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Talk: planning slides (cont..)

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Fischlurch 2026-08-09 05:39:17 +02:00
parent 15090bd997
commit 3f61b106cc
1 changed files with 212 additions and 7 deletions
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FrOSCon26/FrOSCon.26.mm
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@ -240,9 +240,7 @@
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<font NAME="SansSerif" SIZE="21"/>
<node CREATED="1786235664313" ID="ID_1678569803" MODIFIED="1786235696451" TEXT="what is &#xbb;fast&#xab; and what &#xbb;slow&#xab; &#x27f9; Time-Scales"/>
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<node CREATED="1785540830071" ID="ID_126092826" MODIFIED="1785540836160" TEXT="architectural challenge">
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@ -323,7 +321,29 @@
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<node COLOR="#5b280f" CREATED="1785705991375" ID="ID_347714238" MODIFIED="1786245015452" TEXT="visibility?? &#x27f9; NUMA !!">
<icon BUILTIN="button_cancel"/>
<node BACKGROUND_COLOR="#accdc3" COLOR="#3f4015" CREATED="1786245032571" ID="ID_1765938120" MODIFIED="1786245043602" STYLE="fork" TEXT="NUMA schie&#xdf;t hier &#xfc;ber das Ziehl hinaus">
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<richcontent TYPE="NOTE"><html>
<head>
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<p>
allein der Umstand da&#223; Cores direkt an einem Cache h&#228;ngen, gen&#252;gt, um die Notwendigkeit der Synchronisation aufzuzeigen ... daher ist das Schl&#252;sselwort auch &quot;cache-coherence&quot;
</p>
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<node CREATED="1786245489365" ID="ID_763564504" MODIFIED="1786245499980" TEXT="Englisch: coherence, nicht coherency">
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<node CREATED="1786245028814" ID="ID_1433367293" MODIFIED="1786245029751" TEXT="visibility?? &#x27f9; cache-coherency !!"/>
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</node>
<node CREATED="1785706316326" ID="ID_38548076" MODIFIED="1785706326849" TEXT="to ensure both sides see the memory effects">
@ -428,6 +448,9 @@
</node>
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<node BACKGROUND_COLOR="#c8c0b6" COLOR="#690f14" CREATED="1786157164429" HGAP="525" ID="ID_487001972" MODIFIED="1786246634044" TEXT="X" VSHIFT="-18">
<font NAME="SansSerif" SIZE="21"/>
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<node CREATED="1785875859594" ID="ID_404844187" MODIFIED="1785875865559" TEXT="Example: Video Player">
<node CREATED="1785875876826" ID="ID_256659487" MODIFIED="1785875895788" TEXT="have a fast Open-GL pipeline &#x27f9; just need hand-over"/>
<node CREATED="1785875964166" ID="ID_684645417" MODIFIED="1785875979393" TEXT="Backpressure &#x27f8; use fixed-size ring"/>
@ -680,9 +703,65 @@
<node CREATED="1785877094220" ID="ID_1651644833" MODIFIED="1785877434241" TEXT="Diagramm &quot;Application setup&quot;"/>
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<icon BUILTIN="flag-yellow"/>
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<head>
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<body>
<p http-equiv="content-type" content="text/html; charset=utf-8" class="font-claude-response-body break-words whitespace-normal" dir="ltr">
<u>Producer</u>:
</p>
<p http-equiv="content-type" content="text/html; charset=utf-8" class="font-claude-response-body break-words whitespace-normal" dir="ltr">
</p>
<p http-equiv="content-type" content="text/html; charset=utf-8" class="font-claude-response-body break-words whitespace-normal" dir="ltr">
<font face="Monospaced" size="2" color="#261b52">write payload[...]&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;// ordinary stores </font>
</p>
<p http-equiv="content-type" content="text/html; charset=utf-8" class="font-claude-response-body break-words whitespace-normal" dir="ltr">
<font face="Monospaced" size="2" color="#261b52">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;// StoreStore + LoadStore barrier here </font>
</p>
<p http-equiv="content-type" content="text/html; charset=utf-8" class="font-claude-response-body break-words whitespace-normal" dir="ltr">
<font face="Monospaced" size="2" color="#261b52">store(flag, READY, release) </font>
</p>
<p http-equiv="content-type" content="text/html; charset=utf-8" class="font-claude-response-body break-words whitespace-normal" dir="ltr">
