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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">The concept of memory pool cache is different from the CPU architecture cache.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Unlike some DSP, in the modern CPU and system, it is not a common use case to assign addresses to the cache and lock them as a memory. In especial, the data buffer is too large.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">The memory pool cache is a LIFO to store the pointers and trying to reduce the memory footprints and reduce the CPU cache conflict and eviction. (Always try to use the used
memory previously)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Only when trying to access the memory itself, a whole cache line will be checked and try to be loaded. It is impossible that a CPU load a whole buffer (2KB for example) directly
without any READ / WRITE / FLUSH to the cache.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Comic Sans MS"">BR. Bing<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-ligatures:none">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-ligatures:none"> lonc0002@yahoo.com <lonc0002@yahoo.com>
<br>
<b>Sent:</b> Thursday, April 25, 2024 12:24 AM<br>
<b>To:</b> users@dpdk.org<br>
<b>Subject:</b> question about MemPool<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b><span style="font-size:7.5pt;font-family:"Verdana",sans-serif;color:black;mso-ligatures:none">External email: Use caution opening links or attachments</span></b><span style="font-size:7.5pt;font-family:"Verdana",sans-serif;color:black;mso-ligatures:none">
</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-ligatures:none"><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-ligatures:none"><o:p> </o:p></span></p>
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<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">When doing a rte_mempool_get_bulk() with a cache enabled mempool, first objects are retrieved from cache and then from the common pool which I assume is sitting in shared memory (DDR or L3?). Wouldn’t accessing the objects from the mempool
in shared memory itself pull those objects into processor cache? Can this be avoided?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<br>
Vince<o:p></o:p></p>
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