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I am using amazon rds mysql 5.6 master instance and 4 slaves. there is big table with 800 GIB size that i want to drop it for releasing space. But when i execute drop command, the server entering to "freeze mode" and cant execute any kind of commands.

similar issue : https://bugs.mysql.com/bug.php?id=44757

I need to remove it from production rds.

  • there is no transactions on this table
  • innodb_file_per_table = ON

I though about Deleting rows in chunks for not create big lag for slaves and then (optional optimize) drop the table.

  • What if you TRUNCATE TABLE first? – Michael - sqlbot Nov 4 '18 at 17:42
  • i tried , the server stacking . becouse of the high amount of data – Stas Rozen Nov 6 '18 at 14:53
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What exact version?

DELETE on a huge table will take a huge amount of time because it is building an "undo" log in case of a crash. Don't use that technique.

What was the value of innodb_file_per_table when the table was built?

  • If OFF (or 0), the table is in ibdata1, which will not shrink and return space to the OS. It will only free up blocks for subsequent use.
  • If ON (or 1), then DROP TABLE will be much faster, but still not instantaneous.
  • If you have FOREIGN KEYs connecting the table (in either direction), well, let's see them. (SHOW CREATE TABLE)

If you need to delete a big part of a table, here are several techniques. This discusses how to do the delete in chunks, and takes Replication issues into account.

  • Hey , MySQL 5.6.39 , innodb_file_per_table = 1 when table created , it dont have any foreign keys . already checked this one mysql.rjweb.org/doc.php/deletebig – Stas Rozen Nov 6 '18 at 14:57
  • Alas, I am town to "clutching at straws". RDS has a bunch of different things going on in the OS; the only "big" step in DROP TABLE (when file_per_table) is actual releasing of all the blocks to the OS. So, I guess this is an RDS problem. (I know MySQL, but not RDS.) – Rick James Nov 6 '18 at 15:24

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