Yeah that's what I was suggesting in my response too. I don't think your load balancer should be doing this but whatever script does the release (restarting the container) should do this so that when the ping is enabled the warming has finished.
On Sat, Nov 10, 2012 at 3:33 PM, Erick Erickson <erickerick...@gmail.com>wrote: > Hmmm, rather than hit the ping query, why not just send in a real query and > only let the queued ones through after the response? > > Just a random thought > Erick > > > On Sat, Nov 10, 2012 at 2:53 PM, Amit Nithian <anith...@gmail.com> wrote: > > > Yes but the problem is that if user facing queries are hitting a server > > that is warming up and isn't being serviced quickly, then you could > > potentially bring down your site if all the front end threads are blocked > > on Solr queries b/c those queries are waiting (presumably at the > container > > level since the filter hasn't finished its init() sequence) for the > warming > > to complete (this is especially notorious when your front end is rails). > > This is why your ping to enable/disable a server from the load balancer > has > > to be accurate with regards to whether or not a server is truly ready and > > warm. > > > > I think what I am gathering from this discussion is that the server is > > warming up, the ping is going through and tells the load balancer this > > server is ready, user queries are hitting this server and are queued > > waiting for the firstSearcher to finish (say these initial user queries > are > > to respond in 500-1000ms) that's terrible for performance. > > > > Alternatively, if you have a bunch of servers behind a load balancer, you > > want this one server (or block of servers depending on your deployment) > to > > be reasonably sure that user queries will return in a decent time > (whatever > > you define decent to be) hence why this matters. > > > > Let me know if I am missing anything. > > > > Thanks > > Amit > > > > > > On Sat, Nov 10, 2012 at 10:03 AM, Erick Erickson < > erickerick...@gmail.com > > >wrote: > > > > > Why does it matter? The whole idea of firstSearcher queries is to warm > up > > > your system as fast as possible. The theory is that upon restarting the > > > server, let's bet this stuff going immediately... They were never > > intended > > > (as far as I know) to complete before any queries were handled. As an > > > aside, I'm not quite sure I understand why pings during the warmup are > a > > > problem. > > > > > > But anyway. firstSearcher is particularly relevant because the > > > autowarmCount settings on your caches are irrelevant when starting the > > > server, there's no history to autowarm.... > > > > > > But, there's no good reason _not_ to let queries through while > > > firstSearcher is doing it's tricks, they just get into the queue and > are > > > served as quickly as they may. That might be some time since, as you > say, > > > they may not get serviced until the expensive parts get filled. But I > > don't > > > think having them be serviced is doing any harm. > > > > > > Now, newSearcher and autowarming of the caches is a completely > different > > > beast since having the old searchers continue serving requests until > the > > > warmups _does_ directly impact the user, they don't see random slowness > > > because a searcher is being opened. > > > > > > So I guess my real question is whether you're seeing a measurable > problem > > > or if this is a red herring.... > > > > > > FWIW, > > > Erick > > > > > > > > > On Thu, Nov 8, 2012 at 2:54 PM, Aaron Daubman <daub...@gmail.com> > wrote: > > > > > > > Greetings, > > > > > > > > I have several custom QueryComponents that have high one-time startup > > > costs > > > > (hashing things in the index, caching things from a RDBMS, etc...) > > > > > > > > Is there a way to prevent solr from accepting connections before all > > > > QueryComponents are "ready"? > > > > > > > > Especially, since many of our instance are load-balanced (and > > > > added-in/removed automatically based on admin/ping responses) > > preventing > > > > ping from answering prior to all custom QueryComponents being ready > > would > > > > be ideal... > > > > > > > > Thanks, > > > > Aaron > > > > > > > > > >
