Thanks a lot Toki. I will get back to you soon regarding patch update after having discussion with the team.
Thanks & Regards On Fri, Sep 28, 2018 at 11:30 AM Toke Eskildsen <t...@kb.dk> wrote: > RAUNAK AGRAWAL <agrawal.rau...@gmail.com> wrote: > > > curl http://localhost:8983/solr/collection_name/stream -d > > 'expr=facet(collection_name,q="id:953",bucketSorts="week > > desc",buckets="week",bucketSizeLimit=200,sum(sales), > > sum(amount),sum(days))' > > Stats on numeric fields then. > > > Also in my collection, I have almost 10 Billion documents > > with many deletions (close to 40%). > > Quite a lot of documents and in this case deletions counts, as the > internal structures for the deleted documents still needs to be iterated. > In scale this looks somewhat like our 18 billion document setup, with the > addendum that we use quite large segments (900GB). > > The performance regressions we encountered with Solr 7 lead to > https://issues.apache.org/jira/browse/LUCENE-8374 which helped a lot > (performance testing has not finished). If you have or can easily create a > test server where your shard(s) is the same size as your production shards, > I'd be happy to port the patch to Solr 7.2.1 to see it it helps. I am > looking for independent verification, so it is no bother. > > > I was planning to run optimise to merge the segments but > > spoke to admin team and lucidworks guys and they were > > against it saying that it will make very large segment file. > > If your bottleneck is the same as ours, the large segment would mean worse > performance (with Solr 7). > > > Is it true that optimise in solr should not be used, as it comes with > other issues? > > No simple answer there. If you have an index that you update very rarely, > it can save memory and processing power. If you have a live index where you > add and delete documents, it will probably be a bad idea. One strategy used > with time series data is to have old and immutable data in dedicated > collections, which can then be optimized. > > - Toke Eskildsen >