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<div>Hi All,</div>
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<div>Does anybody have more information on this?</div>
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<div>Thanks,</div>
<div>Seema</div>
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<span style="font-weight:bold">From: </span>Seema Datar <<a href="mailto:sdatar@yahoo-inc.com">sdatar@yahoo-inc.com</a>><br>
<span style="font-weight:bold">Date: </span>Thursday, November 7, 2013 10:49 AM<br>
<span style="font-weight:bold">To: </span>"<a href="mailto:pdns-users@mailman.powerdns.com">pdns-users@mailman.powerdns.com</a>" <<a href="mailto:pdns-users@mailman.powerdns.com">pdns-users@mailman.powerdns.com</a>>, "<a href="mailto:pdns-dev@mailman.powerdns.com">pdns-dev@mailman.powerdns.com</a>"
<<a href="mailto:pdns-dev@mailman.powerdns.com">pdns-dev@mailman.powerdns.com</a>><br>
<span style="font-weight:bold">Subject: </span>Question regarding life time of backend threads in PDNS<br>
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Hi All,</div>
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We have a use case where we use PDNS with 8 backend threads. We needed to save thread specific data in an mmap. However, I came across the following in PDNS documentation - </div>
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<span style="font-family: 'luxi sans', sans-serif; font-size: medium; text-align: -webkit-left; "><i>PowerDNS may instantiate multiple instances of your backend, or destroy existing copies and instantiate new ones. Backend code should therefore be thread-safe
with respect to its static data. Additionally, it is wise if instantiation is a fast operation, with the possible exception of the first construction.</i></span></div>
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<div><font face="Helvetica">The questions I had are - </font></div>
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<li><font face="Helvetica">What is the lifetime of a backend thread?</font></li><li><font face="Helvetica">How often does a thread get destroyed and a new thread get created?</font></li><li><font face="Helvetica">Is there any interface available to do a cleanup before the thread ends?</font></li></ol>
<div><font face="Helvetica">Thanks,</font></div>
<div><font face="Helvetica">Seema</font></div>
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