pt-online-schema-change Segmentation Fault

[Dave Gregg]

pt-online-schema-change Segmentation Fault

Attempting to run the following....
I have a Master and 2 Slaves
Master IP = 192.168.192.166
I have DSNs setup in the percona.dsns table.

pt-online-schema-change h=192.168.192.166,D=menagerie,t=MyGuests,u=root,p=Kionix --check-interval=5 --max-lag=60 --alter "alter table menagerie.MyGuests modify email varchar(200);" --execute

If I run in "Dry-Run" Mode - everything seems ok.
If I run in Debug...I am not seeing anything jump out at me...
And If I try to execute....this is what i get.

Found 2 slaves:
  Slave9vm
  Slave10vm
Will check slave lag on:
  Slave9vm
  Slave10vm
Operation, tries, wait:
  copy_rows, 10, 0.25
  create_triggers, 10, 1
  drop_triggers, 10, 1
  swap_tables, 10, 1
  update_foreign_keys, 10, 1
Altering `menagerie`.`MyGuests`...
Creating new table...
Created new table menagerie._MyGuests_new OK.
Altering new table...
2015-05-21T15:46:42 Dropping new table...
2015-05-21T15:46:42 Dropped new table OK.
`menagerie`.`MyGuests` was not altered.
Segmentation fault

[Dave Gregg (dgregg)]

Attached a Debug version of:
PTDEBUG=1 pt-online-schema-change h=192.168.192.166,D=menagerie,t=MyGuests,u=root,p=Kionix --check-interval=2 --max-lag=60 --alter "alter table menagerie.MyGuests modify email varchar(200);" --execute > Daves_Percona.log 2>&1

[Dave Gregg (dgregg)]

I was wrong - Even in a Dry-Run I get a Segmentation Fault !!

[Frank Cizmich (frank-cizmich)]

Hello Dave,

There are two issues here.

First:
The --alter option must not include the "ALTER TABLE <table>" part. Change that to: --alter="modify email varchar(200)"

Second:
There is a known and nasty bug that causes the segmentation fault when the alter fails.
https://bugs.launchpad.net/percona-toolkit/+bug/1446928

This is already fixed and will be included in the next release, but a patch is available in the first comment of the issue report in the above link.

I'll include it in this comment for your convenience.

I'll mark this report as a duplicate of the previous one to avoid confusion.

Regards!