[R-SIG-Mac] R-SIG-Mac Digest, Vol 261, Issue 2

[Duncan Murdoch]

On 2024-12-11 3:43 p.m., Michael Hall wrote:
> 
> 
>>
>> Message: 1
>> Date: Wed, 11 Dec 2024 12:25:42 -0500
>> From: Duncan Murdoch <murdoch.duncan using gmail.com>
>> To: R-SIG-Mac <R-SIG-Mac using r-project.org>
>> Subject: [R-SIG-Mac] R.app not handling events
>> Message-ID: <bdf048f1-b010-4845-a67a-f24edf6345be using gmail.com>
>> Content-Type: text/plain; charset="utf-8"; Format="flowed"
>>
>> Every now and then R.app stops responding to various events while a
>> long-running command is executing.  I can't scroll the console to look
>> at earlier results, and I don't see partial results until the whole
>> computation is complete.  If I ask MacOS to switch to that window, it
>> won't come to the top (though clicking on it does bring it up, but I
>> need to be able to see part of it to do that).
>>
>> Once it finishes it returns to the console prompt and things look fine,
>> but the same thing happens during the next long-running command.
>>
>> This happens every now and then, but I haven't spotted the cause.  The
>> only solution I've found is to quit the session and restart it.
>>
>> Does anyone know what might be causing this, or a way to fix it without
>> ending the session?
>>
>> Duncan Murdoch
>>
> 
> You could maybe look at what the app shows on Activity Monitor. Is it doing anything? CPU, IO?
> 
> You can spin dump from there but I’ve never found that particularly revealing.

It's definitely still working.  The typical situation where I've seen 
this lately is when doing some web scraping with RSelenium.  Sometimes 
it takes 10 minutes to visit all the pages and find the info I'm after 
(not because it's a lot of downloading, it's because the site is very 
slow).

Normally my code prints status reports as it goes so I can tell what's 
happening in the console.  When things are in the broken state, those 
don't show up until everything is done.  But I can still see the 
controlled copy of Chrome visiting pages, so I know it hasn't crashed. 
It doesn't seem any slower, it's just that there are no updates in the 
console or responses to user interaction while the command is running.

Duncan Murdoch