Hello! On Wed, Apr 16, 2014 at 08:38:10PM +1000, SplitIce wrote:
> Hi all, > > I have spent the day troubleshooting why one server in our network reloaded > / tested configuration extremely slowly. > > We have found that server_names scales very poorly, once a certain point is > reached (approx 5.5k entries globally, 5k entries for a single host) > performance drops from a <0.5s reload time to 15s+. > > The large host of ~5,000 entries is a malware domain zone and all server > names in this zone are using the wildcard name format. > > For now we have resolved this issue by fixing an inefficiency in our > configuration (namely using *.domain.com and domain.com) however I feel > this is most likely a bug or at-least an unintended behaviour. > > Relevant configuration entries: > server_names_hash_max_size 8000; > server_names_hash_bucket_size 128; With max_size 8000, and 5k entries - probability of collisions while building a cache is high (think of birthday paradox). And bucket_size 128 isn't high enough to allow multiple collisions. As a result, nginx may (and likely will) spend a lot of time trying to build an optimal hash. Trivial solution is to use higher max_size and/or bucket_size. -- Maxim Dounin http://nginx.org/ _______________________________________________ nginx mailing list nginx@nginx.org http://mailman.nginx.org/mailman/listinfo/nginx
