Operating system error number 995 (windows aio) - innodb crashing

[Dave Clayton]

Hi all,

Our website has experienced steady growth over the past couple of years, and recently we've been having problems with MySQL - 3 crashes in the past couple of months or so. The error log states:

090212 22:43:05 InnoDB: Operating system error number 995 in a file operation.
InnoDB: Some operating system error numbers are described at
InnoDB: http://dev.mysql.com/doc/refman/5.0/en/operating-system-error-codes.html
InnoDB: File name C:\mysql\data\ibdata1
InnoDB: File operation call: 'Windows aio'.
InnoDB: Cannot continue operation.

This seems to require a manual restart of the MySQL service then waiting for it to restore from the binary log.

The only thing I can think that might be causing it is I tweaked some of the config settings, including increasing innodb_buffer_pool_size to 1GB - the server has 2GB of RAM on Windows Server 03 - then today trawling the bugs db I found that someone mentioned if the buffer pool is too high it can cause excessive paging. So, I've reduced it back to 512MB for now, hoping that this will restore stability. One other thing to note is we also run a mail server on the same box which does experience moderate - high traffic - we recently tried disabling all logging for this service to try and reduce the number of file handles in use - but that was after the last crash so doesn't seem to have helped.

If anyone has any suggestions on this issue I'd really appreciate it!

Thanks for reading.