# 1 index 10 shards vs 10 indexes 1 shard (performance point of view)

**URL:** <https://discuss.elastic.co/t/1-index-10-shards-vs-10-indexes-1-shard-performance-point-of-view/8330>\
**Category:** Elasticsearch\
**Created:** [July 5, 2012, 4:38pm UTC](https://discuss.elastic.co/t/1-index-10-shards-vs-10-indexes-1-shard-performance-point-of-view/8330 "2012-07-05T16:38:30Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Thibaut\_Britz](https://avatars.discourse-cdn.com/v4/letter/t/a6a055/32.png) [@Thibaut\_Britz](https://discuss.elastic.co/u/Thibaut_Britz)\
**Post date:** [July 5, 2012, 4:38pm UTC](https://discuss.elastic.co/t/1-index-10-shards-vs-10-indexes-1-shard-performance-point-of-view/8330/1 "2012-07-05T16:38:30Z")

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Hi,

Is there a performance difference between querying 10 indexes with 1  
shard, or 1 index with 10 shards?  
How is the merging of the results be performed: Multithreaded in both  
cases? Are there any low level differences when executing a search  
between both cases, which could impact the speed?

Thanks,  
Thibaut

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**Author:** ![kimchy](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/kimchy/32/44952_2.png) [@kimchy](https://discuss.elastic.co/u/kimchy)\
**Post date:** [July 5, 2012, 10:44pm UTC](https://discuss.elastic.co/t/1-index-10-shards-vs-10-indexes-1-shard-performance-point-of-view/8330/2 "2012-07-05T22:44:00Z")

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Searching on 1 index with 10 shards or 10 indices with 1 shard has exactly  
the same cost. At the end, a search is broken down and executed on each  
shard it corresponds to (on different threads / nodes), and merged.

On Thu, Jul 5, 2012 at 6:38 PM, Thibaut Britz \<[thibaut.britz@trendiction.com](mailto:thibaut.britz@trendiction.com)

> wrote:

> Hi,
> 
> Is there a performance difference between querying 10 indexes with 1  
> shard, or 1 index with 10 shards?  
> How is the merging of the results be performed: Multithreaded in both  
> cases? Are there any low level differences when executing a search  
> between both cases, which could impact the speed?
> 
> Thanks,  
> Thibaut

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**Author:** ![Thibaut\_Britz](https://avatars.discourse-cdn.com/v4/letter/t/a6a055/32.png) [@Thibaut\_Britz](https://discuss.elastic.co/u/Thibaut_Britz)\
**Post date:** [July 6, 2012, 7:46am UTC](https://discuss.elastic.co/t/1-index-10-shards-vs-10-indexes-1-shard-performance-point-of-view/8330/3 "2012-07-06T07:46:52Z")

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Thanks!

On Fri, Jul 6, 2012 at 12:44 AM, Shay Banon [kimchy@gmail.com](mailto:kimchy@gmail.com) wrote:

> Searching on 1 index with 10 shards or 10 indices with 1 shard has exactly  
> the same cost. At the end, a search is broken down and executed on each  
> shard it corresponds to (on different threads / nodes), and merged.
> 
> On Thu, Jul 5, 2012 at 6:38 PM, Thibaut Britz  
> [thibaut.britz@trendiction.com](mailto:thibaut.britz@trendiction.com) wrote:
> 
> > Hi,
> > 
> > Is there a performance difference between querying 10 indexes with 1  
> > shard, or 1 index with 10 shards?  
> > How is the merging of the results be performed: Multithreaded in both  
> > cases? Are there any low level differences when executing a search  
> > between both cases, which could impact the speed?
> > 
> > Thanks,  
> > Thibaut

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**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, 3:21am UTC](https://discuss.elastic.co/t/1-index-10-shards-vs-10-indexes-1-shard-performance-point-of-view/8330/4 "2017-07-06T03:21:19Z")

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