[Ovmsdev] Console logging / CAN tracing

[Stephen Casner]

Michael,

The right fix is to change the CAN tracing to gather its output into a
buffer so complete lines get logged.

The ESP_LOG macros get redirected through our logging system as well,
but (currently) only to the async console rather than all consoles.
Is logging of CAN traces to telnet/SSH sessions desired?  How about
other logging?

There may also be some ways to improve handling of full-queue
conditions to degrade more gracefully.

                                                        -- Steve

On Fri, 29 Dec 2017, Michael Balzer wrote:

> I've found a strange issue with console logging and/or especially
> CAN tracing:
>
> If CAN tracing is enabled and a and that sends CAN frames and runs
> longer than about a second (?) (i.e. "co can1 scan"), the trace
> output first becomes garbled, the command will need much longer than
> usual to finish, and after returning to the prompt, the hex and
> single char output of the trace is split into separate outputs,
> coming one per second (running for a while), intermixing with the
> shell prompt. Also trace output gets garbled especially on a
> parallel telnet session.
>
> I suspect that's due to the UART queue becoming full, and the
> console logger doing xQueueSendToBack() with 1000 ms timeouts.
>
> Every hex dump byte is logged by a separate call to
> MyCommandApp.Log(). If the queue is full, every single call gets
> delayed for a second ...adding up to block the console for as many
> seconds as there are calls...? (unverified theory)
>
> > As proposed, I will change the script code to use BufferedShell and
> > also change how console_logger() is done so I can remove the
> > problematic OvmsConsole::Log() function.  Then puts() will work again,
> > too.
> >                                                         -- Steve
>
> Is this related? I.e. should the CAN trace output be done using
> ESP_LOG instead of MyCommandApp.Log()?
>
> If so I can take care of that...
>
> Regards,
> Michael
>
> --
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