[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: NadaNet file server coming soon...
On Mar 22, 5:22 pm, "Michael J. Mahon" <mjma...@aol.com> wrote:
> The current implementation is geared to a network of more than two
> machines, and uses a message server to queue the requests. The server
> and client code are easily modified for a two-machine network that
> forgoes queueing (since one client can't have more than one request
> in the queue at a time anyway) and so doesn't need the message server.
>
> The client machine queues a request (prefixed with its machine ID)
> by doing a &PUTMSG to the predetermined file server queue number, then
> idles in a &SERVE() loop polling the result code after each network
> transaction handled by the client. When it finds a result, it returns
> from the GOSUB and continues execution.
>
> The file server idles polling its input queue with a &GETMSG, and, when
> it finds a request, it parses it, sets up any required parameters that
> were not supplied, and executes the command on the local file system.
>
> If a data transfer is required, it is &PEEKed and BSAVEd or BLOADed and
> &POKEd in chunks up to some maximum (like 4KB, to keep network latency
> reasonable). When the command is complete, the result code, and any
> address and EOF information, is &POKEd to the requester, and the server
> goes on to the next request in its queue.
>
> Performance seems to be quite good, limited primarily by device latency
> and/or network bandwidth (>10KB/sec).
Hi Michael,
Interesting approach. I had expected a block-level implementation,
although that precludes serving data to multiple machines (Unless your
server can pull off some pretty amazing locking intelligence).
While it's probably inappropriate to start talking about extensions to
unreleased products, I'll do it anyway :-) One idea would be to modify
the client to use the ProDOS Filing Interface hook, which would enable
it to function transparently for *any* ProDOS application. It begs the
question "where to put it", but I assume disconnecting /RAM and
stuffing it into ALTLC would work just nicely. It's about time
somebody discovered just how 'friendly' developers were to Apple when
respecting the reserved memory areas :-)
Anyway, just a thought, and a way to significantly increase the
utility of the network.
Regards,
Matt