I currently have a Windows Service that runs Transactions that are very
Processor/Memory Intensive.  I have a requirement to deploy multiple
instances of the Web service on the Same server. Each Instance needs to
run in its own process.

My current approach to this is to put all the logic into a separate
"Worker" assembly and install it into the GAC. I'm then going to create
Multiple Windows Services (i.e. MyService1, MyService2 etc..) that each
instantiate  "Worker" . I will then have a separate install program for
each Windows Service. (Not exactly elegant)

Any suggestions on this approach?

Is there any Way to have one "codebase" for the Windows Services rather
than having a project for "MyService1", "MYService2" etc..?

Does having the "Worker" assembly in the GAC affect performance at all?

Is there an easy way to install Multiple versions of the same Windows
Service on the Same server (I can't seem to find one)


Thanks in advance !!!

John,
You could have the same "Codebase" as you describe it provided the
ServiceName property of each is loaded from the app.Config file in an
appSettings Section. This must be different for each service. However, I am
wondering why you really need multiple instances of the same service.
Wouldn't you be able to use one service and have it use some sort of metadata
or a Hashtable of "rules" and multiple threads to perform the different
functions all from one service?
Peter

Show quoteHide quote

Peter,
The reason for Multiple instances of the same service is for
performance and throughput.  Each instance of the Windows service will
run exactly the same set of Transactions/functions. The services pick
up requests that come in through a Message Queue and process them. The
current version of the Windows service is Multithreaded and handles
multiple requests "simultaneously". One problem with the current
version (one Windows Service) is that we are limited  to the number of
threads that can run  because we run out of  addressable memory (each
thread loads many Instances of Excel Emulators etc...) .The thought is
that multiple process  will allow us to run more Instances
simultaneously

Thanks For your help!

John,
Ok, well that sounds logical on its face, but I question whether in practice
it would help. After all, you have a fixed amount of addressable memory space
on the machine. If you run more processes as a workaround, would that not
actually take up even more memory from the get-go?
Peter

Show quoteHide quote

I was told that each process would have its own address space and this
would help  us avoid the OutOfMemoryException we receive when running
to many threads.  If that is not the case then we have less incentive
to have multiple processes running.

Thanks!

I am no expert in this area. There is some useful info on MSDN here:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/memory/base/4gt_ram_tuning.asp

Also, 64-bit machines / OS  are getting pretty cheap these days - and that
can make a big difference, even for 32-bit apps.

Best of luck.
Peter

Show quoteHide quote

Running 5 separate processes with each 10 threads or running a single
process with 50 threads will take at least the same amount of physical RAM.
But your problem does not relate to physical memory, it relates to virtual
memory and this will always be a problem if you don't "manage your memory"
consumption. That means that you have to restrict the number of threads,
each thread takes 1MB of stack space, each service runs at least 5 threads
before you even create a thread of your own.
Also don't think that more threads means higher performance, most of the
time it's the inverse.
For IO bound processes you can have some more threads running than for
compute bound process. A golden rule is to have at most 2 compute bound
threads per CPU, and up to 20 IO bound threads per CPU. When your threads
are mixed IO/compute, the number may vary between 2 and 20, depending on the
time spend waiting for IO completion. Note that the above figures are not
carved in stone, they are just an indication based on experience, you should
always measure your throughput/performance.
Another question, did you ever profile your memory consumption, are you sure
you dispose your instances and release all unmanaged resources when done
with them?
What version of the framework and OS are you running, and what's your memory
consumption (managed/unmanaged), do you create large objects? and finally
how many threads do you create?


Willy.

Making my DateTime object think its American :-)
Can't set ConnectionStringSettings.ConnectionString property
HttpWebRequest
Interacting with an external process.
.NET Framework Version Conflict