Re: Hunting for a memory leak

If you comment out show_drawing($MW, $ZC); in makeReviewScreen() the leak goes away. So look in show_drawing()

If you comment out the Photo:

    my $img = 'fred'; # $MW->Photo(
#        -data => encode_base64( $small->png ), -format => 'png'
#    );
[download]

The leak goes away.

If you replace the -data option with a -file option and load a small image straight off disk, each iteration leaks by approximately the size of the loaded image.

Conclusion: Tk::Photo doesn't clean up its memory when you undef the Photo object.

I tried adding $img->blank; before the undef, but it made no difference.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

The start of some sanity?

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Re^2: Hunting for a memory leak by perldough (Sexton) on Aug 07, 2012 at 17:18 UTC
Thank you for this. I believe I need to start doubting the CPAN modules a little more. With your diagnosis, I went to CPAN and found that the bug is already documented. However, contrary to your diagnosis, the documentation says that use of the -file option does not cause this behaviour. Maybe there is something here I can use... Thanks again, Perldough	[reply]
Re^3: Hunting for a memory leak by BrowserUk (Patriarch) on Aug 07, 2012 at 17:30 UTC
contrary to your diagnosis, the documentation says that use of the -file option does not cause this behaviour. Hm. Here are my findings using the -file option: `[18:25:56.31] C:\test>dir test.png 26/05/2012 11:30 7,133 test.png [18:26:17.25] C:\test>986015.pl start perl.exe 6476 Console 1 29 +,328 K end start perl.exe 6476 Console 1 34 +,652 K end start perl.exe 6476 Console 1 38 +,348 K end start perl.exe 6476 Console 1 38 +,180 K end start perl.exe 6476 Console 1 39 +,324 K end start perl.exe 6476 Console 1 42 +,816 K end start perl.exe 6476 Console 1 45 +,948 K end` [download] With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. The start of some sanity?	[reply] [d/l]
Re^4: Hunting for a memory leak by perldough (Sexton) on Aug 08, 2012 at 14:10 UTC
I didn't mean to challenge your finding; rather, I meant to imply that I could maybe look for a way of coaxing my code into exhibiting the behaviour posted in the bug report in order to eliminate the leak. I any case, thanks for taking the time for confirming this. Perldough	[reply]
Re^5: Hunting for a memory leak by BrowserUk (Patriarch) on Aug 08, 2012 at 14:20 UTC
Re^3: Hunting for a memory leak by BrowserUk (Patriarch) on Aug 07, 2012 at 18:30 UTC
Looking in the POD for Tk::Image it says: CAVEATS It's necessary to use the "delete" method to delete an image object and free memory associated with it. Just using a lexical variable for storing the image object and letting the variable to go out of scope or setting to undef is not sufficient. That said, I tried adding `$ZC->centerTags($dwg); $img->delete; undef $img;` [download] And it made no difference. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. The start of some sanity?	[reply] [d/l]
Re^3: Hunting for a memory leak by Anonymous Monk on Aug 08, 2012 at 03:13 UTC
Thank you for this. I believe I need to start doubting the CPAN modules a little more. Tk modules are notorious for leaks -- also , if the module builds any kind of tree, and grepping the source for "weak" returns no hits, 97/100 its leaking :)	[reply]
Re^4: Hunting for a memory leak by perldough (Sexton) on Aug 08, 2012 at 14:19 UTC
That's interesting. Would you mind explaining why that is? Perldough	[reply]
Re^5: Hunting for a memory leak by Anonymous Monk on Aug 10, 2012 at 07:44 UTC


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