# How does last\_run work for S3?

**URL:** <https://discuss.elastic.co/t/how-does-last-run-work-for-s3/183617>\
**Category:** Logstash\
**Created:** [May 30, 2019, 9:54pm UTC](https://discuss.elastic.co/t/how-does-last-run-work-for-s3/183617 "2019-05-30T21:54:56Z")\
**Posts on this page:** 1\
**Showing post:** 4

<div class="post-metadata">

**Author:** ![Badger](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/badger/32/25190_2.png) [@Badger](https://discuss.elastic.co/u/Badger)\
**Post date:** [June 1, 2019, 8:38pm UTC](https://discuss.elastic.co/t/how-does-last-run-work-for-s3/183617/4 "2019-06-01T20:38:17Z")

</div>

My understanding is that the s3 input fetches every object from the bucket and compares the last\_modified metadata with the sincedb. If watch\_for\_new\_files is set it will do that over and over, which is why you might want one of the backup options and the delete option so that once an object is processed it is no longer fetched over and over again.

---

_[View the full topic](https://discuss.elastic.co/t/how-does-last-run-work-for-s3/183617)._