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This is an automatically generated e-mail. To reply, visit:
<a href="https://git.reviewboard.kde.org/r/121861/">https://git.reviewboard.kde.org/r/121861/</a>
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<p style="margin-top: 0;">On January 5th, 2015, 9:37 p.m. UTC, <b>David Faure</b> wrote:</p>
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<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;"><p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">Ah cool, I didn't know the Qt5 implementation of QFSW solved this. Nice.</p></pre>
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<p>On January 5th, 2015, 9:48 p.m. UTC, <b>Ralf Habacker</b> wrote:</p>
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<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;"><p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">The motivation for KFileSystemWatcher is the following limitation:</p>
<ul style="padding: 0;text-rendering: inherit;margin: 0 0 0 1em;line-height: inherit;white-space: normal;">
<li style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: normal;">the maximum number of object handles is MAXIMUM_WAIT_OBJECTS (64) per thread.</li>
<li style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: normal;">"To wait on more than MAXIMUM_WAIT_OBJECTS handles, create a thread to wait</li>
<li style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: normal;">on MAXIMUM_WAIT_OBJECTS handles, then wait on that thread plus the other handles.</li>
<li style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: normal;">Use this technique to break the handles into groups of MAXIMUM_WAIT_OBJECTS."
*</li>
<li style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: normal;">QFileSystemWatcher is implemented as thread, so KFileSystemWatcher</li>
<li style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: normal;">allocates more QFileSystemWatcher instances on demand (and deallocates them later).
*/</li>
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<p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">https://qt.gitorious.org/qt/qtbase/source/73a1e8c60d894701f34806cc4b847aa2814bf389:src/corelib/io/qfilesystemwatcher_win.cpp#L175 and ff looks to me like an implementation to avoid the above mentioned limitation </p>
<p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">line 177: <br style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: normal;" />
if (thread->handles.count() < MAXIMUM_WAIT_OBJECTS) {
DEBUG() << "Added handle" << handle.handle << "for" << absolutePath << "to watch" << fileInfo.absoluteFilePath() << "to existing thread " << thread;
....
}
line 195:
if (!found) {
QWindowsFileSystemWatcherEngineThread *thread = new QWindowsFileSystemWatcherEngineThread();
DEBUG() << " ###Creating new thread" << thread << "(" << (threads.count()+1) << "threads)";
}</p></pre>
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<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;"><p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">Yep, found the commit that fixed this:</p>
<p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">commit 0c58fe61b18317d071ac27857bd8cf4d52ec6703
Author: dt <a href="mailto:qtc-committer@nokia.com" style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: normal;">qtc-committer@nokia.com</a>
Date: Wed Jul 15 14:23:38 2009 +0200</p>
<p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;"><div class="codehilite" style="background: #f8f8f8"><pre style="line-height: 125%">Support more than <span style="color: #666666">63</span> handles in QWindowsFileSystemWatcher
We spawn<span style="color: #666666">/</span>stop additional threads as needed to watch any number of
files<span style="color: #666666">/</span>directories. The old logic of using just one handle per watched
directory (regardless of how many files we watch in it.) is preserved.
In the worst <span style="color: #008000; font-weight: bold">case</span> a <span style="color: #008000; font-weight: bold">thread</span> is started per <span style="color: #666666">63</span> files to watch.
This enabled Qt Creator to watch all .pro and .pri files even <span style="color: #008000; font-weight: bold">while</span>
having qt<span style="border: 1px solid #FF0000">'</span>s projects.pro and qtcreator.pro open.
Task<span style="color: #666666">-</span>number<span style="color: #666666">:</span> <span style="color: #666666">185259</span>, <span style="color: #666666">253014</span>
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<p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">So actually this works since Qt 4.6.</p></pre>
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<p>- David</p>
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<p>On January 5th, 2015, 6:43 p.m. UTC, Ralf Habacker wrote:</p>
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<div>Review request for KDE Frameworks.</div>
<div>By Ralf Habacker.</div>
<p style="color: grey;"><i>Updated Jan. 5, 2015, 6:43 p.m.</i></p>
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<b style="color: #575012; font-size: 10pt;">Repository: </b>
kcoreaddons
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Description </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">Remove obsolate class KFileSystemWatcher, which is handled by Windows implementation of Qt5 QFileSystemWatcher.</pre>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Diffs</b> </h1>
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<li>src/lib/CMakeLists.txt <span style="color: grey">(b2b46b164097f2394957f99ec4fb97b52f2bbc96)</span></li>
<li>src/lib/io/kdirwatch.cpp <span style="color: grey">(71f1892180b51cf65426696b4ffe918a02debba0)</span></li>
<li>src/lib/io/kdirwatch_p.h <span style="color: grey">(12839fdf4af5312eae3a636cec73f9dd2a41057d)</span></li>
<li>src/lib/io/kdirwatch_win.cpp <span style="color: grey">(846e91ab1c932fbe1117ca6e3de3008f7f3a2130)</span></li>
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<p><a href="https://git.reviewboard.kde.org/r/121861/diff/" style="margin-left: 3em;">View Diff</a></p>
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