</p>
<p http-equiv="content-type" content="text/html; charset=utf-8" class="font-claude-response-body break-words whitespace-normal" dir="ltr">
</p>
<p http-equiv="content-type" content="text/html; charset=utf-8" class="font-claude-response-body break-words whitespace-normal" dir="ltr">
<u>Consumer</u>:
</p>
<p http-equiv="content-type" content="text/html; charset=utf-8" class="font-claude-response-body break-words whitespace-normal" dir="ltr">
</p>
<p http-equiv="content-type" content="text/html; charset=utf-8" class="font-claude-response-body break-words whitespace-normal" dir="ltr">
<font face="Monospaced" size="2" color="#261b52">v = load(flag, acquire) </font>
</p>
<p http-equiv="content-type" content="text/html; charset=utf-8" class="font-claude-response-body break-words whitespace-normal" dir="ltr">
<font face="Monospaced" size="2" color="#261b52">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;// LoadLoad + LoadStore barrier here </font>
</p>
<p http-equiv="content-type" content="text/html; charset=utf-8" class="font-claude-response-body break-words whitespace-normal" dir="ltr">
<font face="Monospaced" size="2" color="#261b52">if (v == READY) </font>
</p>
<p http-equiv="content-type" content="text/html; charset=utf-8" class="font-claude-response-body break-words whitespace-normal" dir="ltr">
<font face="Monospaced" size="2" color="#261b52">&#160;&#160;&#160;&#160;read payload[...]&#160;&#160;&#160;&#160;&#160;// ordinary loads </font>
</p>
<p http-equiv="content-type" content="text/html; charset=utf-8" class="font-claude-response-body break-words whitespace-normal" dir="ltr">
<font face="Monospaced" size="2" color="#261b52">else </font>
</p>
<p http-equiv="content-type" content="text/html; charset=utf-8" class="font-claude-response-body break-words whitespace-normal" dir="ltr">
<font face="Monospaced" size="2" color="#261b52">&#160;&#160;&#160;&#160;// walk away &#8212; no information gained, positive or negative </font>
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<node CREATED="1753974744448" ID="ID_233051154" MODIFIED="1753974749608" TEXT="Demo code"/>
@ -795,7 +874,7 @@
<node CREATED="1786158112260" ID="ID_1719290378" MODIFIED="1786158117815" TEXT="video pushes the limits"/>
<node CREATED="1786158120997" ID="ID_1802759909" MODIFIED="1786158140188" TEXT="&#x27f9; make optimum use of resources"/>
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<node CREATED="1786158146164" ID="ID_1965918049" MODIFIED="1786235987151" TEXT="I/O is &#xbb;problematic&#xab;">
<node CREATED="1786158231476" ID="ID_310766175" MODIFIED="1786158242607" TEXT="much more complex than the &quot;compute&quot; resource"/>
<node CREATED="1786158247058" ID="ID_405882035" MODIFIED="1786158266443" TEXT="it is slow">
<node CREATED="1786158272327" ID="ID_1400639102" MODIFIED="1786158291344" TEXT="slow can refer to..."/>
@ -810,7 +889,7 @@
</node>
<node CREATED="1786158328007" ID="ID_457446692" MODIFIED="1786158570391" TEXT="&#x27f9; it is hard to predict"/>
<node CREATED="1786158352524" ID="ID_1145344027" MODIFIED="1786158354567" TEXT="and especially for Video &#x27f6; a new twist.... "/>
<node CREATED="1786158361606" ID="ID_986117401" MODIFIED="1786158372785" TEXT="IO is no longer slow">
<node CREATED="1786158361606" ID="ID_986117401" MODIFIED="1786235991899" TEXT="I/O is no longer slow">
<node CREATED="1786158373937" ID="ID_947160129" MODIFIED="1786158378724" TEXT="and that&apos;s the problem"/>
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<node CREATED="1786158641707" ID="ID_1475320779" MODIFIED="1786158678740" TEXT="what is &#xbb;fast&#xab; ... and &#xbb;slow&#xab;?"/>
@ -825,6 +904,124 @@
<node CREATED="1786209276951" ID="ID_1586351838" MODIFIED="1786209300679" TEXT="1 clock-cylce &#x2254; 1sec"/>
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<node CREATED="1786236083238" ID="ID_1030610372" MODIFIED="1786236095616" TEXT="I/O just happens"/>
<node CREATED="1786236097484" ID="ID_343037218" MODIFIED="1786236110925" TEXT="handling creates accidental overhead"/>
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<node CREATED="1786236117616" ID="ID_960264533" MODIFIED="1786236129403" TEXT="Solution patterns">
<node CREATED="1785601495587" ID="ID_1049863439" MODIFIED="1786236168822" TEXT="block in processing"/>
<node CREATED="1785601569001" ID="ID_250647320" MODIFIED="1785601575268" TEXT="avoid the blocking"/>
