Concurrency issue with latest modification

[lafrank]

Although I think it is a very useful and great work, I also believe - but could be wrong - that there is a serious concurrency issue with latest modification "Update Arduino library for less CPU consumption".

This change has introduced a thread that initiates a timed event that is called in every 30ms to read the serial port, a much better approach than the original code. The problem is however, that the timer will tick and initiate a new call disregarding whether the execution of the previous call has finished or not. This results is multiple, simultaneously running instances of InputProcessor.InputProcess() method.

In my view, InputProcessor.InputProcess() should be enclosed in a Monitor.TryEnter(_serialPort) and Monitor.Exit(_serialPort) try-finally clause to prevent parallel execution.

See pull request #8 for details

[LattePanda]

Laszlo, Really thanks for your kindly help, that would be very helpful for thousands of lattepanda user. Is there any other problem or suggestion about the library or lattepanda? any information will be very helpful. Looking forward to your reply, thanks. Best Regards, Kelvin Sun LattePanda Team www.lattepanda.com<http://www.lattepanda.com>

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________________________________ From: Laszlo Frank <notifications@github.com> Sent: Sunday, June 25, 2017 5:13:45 PM To: LattePandaTeam/LattePanda-Development-Support Cc: Subscribed Subject: [LattePandaTeam/LattePanda-Development-Support] Concurrency issue with latest modification (#7) Although I think it is a very useful and great work, I also believe - but could be wrong - that there is a serious concurrency issue with latest modification "Update Arduino library for less CPU consumption". This change has introduced a thread that initiates a timed event that is called in every 30ms to read the serial port, a much better approach than the original code. The problem is however, that the timer will tick and initiate a new call disregarding whether the execution of the previous call has finished or not. This results is multiple, simultaneously running instances of InputProcessor.InputProcess() method. In my view, InputProcessor.InputProcess() should be enclosed in a Monitor.TryEnter(_serialPort) and Monitor.Exit(_serialPort) try-finally clause to prevent parallel execution. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub<#7>, or mute the thread<https://github.com/notifications/unsubscribe-auth/AQGbkwPZ1W8zlJKXxmFzIRgVLorYs-oaks5sHiTJgaJpZM4OEjrB>.

[lafrank]

Hi Kelvin, Yes, there are a few other modifications what I already pushed to my fork. Only these are not tested so currently I am not creating a pull request. Kind Regards, Laszlo

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On Tue, Jun 27, 2017 at 5:57 AM, LattePanda ***@***.***> wrote: Laszlo, Really thanks for your kindly help, that would be very helpful for thousands of lattepanda user. Is there any other problem or suggestion about the library or lattepanda? any information will be very helpful. Looking forward to your reply, thanks. Best Regards, Kelvin Sun LattePanda Team www.lattepanda.com<http://www.lattepanda.com> ________________________________ From: Laszlo Frank ***@***.***> Sent: Sunday, June 25, 2017 5:13:45 PM To: LattePandaTeam/LattePanda-Development-Support Cc: Subscribed Subject: [LattePandaTeam/LattePanda-Development-Support] Concurrency issue with latest modification (#7) Although I think it is a very useful and great work, I also believe - but could be wrong - that there is a serious concurrency issue with latest modification "Update Arduino library for less CPU consumption". This change has introduced a thread that initiates a timed event that is called in every 30ms to read the serial port, a much better approach than the original code. The problem is however, that the timer will tick and initiate a new call disregarding whether the execution of the previous call has finished or not. This results is multiple, simultaneously running instances of InputProcessor.InputProcess() method. In my view, InputProcessor.InputProcess() should be enclosed in a Monitor.TryEnter(_serialPort) and Monitor.Exit(_serialPort) try-finally clause to prevent parallel execution. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub<https://github.com/ LattePandaTeam/LattePanda-Development-Support#7>, or mute the thread<https://github.com/notifications/unsubscribe-auth/ AQGbkwPZ1W8zlJKXxmFzIRgVLorYs-oaks5sHiTJgaJpZM4OEjrB>. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#7 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AO-XZIN8GfOKFHFNeS5enzSo-ImTWpyJks5sIH2ogaJpZM4OEjrB> .