documentCache vs IO Cache?
Hi, Apologies if this is a silly question, I just can't find anything explaining the benefits online. Would anyone be able to tell me why you would use a documentCache, if you have sufficient RAM on your machine that the OS disk cache is effectively caching all the documents anyway? Thanks! Unless expressly stated otherwise in this email, this e-mail is sent on behalf of Auto Trader Limited Registered Office: 1 Tony Wilson Place, Manchester, Lancashire, M15 4FN (Registered in England No. 03909628). Auto Trader Limited is part of the Auto Trader Group Plc group. This email and any files transmitted with it are confidential and may be legally privileged, and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the sender. This email message has been swept for the presence of computer viruses.
Re: documentCache vs IO Cache?
On 3/13/2021 11:36 AM, Karl Stoney wrote: Apologies if this is a silly question, I just can't find anything explaining the benefits online. Would anyone be able to tell me why you would use a documentCache, if you have sufficient RAM on your machine that the OS disk cache is effectively caching all the documents anyway? I'm pretty sure that the document cache stores uncompressed data. With the disk cache, the decompression step would be required, using CPU resources and taking a little bit of time. Reading from the document cache would be faster and not hit the CPU as hard. Since I think version 4.1, Solr (Lucene, really) writes stored fields in compressed format. Thanks, Shawn
Re: Conflict between atomic update and highlighting constraints
Good point. Using a different stored field for highlights has been asked for; there's a JIRA issue & a patch: https://issues.apache.org/jira/browse/SOLR-1105 I'm too busy to push this forward by myself but if you can take over there, I can work with you (or anyone) to get it in. ~ David Smiley Apache Lucene/Solr Search Developer http://www.linkedin.com/in/davidwsmiley On Fri, Mar 12, 2021 at 12:32 PM gnandre wrote: > Hi, > > I am running into a conflict between two constraints. > > Atomic updates require copy-field destinations to be stored=false. However, > if we want to use these copy-field destination fields in highlighting then > they need to be stored=true. > > How to resolve this conflict? >
