On Thu, Jun 23, 2016 at 01:56:59PM -0400, Hui Kang wrote: > > Hi, > In our scalability test for OVN, we observed an in-scalable behaviour of > the > ovn-northd process: the time binding a logical port increases as # of large > port increasing, regardless of whether logical ports belong to the same > logical > switch. The most suspicious function in causing this issue is build_ports() > called by ovnnb_db_run() [1], as described below. > > Test description: > step 1: Create 6 logical switches. For each logical switch, create 200 > logical ports. > step 2: Bind 200 lports from each logical switch on an OVN chassis. > > Test results for step 2: > > # of ports | # of ovn_ports | Cpu cycle spent in | > | allocated in build_port() | built_port(), in million | > 200 | 200 | 25 | > 400 | 400 | 50 | > 600 | 600 | 75 | > 800 | 800 | 93 | > 1000 | 1000 | 108 | > 1200 | 1200 | 125 |
I'm surprised that this is expensive for so few ports. I believe that build_ports() runs in O(n) time where n is the larger of the number of ports in the northbound and southbound databases. Does anyone see anything that would cause quadratic or more regressive behavior there? _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
