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Re: OT: How to tell an HTTP client to limit parallel connections?

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On 2013-11-08, Skip Montanaro <skip@pobox.com> wrote:
>> What I really need is an HTTP header or meta-tag or something that I
>> can use to tell clients to limit themselves to a single connection.
>>
>> I haven't been able to find such a thing, but I'm hoping I've
>> overlooked something...
>
> That will only go so far. Suppose you tell web browsers "no more than
> 3 connections", then get hit by 30 nearly simultaneous, but separate
> clients.

In practice, that doesn't happen.  These servers are small, embedded
devices on internal networks.  If it does happen, then those clients
are all going to have to queue up and wait.

> Then you still wind up allowing up to 90 connections.

The web server is single threaded.  It only handles one connection at
a time, and I think the TCP socket only queues up a couple.  But that
doesn't stop browsers from trying to open 8-10 https connections at a
time (which then eventually get handled serially).

> There should be a parameter in your web server's config file to limit
> the number of simultaneously active threads or processes.

The server is single-threaded by design, so it is not capable of
handling more than one connection at a time.  The connections are
never actually in "parallel" except in the imagination of the browser
writers.

> It's been a long time for me, and you don't mention what brand of
> server you are running, but ISTR that Apache has/had such parameters.

FWIW, it's an old version of the GoAhead web server:

  http://embedthis.com/products/goahead/

> (Also, while this is off-topic for comp.lang.python, most people here
> are a helpful bunch, and recognizing that it is off-topic, will want
> to reply off-list. You don't give them that option with
> "invalid@invalid.invalid" as an email address.)

Yea, trying to hide e-mail addresses from automated spammers is
probably futile these days.  I'll have to dig into my slrn config
file.

-- 
Grant Edwards               grant.b.edwards        Yow! Somewhere in DOWNTOWN
                                  at               BURBANK a prostitute is
                              gmail.com            OVERCOOKING a LAMB CHOP!!

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OT: How to tell an HTTP client to limit parallel connections? Grant Edwards <invalid@invalid.invalid> - 2013-11-08 17:25 +0000
  Re: OT: How to tell an HTTP client to limit parallel connections? donarb <donarb@nwlink.com> - 2013-11-08 09:39 -0800
  Re: OT: How to tell an HTTP client to limit parallel connections? Skip Montanaro <skip@pobox.com> - 2013-11-08 11:39 -0600
    Re: OT: How to tell an HTTP client to limit parallel connections? Grant Edwards <invalid@invalid.invalid> - 2013-11-08 18:01 +0000
  Re: OT: How to tell an HTTP client to limit parallel connections? Chris Angelico <rosuav@gmail.com> - 2013-11-09 05:16 +1100
    Re: OT: How to tell an HTTP client to limit parallel connections? Grant Edwards <invalid@invalid.invalid> - 2013-11-08 19:20 +0000
      Re: OT: How to tell an HTTP client to limit parallel connections? Chris Angelico <rosuav@gmail.com> - 2013-11-09 06:39 +1100
        Re: OT: How to tell an HTTP client to limit parallel connections? Grant Edwards <invalid@invalid.invalid> - 2013-11-08 20:48 +0000
          Re: OT: How to tell an HTTP client to limit parallel connections? Chris Angelico <rosuav@gmail.com> - 2013-11-09 08:01 +1100
            Re: OT: How to tell an HTTP client to limit parallel connections? Grant Edwards <invalid@invalid.invalid> - 2013-11-08 21:14 +0000
              Re: OT: How to tell an HTTP client to limit parallel connections? Chris Angelico <rosuav@gmail.com> - 2013-11-09 08:29 +1100
  RE: How to tell an HTTP client to limit parallel connections? Nick Cash <nick.cash@npcinternational.com> - 2013-11-08 19:42 +0000
    Re: How to tell an HTTP client to limit parallel connections? Grant Edwards <invalid@invalid.invalid> - 2013-11-08 21:02 +0000
  Re: OT: How to tell an HTTP client to limit parallel connections? Ian Kelly <ian.g.kelly@gmail.com> - 2013-11-08 13:13 -0700
    Re: OT: How to tell an HTTP client to limit parallel connections? Grant Edwards <invalid@invalid.invalid> - 2013-11-08 21:05 +0000

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