# Percolation against same non-changed docs? **URL:** \ **Category:** Elasticsearch\ **Created:** [September 12, 2014, 8:26pm UTC](https://discuss.elastic.co/t/percolation-against-same-non-changed-docs/19766 "2014-09-12T20:26:42Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![IronMike](https://avatars.discourse-cdn.com/v4/letter/i/e9a140/32.png) [@IronMike](https://discuss.elastic.co/u/IronMike)\ **Post date:** [September 12, 2014, 8:26pm UTC](https://discuss.elastic.co/t/percolation-against-same-non-changed-docs/19766/1 "2014-09-12T20:26:42Z")
I understand the concept of how docs are checked against existing percolators. One thing I am not clear on, does elasticSearch run against percolators again for same un-changed documents? eg. I just indexed 5 million docs and ran it against all percolators. The next day, I ran the same 5 million docs again, does it check against the percolators again, or is it smart enough to know these are same docs? is percolating done in-memory, so it doesn't take a lot of time to get matches back? Thanks -- 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 [elasticsearch+unsubscribe@googlegroups.com](mailto:elasticsearch+unsubscribe@googlegroups.com). To view this discussion on the web visit [https://groups.google.com/d/msgid/elasticsearch/a0aa904d-c755-4c9e-ae21-fc6d06906e26%40googlegroups.com](https://groups.google.com/d/msgid/elasticsearch/a0aa904d-c755-4c9e-ae21-fc6d06906e26%40googlegroups.com). For more options, visit [https://groups.google.com/d/optout](https://groups.google.com/d/optout). ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [July 6, 2017, 1:02am UTC](https://discuss.elastic.co/t/percolation-against-same-non-changed-docs/19766/2 "2017-07-06T01:02:40Z")