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<div class="elementToProof"><span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);" class="elementToProof"><span class="x_elementToProof FluidPluginCopy"><span class="x_elementToProof x_ContentPasted1 ContentPasted1" style="font-size:12pt;color:rgb(0, 0, 0) !important;background-color:rgb(255, 255, 255) !important">This
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<pre class="x_FluidPluginCopy x_ContentPasted2 x_elementToProof ContentPasted1">> You do:
> converted.intoMemorySegment(MemorySegment.ofArray(control), offset, ByteOrder.nativeOrder());
>
> Can you just do:
>
> converted.intoArray(control, offset);
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<div class="elementToProof"><span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);" class="elementToProof"><span class="x_elementToProof FluidPluginCopy"><span class="x_elementToProof x_ContentPasted1 ContentPasted1" style="font-size:12pt;color:rgb(0, 0, 0) !important;background-color:rgb(255, 255, 255) !important">I
did so because I found that Vector<Byte> actually does not have that method. After your suggestion, I switched to use ByteVector instead by Vector<Byte>. Surprisingly, this time the hashmap delivers</span></span> a better performance. It 2~3 times faster during
the insertion procedure. However, there was still a performance gap behind the standard hashmap during finding precedure.<br>
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For the ease of discussion, I attach the relevant code here:<br>
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<pre class="ContentPasted2 elementToProof"><span style="color:#cc7832" class="ContentPasted2">private int </span><span style="color:#ffc66d" class="ContentPasted2">findWithHash</span>(<span style="color:#cc7832" class="ContentPasted2">long </span>hash<span style="color:#cc7832" class="ContentPasted2">, </span><span style="color:#507874" class="ContentPasted2">K </span>key) {<br class="ContentPasted2"> <span style="color:#cc7832" class="ContentPasted2">byte </span>h2 = Util.<span style="font-style:italic" class="ContentPasted2">h2</span>(hash)<span style="color:#cc7832" class="ContentPasted2">; </span><span style="color:#808080" class="ContentPasted2">//highest 7 bits<br class="ContentPasted2"></span><span style="color:#808080" class="ContentPasted2"> </span><span style="color:#cc7832" class="ContentPasted2">int </span>position = Util.<span style="font-style:italic" class="ContentPasted2">h1</span>(hash) & <span style="color:#9876aa" class="ContentPasted2">bucketMask</span><span style="color:#cc7832" class="ContentPasted2">; </span><span style="color:#808080" class="ContentPasted2">// h1 is just long to int<br class="ContentPasted2"></span><span style="color:#808080" class="ContentPasted2"> </span><span style="color:#cc7832" class="ContentPasted2">int </span>stride = <span style="color:#6897bb" class="ContentPasted2">0</span><span style="color:#cc7832" class="ContentPasted2">;<br class="ContentPasted2"></span><span style="color:#cc7832" class="ContentPasted2"> while </span>(<span style="color:#cc7832" class="ContentPasted2">true</span>) {<br class="ContentPasted2"> <span style="color:#cc7832" class="ContentPasted2">var </span>mask = matchByte(position<span style="color:#cc7832" class="ContentPasted2">, </span>h2).toLong()<span style="color:#cc7832" class="ContentPasted2">; </span><span style="color:#808080" class="ContentPasted2">// match byte is to load a vector of byte and do equality comparison<br class="ContentPasted2"></span><span style="color:#808080" class="ContentPasted2"> </span><span style="color:#cc7832" class="ContentPasted2">while </span>(MaskIterator.<span style="font-style:italic" class="ContentPasted2">hasNext</span>(mask)) { <br class="ContentPasted2"> <span style="color:#cc7832" class="ContentPasted2">var </span>bit = MaskIterator.<span style="font-style:italic" class="ContentPasted2">getNext</span>(mask)<span style="color:#cc7832" class="ContentPasted2">;<br class="ContentPasted2"></span><span style="color:#cc7832" class="ContentPasted2"> </span>mask = MaskIterator.<span style="font-style:italic" class="ContentPasted2">moveNext</span>(mask)<span style="color:#cc7832" class="ContentPasted2">;<br class="ContentPasted2"></span><span style="color:#cc7832" class="ContentPasted2"> var </span>index = (position + bit) & <span style="color:#9876aa" class="ContentPasted2">bucketMask</span><span style="color:#cc7832" class="ContentPasted2">;<br class="ContentPasted2"></span><span style="color:#cc7832" class="ContentPasted2"> if </span>(key.equals(<span style="color:#9876aa" class="ContentPasted2">keys</span>[index])) <span style="color:#cc7832" class="ContentPasted2">return </span>index<span style="color:#cc7832" class="ContentPasted2">;<br class="ContentPasted2"></span><span style="color:#cc7832" class="ContentPasted2"> </span>}<br class="ContentPasted2"><br class="ContentPasted2"> <span style="color:#cc7832" class="ContentPasted2">if </span>(matchEmpty(position).anyTrue()) {<br class="ContentPasted2"> <span style="color:#cc7832" class="ContentPasted2">return </span>-<span style="color:#6897bb" class="ContentPasted2">1</span><span style="color:#cc7832" class="ContentPasted2">;<br class="ContentPasted2"></span><span style="color:#cc7832" class="ContentPasted2"> </span>}<br class="ContentPasted2"><br class="ContentPasted2"> stride += <span style="color:#9876aa;font-style:italic" class="ContentPasted2">VECTOR_LENGTH</span><span style="color:#cc7832" class="ContentPasted2">;<br class="ContentPasted2"></span><span style="color:#cc7832" class="ContentPasted2"> </span>position = (position + stride) & <span style="color:#9876aa" class="ContentPasted2">bucketMask</span><span style="color:#cc7832" class="ContentPasted2">;<br class="ContentPasted2"></span><span style="color:#cc7832" class="ContentPasted2"> </span>}<br class="ContentPasted2">}</pre>
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>From Intellij IDEA's profiler, it seems that a large portion of time is spent on building the vectormask. I see there is an underlying bTest operation converting the results to boolean array and then give the mask. Will this be internally optimized to a single
movemask operation by JVM?<br>
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