MySQL Bugs: #27068: manual should discourage NTFS compression for large tables

Bug #27068	manual should discourage NTFS compression for large tables
Submitted:	13 Mar 2007 8:08	Modified:	16 Mar 2007 15:38
Reporter:	Shane Bester (Platinum Quality Contributor)	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: Documentation	Severity:	S3 (Non-critical)
Version:	*	OS:	Windows (windows)
Assigned to:	MC Brown	CPU Architecture:	Any
Tags:	compression, ntfs, windows

Description:
During some large myisam tests on windows, the alter table failed with this mysterious error:

070312 16:19:40 [Warning] Warning: Enabling keys got errno 22, retrying

OS error code  22:  Invalid argument

I found out a possible cause for it, was that my --tmpdir pointed to an NTFS folder that was compressed (to save space).  I noticed the tmpfile got to > 30GB before the error occurred.  There was still plenty of free space.

How to repeat:
Read MSDN:

http://msdn2.microsoft.com/en-us/library/aa364219.aspx

[The NTFS File System File Compression]
...
"If you compress a file that is larger than 30 gigabytes, the compression may not succeed."

If you really want a testcase to show the problem, use the one in bug #27029 , but enable folder compression on tmpdir and datadir...

Suggested fix:
This note might be added to the windows installation or troubleshooting section of the manual. NTFS compression should be disabled for mysql datadir and tmpdir directories.

I've added a note to the errors/problems section of the manual highlighting this issue in the discussion of space/disk full errors.