<table><tr><td style="">bruns added a comment.
</td><a style="text-decoration: none; padding: 4px 8px; margin: 0 8px 8px; float: right; color: #464C5C; font-weight: bold; border-radius: 3px; background-color: #F7F7F9; background-image: linear-gradient(to bottom,#fff,#f1f0f1); display: inline-block; border: 1px solid rgba(71,87,120,.2);" href="https://phabricator.kde.org/D22333">View Revision</a></tr></table><br /><div><div><blockquote style="border-left: 3px solid #8C98B8;
color: #6B748C;
font-style: italic;
margin: 4px 0 12px 0;
padding: 8px 12px;
background-color: #F8F9FC;">
<div style="font-style: normal;
padding-bottom: 4px;">In <a href="https://phabricator.kde.org/D22333#494384" style="background-color: #e7e7e7;
border-color: #e7e7e7;
border-radius: 3px;
padding: 0 4px;
font-weight: bold;
color: black;text-decoration: none;">D22333#494384</a>, <a href="https://phabricator.kde.org/p/apol/" style="
border-color: #f1f7ff;
color: #19558d;
background-color: #f1f7ff;
border: 1px solid transparent;
border-radius: 3px;
font-weight: bold;
padding: 0 4px;">@apol</a> wrote:</div>
<div style="margin: 0;
padding: 0;
border: 0;
color: rgb(107, 116, 140);"><blockquote style="border-left: 3px solid #8C98B8;
color: #6B748C;
font-style: italic;
margin: 4px 0 12px 0;
padding: 8px 12px;
background-color: #F8F9FC;">
<div style="font-style: normal;
padding-bottom: 4px;">In <a href="https://phabricator.kde.org/D22333#494253" style="background-color: #e7e7e7;
border-color: #e7e7e7;
border-radius: 3px;
padding: 0 4px;
font-weight: bold;
color: black;text-decoration: none;">D22333#494253</a>, <a href="https://phabricator.kde.org/p/bruns/" style="
border-color: #f1f7ff;
color: #19558d;
background-color: #f1f7ff;
border: 1px solid transparent;
border-radius: 3px;
font-weight: bold;
padding: 0 4px;">@bruns</a> wrote:</div>
<div style="margin: 0;
padding: 0;
border: 0;
color: rgb(107, 116, 140);"><blockquote style="border-left: 3px solid #8C98B8;
color: #6B748C;
font-style: italic;
margin: 4px 0 12px 0;
padding: 8px 12px;
background-color: #F8F9FC;">
<div style="font-style: normal;
padding-bottom: 4px;">In <a href="https://phabricator.kde.org/D22333#494152" style="background-color: #e7e7e7;
border-color: #e7e7e7;
border-radius: 3px;
padding: 0 4px;
font-weight: bold;
color: black;text-decoration: none;">D22333#494152</a>, <a href="https://phabricator.kde.org/p/apol/" style="
border-color: #f1f7ff;
color: #19558d;
background-color: #f1f7ff;
border: 1px solid transparent;
border-radius: 3px;
font-weight: bold;
padding: 0 4px;">@apol</a> wrote:</div>
<div style="margin: 0;
padding: 0;
border: 0;
color: rgb(107, 116, 140);"><blockquote style="border-left: 3px solid #8C98B8;
color: #6B748C;
font-style: italic;
margin: 4px 0 12px 0;
padding: 8px 12px;
background-color: #F8F9FC;">
<div style="font-style: normal;
padding-bottom: 4px;">In <a href="https://phabricator.kde.org/D22333#494146" style="background-color: #e7e7e7;
border-color: #e7e7e7;
border-radius: 3px;
padding: 0 4px;
font-weight: bold;
color: black;text-decoration: none;">D22333#494146</a>, <a href="https://phabricator.kde.org/p/bruns/" style="
border-color: #f1f7ff;
color: #19558d;
background-color: #f1f7ff;
border: 1px solid transparent;
border-radius: 3px;
font-weight: bold;
padding: 0 4px;">@bruns</a> wrote:</div>
<div style="margin: 0;
padding: 0;
border: 0;
color: rgb(107, 116, 140);"><p>Why not just a singleshot timer from the constructor? Avoids any initial blocking ...</p></div>
</blockquote>
<p>Initial, but doesn't fix the problem. We could potentially delay this few seconds instead, but we'd still be getting an odd ~500ms freeze randomly<br />
Or we can just decide to move blocking or heavy algorithms to separate threads and enjoy our multicore computers and a fluid experience.</p></div>
</blockquote>
<p>Where does the blocking happen? How do you guarantee none of the later call block? Large parts of the code are executed in the main thread anyway, only the initial list creation happens in a worker thread.</p></div>
</blockquote>
<p>listFromQuery is the big blocking call we are moving into a separate thread.</p></div>
</blockquote>
<p>Again, where is it blocking? Which backend?</p>
<blockquote style="border-left: 3px solid #a7b5bf; color: #464c5c; font-style: italic; margin: 4px 0 12px 0; padding: 4px 12px; background-color: #f8f9fc;"><blockquote style="border-left: 3px solid #a7b5bf; color: #464c5c; font-style: italic; margin: 4px 0 12px 0; padding: 4px 12px; background-color: #f8f9fc;"><p>Also, if this is a generic problem, why only fix it in the dataengines, not in Solid itself?</p></blockquote>
<p>This would mean refactoring how Solid works and even coming up with entirely new concepts. I don't discard doing it at some point but I don't think plasmashell startup blockage is reason enough to redo a framework that has been working for about 5 years as is.</p></blockquote>
<p>listFromQuery can be replaced by an asynchronous "enumerate(predicate)" call which uses the existing DeviceAdded signal. This would also remove the inherent race between the listFromQuery and DeviceAdded/DeviceRemoved.</p></div></div><br /><div><strong>REPOSITORY</strong><div><div>R120 Plasma Workspace</div></div></div><br /><div><strong>REVISION DETAIL</strong><div><a href="https://phabricator.kde.org/D22333">https://phabricator.kde.org/D22333</a></div></div><br /><div><strong>To: </strong>apol, Plasma, davidedmundson, bruns<br /><strong>Cc: </strong>bruns, plasma-devel, LeGast00n, jraleigh, fbampaloukas, GB_2, ragreen, Pitel, ZrenBot, himcesjf, lesliezhai, ali-mohamed, jensreuterberg, abetts, sebas, apol, mart<br /></div>