# Upgrade to Percona 5.6.30,something happened

**URL:** <https://forums.percona.com/t/upgrade-to-percona-5-6-30-something-happened/4953>\
**Category:** Percona Server for MySQL 5.6\
**Created:** [July 5, 2016, 9:03pm UTC](https://forums.percona.com/t/upgrade-to-percona-5-6-30-something-happened/4953 "2016-07-05T21:03:10Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![linyue](https://avatars.discourse-cdn.com/v4/letter/l/a3d4f5/32.png) [@linyue](https://forums.percona.com/u/linyue)\
**Post date:** [July 5, 2016, 9:03pm UTC](https://forums.percona.com/t/upgrade-to-percona-5-6-30-something-happened/4953/1 "2016-07-05T21:03:10Z")

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After I upgrade to Percona 5.6.30,my long\_query\_time set 1s, in slow log many “# administrator command: Prepare;” occured , it cost 1-3s . And “SELECT @@session.tx\_isolation;" “SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;” also occur similarly . I want to know why “# administrator command: Prepare;” cost much time ? is it mysql bug ?