On Tue, Apr 22, 2014 at 02:40:08PM -0700, Shawn Zhou wrote: > > > Our performance tests show that ISC BIND (authoritative only setup) doesn't > perform well on RHEL 6.4 in comparison with FreeBSD 7: bind_perf.png > > bind_perf.png > Shared with Dropbox > View on www.dropbox.com Preview by Yahoo > > The "Drop Rate" is the ratio of the amount response never received and the > amount of requests were sent. BIND is configured with 24 worker threads and > 24 UPD listener, same as the CPU threads we have. BIND process already has > '-20' nice priority set on RHEL and '20' on the FreeBSD host.The test hosts > running RHEL 6.4 and FreeBSD 7 are identical in term of hardware: > 2 x Xeon E5-2430, 24GB DDR3 RAM, 1Gb/s NIC. > > We conducted the tests by having our load generators re-play BIND query logs > using our custom scripts and send the queries to the test server at a given > rate, say, 200,00 query per seconds. The queries are preloaded into the > memory so that's no overhead for our load generators to read queries from > disk while sending test queries. > > What we've observed that socket receiving queue (Recv-Q from netstat) drained > very fast on FreeBSD but got back up pretty fast on RHEL 6 when we ramped up > the test traffic. With net.core.rmem_default set to 40MB, it only helps RHEL > to be able to handle 180,000qps before we start to see receive buffer > overruns again and drop rate increases linearly.
If packet drop happens in the host kernel you can easily check where this happens: dropwatch -l kas start Would be nice to know. Greetings, Hannes _______________________________________________ dns-operations mailing list [email protected] https://lists.dns-oarc.net/mailman/listinfo/dns-operations dns-jobs mailing list https://lists.dns-oarc.net/mailman/listinfo/dns-jobs
