OutOfMemoryException from Thread.Start

Hi,

I have an embedded board with a PXA 270 chip. It has a Win CE 5.0 OS image
loaded and it supports CF v1. My task was to write a component which
applications will use to transmit objects/structures to other application
across the network. This component will be used by applications running on
the board i mentioned above as well as in normal PC applications. This is the
reason why i couldn't use .NET Remoting - CF does not support it.
Consequently, i have written a component in C# which provides the following
functions:
- send a structure to a remote endpoint
- receive a structure from a remote endpoint

This is how i have implemented it:
- On sending, the component serializes the object in wants to send into a
stream of bytes (packet) first and then sends it by calling the Socket
object's synchronous Send() method. Before returning, this send process needs
to make sure that the other end received the packet (this is where the
reliability part comes into the picture). To know that a packet was received
correctly, the send process waits 200ms (RTO - ReTransmissionTimeout) for an
ACK packet to come back (the reception of this ACK packet is explained below
in the receive section**). If it doesn't receive an ACK by then, it resends
the same packet. It continues to resend the packet every 200ms for 30 secs.
If it still hasn't received it by then, it disconnects the connection to the
remote endpoint.

- On receiving, bytes are received asynchronously by calling the Socket
object's BeginReceive() and EndReceive() methods. The receiving process
blocks until bytes become available on the receiving port. So when bytes do
become available on the receiving port, they are read and deserialized back
to the original object. In order not to miss any further incoming bytes, the
currently received object is passed to another thread for processing. Hence
the receiving process can return and call BeginReceive() again and wait for
more bytes to come in.
Now, the new thread that just got spawned will process the packet. This
component is now being tested with a TestServerApplication (runs on my dev
PC) and a
TestClientApplication (runs on the PXA board). The server simply waits for
clients to connect. When
the client connects, the server accepts it and waits. The system was set up
such that the client app sends a 2KB packet to the server and the server
basically echoes it back. When the client receives the echo, it also echoes
that back and so they play "packet tennis". This is simply to test the
component. The size of an ACK packet is 44 bytes. So this is what happens:

- client sends 2KB to server
- server receives and sends a 44-byte ACK, and then the echo 2KB packet to
the client
- client receives the ACK (which ends the first send), and then also
receives the echoed packet... client then sends an ACK to the server, as well
as the echo packet
- and the process repeats...

Now, the problem i am having occurs on the PXA side. At some random point in
time, when a structure is received and it is passed to another thread for
processing, an OutOfMemoryException occurs when calling Thread.Start(). So i
thought, ok maybe there isn't much RAM, but then i ran it again with the RAM
settings opened (the Control Panel item showing how much Storage Memory and
Program Memory the system has). While the app runs, the amount of RAM
decreases but when the exception occurs, there seems to be a few MBs left of
program memory... how could this exception have been raised? Thanks...

I have written a client application in C# The board will be used to run a
client application which will connect
.

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