100,000 calls a minute to a web service

[kebalex]

Hi,

I've got a requirement to poll a web service for data but it needs to
be done very frequently. The web service call is straight forward, it
just returns a simple table of data with no more than 50 rows. It's a
third party web service so i have no control over it. The problem is
each call is on a per user basis and the client said if its succesful
it there could be 100,000 users. The frequency of each call could be
once a minute so that could be 100,000 calls a minute.

I'm designing the client app to make the calls and i'm thinking each
call should be asynchronous but i'm not sure this is enough. I've got
no experience of multi-threaded development so i'm not sure if this
would help (making the requests over many threads).

Also I'm concerned about bottlenecks. If the app I built was capable
of making 100000 requests a minute (possibly at the same time if its
multi-threaded) then would the network handle this load and also could
the web service handle this many requests at once (i know the W3C
recommends only 2 client connections at once so that could be an
issue).

Anyway, any help or thoughts would be much apprecieated.

Thanks,
Alex

[John Saunders [MVP]]

<ke*****@gmail. comwrote in message
news:11******** **************@ r29g2000hsg.goo glegroups.com.. .

Hi,

I've got a requirement to poll a web service for data but it needs to
be done very frequently. The web service call is straight forward, it
just returns a simple table of data with no more than 50 rows. It's a
third party web service so i have no control over it. The problem is
each call is on a per user basis and the client said if its succesful
it there could be 100,000 users. The frequency of each call could be
once a minute so that could be 100,000 calls a minute.

I'm designing the client app to make the calls and i'm thinking each
call should be asynchronous but i'm not sure this is enough. I've got
no experience of multi-threaded development so i'm not sure if this
would help (making the requests over many threads).

Also I'm concerned about bottlenecks. If the app I built was capable
of making 100000 requests a minute (possibly at the same time if its
multi-threaded) then would the network handle this load and also could
the web service handle this many requests at once (i know the W3C
recommends only 2 client connections at once so that could be an
issue).

This should be possible without making the service asynchronous.

BTW, every web service is a multi-threaded application, and you need to keep
that in mind. Be _extremely_ careful with any static or shared data.

You may want to look at the pattern of the calls to the web service. For
instance, does the data change with every call from a particular user? With
most calls? Only a few times a day? If it doesn't change much, then you may
be able to use caching.

You may also be able to use knowledge of when the data changes. If you are
able to determine that the data have not changed, then you could return a
simpler "no change" response to the client. This would reduce network
traffic.

I understand that you can't change this third-party web service. However, if
it's useful, you could create a web service of your own that then calls the
third-party service. Your web service could perform the optimizations that
the third-party service does not do.
--
--------------------------------------------------------------------------------
John Saunders | MVP - Windows Server System - Connected System Developer

[Spam Catcher]

ke*****@gmail.c om wrote in news:1190896838 .142975.203730
@r29g2000hsg.go oglegroups.com:

Also I'm concerned about bottlenecks. If the app I built was capable
of making 100000 requests a minute (possibly at the same time if its
multi-threaded) then would the network handle this load and also could
the web service handle this many requests at once (i know the W3C
recommends only 2 client connections at once so that could be an
issue).

Anyway, any help or thoughts would be much apprecieated.

Have you talked to the developer of the original web service? If you're
planning 100K users, are they willing to do some customizations for you?

If not, you could build a service on your end - queue up requests for the
100K users. This way you won't swamp the web service?

[=?Utf-8?B?QWxleCBCb25kIE1DVFM=?=]

Yeah i think i'll speak to the developers of the service to see if they can
write some more API's. I don't think they'll be that pleased about me making
so many requests so i'll see what they say.

Thanks for the help,
Alex