Hi All, I had a followup question. I am assuming there can be only one backend instance per thread. Can you please confirm that? So, basically if there are 8 threads of execution, can I assume that there are only 8 backend instances running?
Thanks, Seema On 11/8/13 1:03 PM, "Aki Tuomi" <[email protected]> wrote: >On Fri, Nov 08, 2013 at 07:22:40AM +0000, Seema Datar wrote: >> Hi All, >> >> Does anybody have more information on this? >> >> Thanks, >> Seema >> >> Hi All, >> >> 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 - >> >> 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. >> >> The questions I had are - >> >> >> 1. What is the lifetime of a backend thread? >> 2. How often does a thread get destroyed and a new thread get >>created? >> 3. Is there any interface available to do a cleanup before the >>thread ends? >> >> Thanks, >> Seema > >Lifetime of a backend thread is dependant on several factors, and the only >thing you can assume is that it's not something you can rely on. > >The only thing backend module can use for cleanup is the destructror of >the >backend class. > >Or if you use remote/pipebackend, you can wire it to look for EOF or >signal >and cleanup when either one is received before dying out. > >Aki Tuomi _______________________________________________ Pdns-dev mailing list [email protected] http://mailman.powerdns.com/mailman/listinfo/pdns-dev
