I've tested with the Direct docValuesFormat which is uncompressed in-memory. But I haven't seen any noticeable performance gain. I've been meaning to dig into exactly why I wasn't seeing a performance gain, but haven't had the chance to do this yet.
If you test out the Direct docValuesFormant, I'd be interested in hearing your findings. Joel Bernstein http://joelsolr.blogspot.com/ On Wed, Jun 22, 2016 at 5:37 AM, Aashish Dattani <aash...@zettata.com> wrote: > Hi everyone, > > I have 2 million documents in my Solr index. I have enabled docValues on > one > of the integer fields, and set its docValuesFormat to Memory. This is > because I want to have very quick forward lookups on this field in my > custom > component. > > I am running my Solr installation on a 35GB RAM machine, so memory is not a > big resource constraint. > > I was expecting that making the docValuesFormat to Memory will make the > docValues access to be as fast as a simple array lookup - but it didn't. > Upon digging deeper and inspecting the MemoryDocValuesProducer class, it > seems like Lucene is doing a delta compression and storing it in a > PackedInts datastructure, which is making the lookups slower. > > Is there any configuration/implementation that I can use to make sure that > the docValues are faster than they are right now - essentially any way to > ensure that it is stored as an in-memory array? Do you see any downsides to > using this approach? > > I'd appreciate any help on this. > > Thanks! > > > > -- > View this message in context: > http://lucene.472066.n3.nabble.com/In-memory-docValues-speedup-tp4283783.html > Sent from the Solr - User mailing list archive at Nabble.com. >
