Hi Ron, The cause of this issue is that Elasticsearch uses Lucene's internal doc IDs as tie-breakers. Internal doc IDs might be completely different across replicas of the same data, so this explains why documents that have the same sort values are not consistently ordered.
There are 2 potential ways to fix that problem: 1. Use scroll as David mentionned. It will create a context around your request and will make sure that the same shards will be used for all pages. However, it also gives another warranty, which is that the same point-in-time view on the index will be used for each page, and this is expensive to maintain. 2. Use a custom string value as a preference in order to always hit the same shards for a given session[1]. This will help with always hitting the same shards likely to 1. but without adding the additional cost of a scroll. [1] http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/search-request-preference.html On Mon, Aug 18, 2014 at 8:02 AM, Ron Sher <[email protected]> wrote: > Hi, > > We've noticed a strange behavior in elasticsearch during paging. > > In one case we use a paging size of 60 and we have 63 documents. So the > first page is using size 60 and offset 0. The second page is using size 60 > and offset 60. What we see is that the result is inconsistent. Meaning, > on the 2nd page, we sometimes get results that were before in the 1st page. > > The query we use has an order by some numberic field that has many > documents with the same value (0). > It looks like the ordering between documents according to the same value, > which is 0, isn't consistent. > > Did anyone encounter such behavior? Any suggestions on resolving this? > > We're using version 1.3.1. > > Thanks, > Ron > > -- > You received this message because you are subscribed to the Google Groups > "elasticsearch" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/elasticsearch/CAKHuyJpcYKepYzh%2BBU2MSD2RQ19zjHYiXgf3anWBL9esq9fkGQ%40mail.gmail.com > <https://groups.google.com/d/msgid/elasticsearch/CAKHuyJpcYKepYzh%2BBU2MSD2RQ19zjHYiXgf3anWBL9esq9fkGQ%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > -- Adrien Grand -- You received this message because you are subscribed to the Google Groups "elasticsearch" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/elasticsearch/CAL6Z4j7FJofXSpDjHnpMVs1poHFREbrQ9DPnPX4YnjFjUKg_ng%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
