Multi threaded libraries on a web farm

I have a library I wrote that launches several threads in the background and
then uses locks to prevent other threads from interferring with them while
they do some work. All of them are simply querying a database and building up
lists of results. This works fine on the development platforms, which are
single server IIS 6 installations. However when we tried to put it on a web
farm, we began to get a windows login box at times when one thread may be
waiting on another to complete. Is this an expected problem? I did have
questions about this working on the web farm, but was not able to find any
articles indicating it would not? Any thoughts on the matter?

Thanks,

Bill

Re: Multi threaded libraries on a web farm

On Nov 19, 12:38 pm, wdudek wrote:
> I have a library I wrote that launches several threads in the background and
> then uses locks to prevent other threads from interferring with them while
> they do some work. All of them are simply querying a database and building up
> lists of results. This works fine on the development platforms, which are
> single server IIS 6 installations. However when we tried to put it on a web
> farm, we began to get a windows login box at times when one thread may be
> waiting on another to complete. Is this an expected problem? I did have
> questions about this working on the web farm, but was not able to find any
> articles indicating it would not? Any thoughts on the matter?
>
> Thanks,
>
> Bill


There is no inherent problem with multi-threaded libraries and a web
farm. For example, ASP.Net and its Session State Service is a good
example of such a working system where multiple threads from multiple
machines can synchronize authenticated access to a SQL database and be
consistent.

Without knowing the design/implementation of your library, it is hard
to determine what is wrong with it.


//David
http://w3-4u.blogspot.com
http://blogs.msdn.com/David.Wang
//

Re: Multi threaded libraries on a web farm

Hi Bill,

If application prompts with Windows login dialog, it's most likely you meet
authentication issue on the deployment.

Could you please provide more detailed information of the application's
design and architecture? Also, if this is an authentication issue, there
should be some corresponding records logged into IIS log files:
\System32\LogFiles\W3SVC[n]\ directory (n here is the Site ID which can be
viewed in the right panel by clicking Web Sites folder in IIS). You can
reproduce the issue again and post the recent log content here. We will
help on reviewing it.

Have a nice day.

Sincerely,

WenJun Zhang

Microsoft Online Community Support

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Re: Multi threaded libraries on a web farm

Thanks, my first concern was that I was doing something inherently wrong.

"David Wang" wrote:

> On Nov 19, 12:38 pm, wdudek wrote:
> > I have a library I wrote that launches several threads in the background and
> > then uses locks to prevent other threads from interferring with them while
> > they do some work. All of them are simply querying a database and building up
> > lists of results. This works fine on the development platforms, which are
> > single server IIS 6 installations. However when we tried to put it on a web
> > farm, we began to get a windows login box at times when one thread may be
> > waiting on another to complete. Is this an expected problem? I did have
> > questions about this working on the web farm, but was not able to find any
> > articles indicating it would not? Any thoughts on the matter?
> >
> > Thanks,
> >
> > Bill
>
>
> There is no inherent problem with multi-threaded libraries and a web
> farm. For example, ASP.Net and its Session State Service is a good
> example of such a working system where multiple threads from multiple
> machines can synchronize authenticated access to a SQL database and be
> consistent.
>
> Without knowing the design/implementation of your library, it is hard
> to determine what is wrong with it.
>
>
> //David
> http://w3-4u.blogspot.com
> http://blogs.msdn.com/David.Wang
> //
>