Robust Modbus slave simulator

2008/12/1 Nenad Milasinovic <email address hidden>:
> New question #53103 on libmodbus:
> https://answers.launchpad.net/libmodbus/+question/53103
>
> Hi,
>
> I have some questions about libmodbus library.
> I am searching for Modbus slave implementation which will serve as test tool for testing Modbus SCADA master in extreme critical conditions.
> I need Modbus slave implementation which is capable to handle at least 10000 analog values per second (requests for read/write data from 10000 registers per second).
> Assume that we have transport mechanism and CPU capable to support this kind of load, does libmodbus library will be able to support it?
>
> Thanks in advance.

The modbus protocol defines a delay between the characters, my
implementation is a bit different, I use this delay only if required
(I don't wait for next char if it's already there).
To measure my libmodbus performance, the best is to run
./bench-bandwidth-slave and ./bench-bandwidth-master on your machine
to check the results (in /tests).
I obtain around 12 000 registers/second on my laptop with an TCP/IP connection.

The load is more I/O bound than CPU bound.