# Bug fixes for significant performance impairement in 5.7

**URL:** <https://forums.percona.com/t/bug-fixes-for-significant-performance-impairement-in-5-7/5237>\
**Category:** Percona XtraDB Cluster 5.x\
**Created:** [November 25, 2016, 7:26am UTC](https://forums.percona.com/t/bug-fixes-for-significant-performance-impairement-in-5-7/5237 "2016-11-25T07:26:10Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Abraxas](https://avatars.discourse-cdn.com/v4/letter/a/a87d85/32.png) [@Abraxas](https://forums.percona.com/u/Abraxas)\
**Post date:** [November 25, 2016, 7:26am UTC](https://forums.percona.com/t/bug-fixes-for-significant-performance-impairement-in-5-7/5237/1 "2016-11-25T07:26:10Z")

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Hi,  
After upgrading to XtraDB Cluster 5.7 (from 5.6), we noticed a severe performance decrease for select count(\*) and sum() queries. Turns out there are several bug in 5.7, and some are already fixed.

For example Bug 81854 ([url][MySQL Bugs: #81854: Force index is skipped while executing select count(\*)](https://bugs.mysql.com/bug.php?id=81854%5B/url%5D)) has been fixed for the 5.7.18 release (that will hopefully appear soon).  
Would Percona push these bug soon after being published? With not the newest Percona version is 5.7.14 ☹

Thanks,  
Alex

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**Author:** ![krunalbauskar](https://avatars.discourse-cdn.com/v4/letter/k/439d5e/32.png) [@krunalbauskar](https://forums.percona.com/u/krunalbauskar)\
**Post date:** [November 27, 2016, 10:12pm UTC](https://forums.percona.com/t/bug-fixes-for-significant-performance-impairement-in-5-7/5237/2 "2016-11-27T22:12:41Z")

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Hello Abraxas,

- PXC uses Percona Server as its upstream and so PXC release is only possible after PS is done with said release. (Besides this there is dependency on Codership parts too)  
(So for PXC we release new version once per quarter given the refresh efforts involved unless there is need like security fixes).