# VACUUM - performance improvement is huge **URL:** https://forum.duplicati.com/t/vacuum-performance-improvement-is-huge/5186 **Category:** Developer **Created:** [November 4, 2018, 11:25am UTC](https://forum.duplicati.com/t/vacuum-performance-improvement-is-huge/5186 "2018-11-04T11:25:26Z") **Posts on this page:** 1 **Showing post:** 28
### Author: ![ts678](https://forum.duplicati.com/letter_avatar_proxy/v4/letter/t/8491ac/32.png) [@ts678](https://forum.duplicati.com/u/ts678) #### Post date: [November 24, 2018, 10:07pm UTC](https://forum.duplicati.com/t/vacuum-performance-improvement-is-huge/5186/28 "2018-11-24T22:07:11Z")
> [@tacioandrade](#): > > Could it be that it was caused by VACCUM right in the database without using Duplicati? If you’re saying there’s a chance you ran it outside of Duplicati while Duplicati might have been at work such as doing a backup, then possibly you got into the access conflict I’d worried about, with stale data put back. Maybe there was even a problem on the data copy to a temporary file, if it could change while it was being copied. This is a deeper SQLite question than I can answer, on exactly how SQLite vacuum is implemented. The test from @mr-flibble seems different from what I think you described, but it does answer how one can get into that unfortunate state with the database. I had hoped SQLite would be able to resist such problems. There’s currently such an error [here](https://forum.duplicati.com/t/duplicati-no-longer-launching-on-mac-database-version/2987/18), so if anyone is good at fixing these, please stop by to help with that… --- _[View the full topic](https://forum.duplicati.com/t/vacuum-performance-improvement-is-huge/5186)._