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On 07/10/2023 13:59, Alan Snyder wrote:<br>
<blockquote type="cite" cite="mid:0DCC2CCE-F246-42F0-8D07-3D2D50C33D7B@cbfiddle.com">
I’ve been investigating a problem with a long running application
that accumulates an apparently unbounded number of
<div>CVDisplayLink threads. I do not yet have an explanation or a
test case.</div>
<div><br>
</div>
<div>The code that creates and releases CVDisplayLinks looks fine,
but that assumes there are no threading issues.</div>
<div>It looks like there are threading issues.</div>
<div><br>
</div>
<div>Specifically, it appears that the startDisplayLink and
stopDisplayLink methods of<span style="caret-color: rgb(0, 0,
0); color: rgb(0, 0, 0);"> the Objective-C class MTLLayer are
invoked on multiple threads.</span></div>
<div><span style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);"><br>
</span></div>
<div><span style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);">They
are invoked on the AppKit main thread from screen sleep
notifications and blitTexture.</span></div>
<div><span style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);"><br>
</span></div>
<div><span style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);">They
are invoked on the EDT from </span><font color="#000000"><span style="caret-color: rgb(0, 0, 0);">MTLLayer.validate.</span></font></div>
<div><font color="#000000"><span style="caret-color: rgb(0, 0,
0);"><br>
</span></font></div>
<div><font color="#000000"><span style="caret-color: rgb(0, 0,
0);">They are invoked on the Queue Flusher thread
from MTLRenderQueue.flushBuffer.</span></font></div>
<div><font color="#000000"><span style="caret-color: rgb(0, 0,
0);"><br>
</span></font></div>
<div>Perhaps someone familiar with this code could comment?</div>
<div><br>
</div>
</blockquote>
It would be better to being this to client-lib-dev as that is where
the metal pipeline is maintained.<br>
<br>
-Alan<br>
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