+++ This bug was initially created as a clone of Bug #905635 +++

Description of problem:
Default my.cnf doesn't point mysql to use /var/tmp and this caused mysqldump, mysql_upgrade and others to fail on my system.

Version-Release number of selected component (if applicable):
mysql-libs-5.5.29-1.fc18.x86_64

How reproducible:
always, on one of my system

Steps to Reproduce:
1. run mysqldump or mysql_upgrade on a system with a small /tmp on tmpfs
  
Actual results:
Fails with a message containing
 Can't create/write to file '/tmp/#sql_60e_0.MYI' (Errcode: 2) 

Expected results:
  working as before

Additional info:
Googling for the error message shows workaround as adding
  tmpdir=/var/tmp
to the
  [mysqld]
section of
  /etc/my.cnf

--- Additional comment from Tom Lane on 2013-01-29 17:20:28 EST ---

TBH, fixing this in mysql is the Wrong Thing.  F18's choice to put /tmp on tmpfs by default is questionable even on personal/laptop systems, and utterly brain-dead for servers.  I'd recommend turning it off system-wide rather than hacking applications one at a time.  See https://fedoraproject.org/wiki/Features/tmp-on-tmpfs

--- Additional comment from Henrique Martins on 2013-01-29 17:53:39 EST ---

Understood, and I actually already disabled this to take effect as of the next reboot of the machine where I had this problem.

However, as far as I can find with google, it seems that Fedora/FESCO is going to keep this going forward, so someone needs to file bug reports for every single application, for the benefit of people that won't turn it off.

--- Additional comment from Honza Horak on 2013-01-31 09:24:50 EST ---

According to [1] having TMPDIR on tmpfs can cause even bigger troubles in mysql in case of replication slave. If we won't concern a possibility of reverting that F18 feature (I don't believe that happens), I'd vote to change mysql's default to /var/tmp.

Then in case somebody believes /tmp will mean a performance improvement for him and limited space wouldn't be an issue, one can always define tmpdir variable in the my.cnf file. For most of cases /var/tmp should be good enough.

[1] http://dev.mysql.com/doc/refman/5.5/en/server-options.html#option_mysqld_tmpdir

--- Additional comment from Honza Horak on 2013-02-11 09:10:27 EST ---

Created attachment 696099 [details]
Make tmpdir a configurable option

I've sent the attached patch to MySQL and MariaDB upstreams. It adds ability to specify tmpdir using "-DTMPDIR=/var/tmp" during build configuration.

http://bugs.mysql.com/bug.php?id=68338
https://mariadb.atlassian.net/browse/MDEV-4165

--- Additional comment from Fedora Admin XMLRPC Client on 2013-05-09 10:02:59 EDT ---

This package has changed ownership in the Fedora Package Database.  Reassigning to the new owner of this component.