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<p class="MsoNormal">Hi Users<o:p></o:p></p>
<p class="MsoNormal">I recently started experimenting with jemalloc and found that jemalloc controls fragmentation phenomenally. A process that was running out of its allocated quota of 2g of virtual memory now uses only 1000mb of virtual memory and works without
any crashes. I am trying to incorporate this library but it seems people have some apprehensions about it associated with big data applications(enhanced by facebook).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Can someone answer the following question, while I am trying to do some code reading:-<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">1.<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Does jemalloc waste memory at the cost of speed and is optimized for big data applications ?<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">2.<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Are there scenarios where if many threads are competing for malloc, it will dynamically create new arenas to reduce thread contention and are their parameters to control/tune them ?<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">3.<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Are there any other tunable parameters I should look at to ensure jemalloc doesn’t uncontrollably allocate memory in stress scenarios to optimize performance at the cost of memory . In my environment, I would expect jemalloc to reduce
performance rather than allocate more memory/arenas/pools to better performance.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Any help is appreciated while I ramp up on this new magical library.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">-Mayank<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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