change 1 service when main application is running

[Daylor]

i have 1 main winapplication.
3 services ,each in dll.

each service is created for telephony user.
each service is destroyed when the telephony user is hangUp.

is there a way to recompile the dll service (to add for example 1 line of
code/fix smale bug/small change ) while the main winappilcation is running.
this is very important.
cause if for example the main appilcation serves 100 telephony users 24
hours. (avg)
i can't shut down the system,disconnect all callers,
just to add 1 lines of code , in specific service (that no caller is
currently using,(at the time of recompiling).

ive try to recompile the dll after i destry the object i created from the
dll and after tell the gc to clean it.

even that, the process is still using the dll.
anyone have other way to solve this problem ?

remember the problem is :
changing 1 serviceONE, while 100 callers r currently using ServiceTwo and
ServiceThree.
than after changing the serviceOne in code ,
i could transfer new caller to the updated serviceOne .
<--all this , while the main application is alway open.

hope im clear.

thanks and have a nice day.

[Jon Skeet]

Daylor <Da****@012.net.il> wrote:

i have 1 main winapplication.
3 services ,each in dll.

When you say "service" here, do you mean Windows service or not?

If you don't, then probably AppDomain unloading is what you're looking
for. You'll need to change things so that each of your DLLs is only
used in its own AppDomain, and provide some way of unloading that
AppDomain when you want to replace the DLL.

--
Jon Skeet - <sk***@pobox.com>
http://www.pobox.com/~skeet/
If replying to the group, please do not mail me too

[Daylor]

hi.
i dont mean Window Service.
there is problem if i create AppDomain in every service.

its mean,that i will have 30 appDomain in the process (or even 100 in near
future).
this is to much i think.

and the second reason,is that , the dll (service object),recived and used
the main classes in the win application.
as i know, passing and using object from diffrent appDomain, is very heavy
and not recommended for this situations.
imagine that every second line of code , will call from the service
appdomain , to the main appdomain.not good i think.(and im talking about 30
/100 appDomains)

any other suggestions ?
"Jon Skeet" <sk***@pobox.com> wrote in message
news:MP************************@news.microsoft.com ...

Daylor <Da****@012.net.il> wrote:

i have 1 main winapplication.
3 services ,each in dll.

When you say "service" here, do you mean Windows service or not?

If you don't, then probably AppDomain unloading is what you're looking
for. You'll need to change things so that each of your DLLs is only
used in its own AppDomain, and provide some way of unloading that
AppDomain when you want to replace the DLL.

--
Jon Skeet - <sk***@pobox.com>
http://www.pobox.com/~skeet/
If replying to the group, please do not mail me too

[Daylor]

ok, im going to try to create the service in appDomain.

what r the diff between class that exist in thread, and class that exist in
appDomain ?

1.passing classes r "expensive".
2.if the appDomain is crush the process is crush too ,not ?
3.i think unloading appDomain (and by that unload the dll),will not work,
cause the problem is not with .Net , the problem is with Win32.
meaning:when u load dll in win32 process. u can't unload it.
4.more main diff between appDomain and threads will be help to know.

thanks for your replies.

"Jon Skeet" <sk***@pobox.com> wrote in message
news:MP************************@news.microsoft.com ...

Daylor <Da****@012.net.il> wrote:

there is problem if i create AppDomain in every service.

its mean,that i will have 30 appDomain in the process (or even 100 in near future).
this is to much i think.

Not sure - I haven't tried it, but it would be worth investigating.

and the second reason,is that , the dll (service object),recived and used the main classes in the win application.
as i know, passing and using object from diffrent appDomain, is very heavy and not recommended for this situations.

It certainly needs to be done carefully. MarshallByRefObject can help a
lot there, if you know what you're doing.

imagine that every second line of code , will call from the service
appdomain , to the main appdomain.not good i think.(and im talking about 30 /100 appDomains)

I don't know - I haven't looked at the performance implications. Have
you? It sounds like it would be at least worth investigating.

any other suggestions ?

Have each service as a separate process, or have some way that you can
start a new process and receive new requests in that process, ditching
the old process when it's no longer being used.

--
Jon Skeet - <sk***@pobox.com>
http://www.pobox.com/~skeet/
If replying to the group, please do not mail me too

[Jon Skeet]

Daylor <Da****@012.net.il> wrote:

ok, im going to try to create the service in appDomain.

what r the diff between class that exist in thread, and class that exist in
appDomain ?
It's not an either/or. *Everything* lives in some app domain, and *all*
code is run in a thread.
1.passing classes r "expensive".
Not necessarily. Marshalling by reference is fairly cheap.
2.if the appDomain is crush the process is crush too ,not ?
Do you mean if the app domain *crashes*? It depends on the way in which
it crashes.
3.i think unloading appDomain (and by that unload the dll),will not work,
cause the problem is not with .Net , the problem is with Win32.
meaning:when u load dll in win32 process. u can't unload it.
Loading a DLL in .NET isn't the same as it is in straight Win32. You
definitely *can* unload an AppDomain and then delete/change the DLLs it
had loaded.
4.more main diff between appDomain and threads will be help to know.

They're completely separate concepts. I suggest you get hold of a good
..NET book such as Jeffrey Richter's Applied Microsoft .NET Programming
which explains it all fairly thoroughly.

--
Jon Skeet - <sk***@pobox.com>
http://www.pobox.com/~skeet/
If replying to the group, please do not mail me too