OSF DCE Application Development Guide--Core Components

RPC and Other DCE Components
Figure 14-2. Server Application Thread and Multiple Call Threads
Single address space
Server
application thread
The server
remote procedures
executing in
Remote procedure
call thread
call threads
Available
Maximum concurrent calls = 4
(listening for calls)
14.1.1 Remote Procedure Call Threads
In distributed processing, a call extends to and from client and server address spaces.
Therefore, when a client application thread calls a remote procedure, it becomes part of a
logical thread of execution known as an RPC thread. An RPC thread is a logical
construct that encompasses the various phases of a remote procedure call as it extends
across actual threads of execution and the network. After making a remote procedure
call, the calling client application thread becomes part of the RPC thread. Usually, the
RPC thread maintains execution control until the call returns.
The RPC thread of a successful remote procedure call moves through the execution
phases illustrated in Figure 14-3.
Figure 14-3. Execution Phases of an RPC Thread
application
thread
Called
remote
procedure
Remote procedure call
Server
Calling
code
Client
Client
Call thread
RPC thread
1
2
3
4
5
RPC thread
The execution phases of an RPC thread in the preceding figure include the following
operations:
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