[Interest] QProcess performance issues

[René J.V. Bertin]

On Thursday May 14 2015 20:56:33 Thiago Macieira wrote:

>> Anyway, I can't remember, esp. not what exactly happens in popenEx(). I've
>> linked to the code, so you can look that up just as easily as I ...
>
>I did. You didn't do what is the cause of the problem: the non-blocking part 
>of it.

OK, I thought you were asking me if I did asynchronous writing ... and I tend to associate that with at least perceptually higher performance ("feels faster"). Curious that it apparently has the adverse effect here ... but I've learned it's best to avoid that kind of sentiment when MS Windows is involved ;)
Does a typical Unix popen implementation use non-blocking writes? If so, there may be a reason Microsoft didn't use it in their implementation ...

So the lesson here would be that if you're going to be piping into (or from) an external application through QProcess on MS Windows, you'll want to do it from a background thread that acts as a buffer?

R.