Best guidance for WCF instance management

Question

i read about  instance management from this article http://www.tutorialspoint.com/wcf/wcf_instance_management.htm
but still do not understand when one should go for per call , per session and single instance management.
suppose i will develop wcf service which will be consumed by 1000 client and every time traffic will be huge and also few function could be there in my service which may take long time to return response. so guide me which instance mode i should choose.
thanks

Answer 1

Hi Mou_kolkata,
  According to this case, I have shared the corresponding details below:
1.First of all, I just summarize the key points of instance management
(1) Per-Call Service :
default instance activation mode of WCF
every client request achieves a new dedicated service instance
memory consumption is less
(2) Per-Session Service :
Private or confidential session is maintained between the client and a particular service instance
the per-session service offers a new service instance which remains dedicated to each client request and autonomous of all the other instances
(3) Singleton Service :
all client requests independent to each other get connected to the same well-known single instance
it gets disposed only when the host closes down
2.For your case, I suggest you to apply singleton service .because your wcf service consuming more than 100 clients. This service is created just for once when the host is created. In case, the host is not provided with any singleton
instance, the service returns as NULL. The activation mode is at its best when the work amount in each method call is little and no pending operations are there in the background.
for  configuration , set like below :
[ServiceBehavior(InstanceContextMode = InstanceContextMode.Single)]
class MySingleton : ...
Further guidance for service code,host code & client code, you can refer in that link is enough.