In this case, I have >400 million documents, so I understand it taking a while.
That said, I'm still not sure I understand why it would take *more* time. In your example above, wouldn't it have to create an 11.92MB bitset even if I *don't* cache the bitset? It seems the mere act of storing the work after it's done (it has to be done in either case) is taking 4 whole seconds? On Tue, Jun 3, 2014 at 3:59 PM, Shawn Heisey <s...@elyograg.org> wrote: > On 6/3/2014 2:44 PM, Brett Hoerner wrote: > > If I run a query like this, > > > > fq=text:lol > > fq=created_at_tdid:[1400544000 TO 1400630400] > > > > It takes about 6 seconds. Following queries take only 50ms or less, as > > expected because my fqs are cached. > > > > However, if I change the query to not cache my big range query: > > > > fq=text:lol > > fq={!cache=false}created_at_tdid:[1400544000 TO 1400630400] > > > > It takes 2 seconds every time, which is a much better experience for my > > "first query for that range." > > > > What's odd to me is that I would expect both of these (first) queries to > > have to do the same amount of work, expect the first one stuffs the > > resulting bitset into a map at the end... which seems to have a 4 second > > overhead? > > > > Here's my filterCache from solrconfig: > > > > <filterCache class="solr.FastLRUCache" > > size="64" > > initialSize="64" > > autowarmCount="32"/> > > I think that probably depends on how many documents you have in the > single index/shard. If you have one hundred million documents stored in > the Lucene index, then each filter entry is 12500000 bytes (11.92MB) in > size - it is a bitset representing every document and whether it is > included or excluded. That data would need to be gathered and copied > into the cache. I suspect that it's the gathering that takes the most > time ... several megabytes of memory is not very much for a modern > processor to copy. > > As for how long this takes, I actually have no idea. You have two > filters here, so it would need to do everything twice. > > Thanks, > Shawn > >