday, November 08, 2001 3:41 AM
> > > Subject: Re: [squid-users] squid latency
> >
>
> =====
> Regards,
> Mohsin Khan
>
> >>>Happy is the who can smile<<<
>
> __________________________________________________
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Received on Wed Nov 14 2001 - 11:20:25 MST

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