# What happens inside index.blocks? **URL:** \ **Category:** Elasticsearch\ **Created:** [October 2, 2012, 7:52am UTC](https://discuss.elastic.co/t/what-happens-inside-index-blocks/9208 "2012-10-02T07:52:02Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Andrej](https://avatars.discourse-cdn.com/v4/letter/a/d9b06d/32.png) [@Andrej](https://discuss.elastic.co/u/Andrej)\ **Post date:** [October 2, 2012, 7:52am UTC](https://discuss.elastic.co/t/what-happens-inside-index-blocks/9208/1 "2012-10-02T07:52:02Z")
Hi, I was wondering if someone could give me an inside view on whats happening when I set index.blocks.write or index.blocks.read to true. Are writing/reading threads stopped, should I gain search/indexing performance? Is refreshing disabled when blocks.write is set? Or am I just safe that those operations are not performed? Thanks! Andrej -- ---
**Author:** ![BillyEm](https://avatars.discourse-cdn.com/v4/letter/b/c4cdca/32.png) [@BillyEm](https://discuss.elastic.co/u/BillyEm)\ **Post date:** [October 4, 2012, 12:22am UTC](https://discuss.elastic.co/t/what-happens-inside-index-blocks/9208/2 "2012-10-04T00:22:44Z")
Have you checked the index writer in Lucene 3.5.x? Since Lucene is now transacted it is possible for an operation to have a reference (or links to a reference). While other blocks are being committed and becoming ver+1. What to do to preserve currency with the beginning of the operation? Block a read on transacted write operations, or block a write on transacted Read operations. Once the operation completes the block/lock/synchronization is released and the waiting (if set so) read or write can proceed. whaddya think? Is that it? It should be very tightly scoped in the ES codebase and easy to find? On Tuesday, October 2, 2012 3:52:02 AM UTC-4, Andrej Rosenheinrich wrote: > Hi, > > I was wondering if someone could give me an inside view on whats happening > when I set index.blocks.write or index.blocks.read to true. Are > writing/reading threads stopped, should I gain search/indexing performance? > Is refreshing disabled when blocks.write is set? Or am I just safe that > those operations are not performed? > > Thanks! > Andrej -- ---
**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, 3:10am UTC](https://discuss.elastic.co/t/what-happens-inside-index-blocks/9208/3 "2017-07-06T03:10:15Z")