maria-discuss team mailing list archive

[Jeremy Cole <jeremycole@xxxxxxxxxx>]

Hello,

Since I was the author of the bug this addressed, MySQL Bug 69477
<http://bugs.mysql.com/bug.php?id=69477> I could comment here.

The InnoDB redo log (innodb_log_file_size) needs to be at least 10x larger
than the largest single BLOB value you intend to store, not larger than the
sum of BLOB data. If you are seeing this error with a log file size of 128
MB, that implies that you have some BLOB column containing at least 12.8
MB. Is that the case? Your use is probably quite strange if your total data
size is only 129 MB and you have BLOBs of that size, but be aware: this bug
fix was for a very serious bug. With the previous behavior usage of such
large BLOBs could result in silent and unrecoverable data loss after a
crash due to overwriting the most recent checkpoint with oversized BLOB
data.

My understanding is that the bug was addressed in 5.7 without introducing a
limitation.

Regards,

Jeremy

On Tue, Jan 20, 2015 at 1:22 AM, Reindl Harald <h.reindl@xxxxxxxxxxxxx>
wrote:

> WTF: "the innodb_log_file_size setting should be 10 times larger than the
> largest BLOB data size found in the rows of your tables" - how is that
> maintainable for a sysadmin?
>
> the whole (file_per_table) database folder is 129 MB,
> innodb_log_file_sizeis 128 MB and nobody can seriously explain me that i
> need a innodb_log_file_size with magnitudes of the whole datasize
>
> Am 20.01.2015 um 03:04 schrieb Jean Weisbuch:
>
>  It seems that the limitation has been introduced on MySQL 5.6.20 :
>> http://dev.mysql.com/doc/relnotes/mysql/5.6/en/news-5-6-20.html
>>
>> Le 20/01/2015 01:03, Reindl Harald a écrit :
>>
>>> InnoDB: The total blob data length (13476124) is greater than 10% of
>>> the redo log file size (5120). Please increase innodb_log_file_size
>>>
>>
>
> _______________________________________________
> Mailing list: https://launchpad.net/~maria-discuss
> Post to     : maria-discuss@xxxxxxxxxxxxxxxxxxx
> Unsubscribe : https://launchpad.net/~maria-discuss
> More help   : https://help.launchpad.net/ListHelp
>
>