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<node CREATED="1786236228043" ID="ID_59513152" MODIFIED="1786236238313" TEXT="Excourse: Berkely vs. MIT">
<node CREATED="1786236251057" ID="ID_995829099" MODIFIED="1786236253406" TEXT="Berkely">
<node CREATED="1786236321789" ID="ID_1752234528" MODIFIED="1786236351802" TEXT="prefer simple code"/>
<node CREATED="1786236331604" ID="ID_1695326473" MODIFIED="1786236337591" TEXT="ship early"/>
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<node CREATED="1786236372934" ID="ID_768441053" MODIFIED="1786236387905" TEXT="prefer simple interface"/>
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<node CREATED="1786236989681" ID="ID_1900578005" MODIFIED="1786237025505" TEXT="a pair of ringbuffers">
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<head>
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<u>Ringbuffer</u>:<br />
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<p>
<font face="Monospaced" color="#704545">buffer[cursor % RING_SIZE]</font>
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</html></richcontent>
</node>
<node CREATED="1786242211296" ID="ID_1804746347" MODIFIED="1786242216162" TEXT="Kleinvieh...."/>
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<node CREATED="1786242230765" ID="ID_120169631" MODIFIED="1786242235257" TEXT="a queue for Completions"/>
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<node CREATED="1786242318954" ID="ID_893637645" MODIFIED="1786242359199" TEXT="entries tagged with user data item"/>
<node CREATED="1786242363635" ID="ID_1548043873" MODIFIED="1786242386764" TEXT="submissions model classical syscalls"/>
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<node CREATED="1786242404480" ID="ID_387275241" MODIFIED="1786242408617" TEXT="what we got....">
<node CREATED="1786242410435" ID="ID_673729734" MODIFIED="1786242417320" TEXT="making syscalls without making syscalls"/>
<node CREATED="1786242418928" ID="ID_66154275" MODIFIED="1786242428469" TEXT="this started a security nightmare..."/>
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<node CREATED="1786242489571" ID="ID_312711315" MODIFIED="1786242495102" TEXT="liburing">
<node CREATED="1786242497913" ID="ID_231424686" MODIFIED="1786242502130" TEXT="thin abstraction layer"/>
<node CREATED="1786242503167" ID="ID_90257215" MODIFIED="1786242511283" TEXT="programmer friendly interface">
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<node CREATED="1786246153449" MODIFIED="1786246153449" TEXT="StoreStore"/>
<node CREATED="1786246164738" MODIFIED="1786246164738" TEXT="LoadLoad"/>
<node CREATED="1786246177165" MODIFIED="1786246177165" TEXT="LoadStore"/>
<node CREATED="1786246190951" MODIFIED="1786246190951" TEXT="StoreLoad"/>
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<node CREATED="1786246217323" ID="ID_1893817108" MODIFIED="1786246222075" TEXT="Memory Order">
<node CREATED="1786246223006" ID="ID_1140165000" MODIFIED="1786246224709" TEXT="relaxed"/>
<node CREATED="1786246225377" ID="ID_165584437" MODIFIED="1786246249330" TEXT="acquire"/>
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<node CREATED="1786246068359" ID="ID_1757141587" MODIFIED="1786246072948" TEXT="walk away...">
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</node>
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<node CREATED="1786246546790" ID="ID_1627212633" MODIFIED="1786246561350" TEXT="no &#x27f9; immeditately return"/>
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<node CREATED="1786246572246" ID="ID_1144371495" MODIFIED="1786246584476" TEXT="wakeup: signal threads put to sleep on Futex"/>
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<node CREATED="1754271624646" ID="ID_52826289" MODIFIED="1754271626857" TEXT="Grafik">
@ -922,6 +1119,14 @@
<icon BUILTIN="flag-yellow"/>
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</node>
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<icon BUILTIN="pencil"/>
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<icon BUILTIN="wizard"/>
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<node BACKGROUND_COLOR="#d2beaf" COLOR="#5c4d6e" CREATED="1785877291601" ID="ID_517600933" MODIFIED="1785877301089" TEXT="Diagramm &quot;State-Ring&quot;">
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<node BACKGROUND_COLOR="#accdc3" COLOR="#3f4015" CREATED="1785877302464" ID="ID_1725774104" MODIFIED="1785880120631" STYLE="fork" TEXT="Ein Schema ist nebenbei im Chat mit Claude &quot;angefallen&quot;">