# pt-online-schema-change has not optimized my mysql table

**URL:** <https://forums.percona.com/t/pt-online-schema-change-has-not-optimized-my-mysql-table/4717>\
**Category:** Percona Toolkit\
**Created:** [February 12, 2016, 2:27am UTC](https://forums.percona.com/t/pt-online-schema-change-has-not-optimized-my-mysql-table/4717 "2016-02-12T02:27:25Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Abdelbassit](https://avatars.discourse-cdn.com/v4/letter/a/b5ac83/32.png) [@Abdelbassit](https://forums.percona.com/u/Abdelbassit)\
**Post date:** [February 12, 2016, 2:27am UTC](https://forums.percona.com/t/pt-online-schema-change-has-not-optimized-my-mysql-table/4717/1 "2016-02-12T02:27:25Z")

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Hello,

I understand that with that pt-online-schema-change tool you can optimize your mysql table, but I used it with one table after deleting colums from this table, but I don’t won any free space…

The table has 41G space and deleting columns I had calculated gain 11G space, but using this tool I still with 41G…

This is the command that I used:

pt-online-schema-change --alter “ENGINE=InnoDB” D=my\_database,t=mytable --max-lag=30000 Threads\_running=100 --execute

More información:

I’m using Percona-server-5.5

Any suggestion?

Thank you!

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<div class="post-metadata">

**Author:** ![pintu\_ag23](https://avatars.discourse-cdn.com/v4/letter/p/97f17d/32.png) [@pintu\_ag23](https://forums.percona.com/u/pintu_ag23)\
**Post date:** [February 12, 2016, 5:00pm UTC](https://forums.percona.com/t/pt-online-schema-change-has-not-optimized-my-mysql-table/4717/2 "2016-02-12T17:00:29Z")

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did u check the free space from information\_schema.tables table?