Re: [gentoo-user] I/net server throttling

[Michael Mol]

On Sun, Jul 1, 2012 at 4:12 PM, Mick <michaelkintzios@×××××.com> wrote:
> On Sunday 01 Jul 2012 20:34:23 Jarry wrote:
>> On 01-Jul-12 21:20, Philip Webb wrote:
>> > I now have an explicit example of a server doing this :
>> >    503: hold> wget --no-check-certificate -c
>> >    http://www.math.wisc.edu/~keisler/keislercalc-2-12.pdf --2012-07-01
>> >    15:07:18--  http://www.math.wisc.edu/~keisler/keislercalc-2-12.pdf
>> >    Resolving www.math.wisc.edu... 144.92.166.196
>> >    Connecting to www.math.wisc.edu|144.92.166.196|:80... connected.
>> >    HTTP request sent, awaiting response... 302 Found
>> >    Location:
>> >    https://www.math.wisc.edu/formMail/throttle.php?URL=/~keisler/keisler
>> >    calc-2-12.pdf [following] --2012-07-01 15:07:18--
>> >    https://www.math.wisc.edu/formMail/throttle.php?URL=/~keisler/keisler
>> >    calc-2-12.pdf Connecting to www.math.wisc.edu|144.92.166.196|:443...
>> >    connected. WARNING: The certificate of `www.math.wisc.edu' is not
>> >    trusted. WARNING: The certificate of `www.math.wisc.edu' hasn't got a
>> >    known issuer. HTTP request sent, awaiting response... 200 OK
>> >    Length: 24184097 (23M) [application/pdf]
>> >    Saving to: `keislercalc-2-12.pdf'
>> >
>> >    6% [==========>                  ] 1,638,400   64.5K/s  eta 38m 5s
>>
>> Everything OK here:
>>
>> obelix ~ # wget --no-check-certificate -c
>> http://www.math.wisc.edu/~keisler/keislercalc-2-12.pdf
>> --2012-07-01 19:35:14--
>> http://www.math.wisc.edu/~keisler/keislercalc-2-12.pdf
>> Resolving www.math.wisc.edu... 144.92.166.196
>> Connecting to www.math.wisc.edu|144.92.166.196|:80... connected.
>> HTTP request sent, awaiting response... 302 Found
>> Location:
>> https://www.math.wisc.edu/formMail/throttle.php?URL=/~keisler/keislercalc-2
>> -12.pdf [following]
>> --2012-07-01 19:35:14--
>> https://www.math.wisc.edu/formMail/throttle.php?URL=/~keisler/keislercalc-2
>> -12.pdf Connecting to www.math.wisc.edu|144.92.166.196|:443... connected.
>> HTTP request sent, awaiting response... 200 OK
>> Length: 24184097 (23M) [application/pdf]
>> Saving to: `keislercalc-2-12.pdf'
>>
>> 100%[======================================>] 24,184,097  6.88M/s   in 4.4s
>>
>> 2012-07-01 19:35:19 (5.25 MB/s) - `keislercalc-2-12.pdf' saved
>> [24184097/24184097]
>>
>> Jarry
>
> Everything OK here too maxing out my ADSL connection (I'm envious of Jarry's
> fibre! :p )
>
> $ wget --no-check-certificate -c
> http://www.math.wisc.edu/~keisler/keislercalc-2-12.pdf
> --2012-07-01 20:54:06--
> http://www.math.wisc.edu/~keisler/keislercalc-2-12.pdf
> Resolving www.math.wisc.edu... 144.92.166.196
> Connecting to www.math.wisc.edu|144.92.166.196|:80... connected.
> HTTP request sent, awaiting response... 302 Found
> Location:
> https://www.math.wisc.edu/formMail/throttle.php?URL=/~keisler/keislercalc-2-12.pdf
> [following]
> --2012-07-01 20:54:07--
> https://www.math.wisc.edu/formMail/throttle.php?URL=/~keisler/keislercalc-2-12.pdf
> Connecting to www.math.wisc.edu|144.92.166.196|:443... connected.
> HTTP request sent, awaiting response... 200 OK
> Length: 24184097 (23M) [application/pdf]
> Saving to: `keislercalc-2-12.pdf'
>
> 100%[======================================>] 24,184,097   821K/s   in 38s
>
> 2012-07-01 20:54:46 (619 KB/s) - `keislercalc-2-12.pdf' saved
> [24184097/24184097]
>
>
> This pretty good given that I am connecting all the way from ol' Blighty and
> there is some latency and potentially dropped packets:
>
> # mtr -c 3 -s 955 -u -l -r wisc.edu
> HOST: dell_xps                    Loss%   Snt   Last   Avg  Best  Wrst StDev
>   1.|-- router                     0.0%     3    4.0 3.9 3.9 4.0 0.0
>   2.|-- b.gormless.thn.aa.net.uk   0.0%     3   43.5  44.9  43.5  46.1   1.3
>   3.|-- a.aimless.thn.aa.net.uk    0.0%     3   45.6  45.0  43.1  46.3   1.7
>   4.|-- 10gigabitethernet1-1.core  0.0%     3   47.7  58.2  45.1  81.9  20.5
>   5.|-- 10gigabitethernet7-4.core  0.0%     3  112.5 112.9 112.5 113.7   0.7
>   6.|-- 10gigabitethernet8-3.core  0.0%     3  131.9 136.3 131.9 139.8   4.0
>   7.|-- ???                       100.0     3    0.0   0.0   0.0   0.0   0.0
>   8.|-- r-uwmadison-isp-xe-8-0-1-  0.0%     3  165.7 166.8 161.1 173.6   6.3
>     |  `|-- 140.189.8.1
>   9.|-- r-peer-xe-1-1-0-945.net.w  0.0%     3  160.0 161.0 160.0 161.9   1.0
>  10.|-- r-cssc-b280c-9-core-vlan-  0.0%     3  161.9 160.4 159.5 161.9   1.3
>     |  `|-- 146.151.167.85
>  11.|-- r-csscplat-b380-1-node-vl  0.0%     3  159.9 160.4 159.6 161.7   1.2
>  12.|-- ???                       100.0     3    0.0   0.0   0.0   0.0   0.0
>
>
> If as I recall you said this happens at all times and it is not related to
> Internet congestion, then all I can suggest is to try using a different ISP's
> network and see if you are getting similar problems.

It could be a connection duration limit. Either the web server or an
intermediate proxy server may place a limit on how long a connection
may be open. If you have a low-bandwidth pipe, you'd be more
vulnerable to hitting that limit than someone with a high-bandwidth
pipe.

Possible sources off the top of my head: PHP scripts' script time
limits. squid connection time limits.

Try launching two simultaneous wget processes, and see if they both
fail out around the same time.



-- 
:wq