On my Exchange 2007 single instance server, there is currently a very high IO Read operation taking place against the database volume and it's during a non maintenance time (middle of the morning). How can I find what task Exchange is doing to read large amounts of data from that volume? The only data that exists on that volume is the MailboxDatabase.edb file.

Than

Hello

tip: try monitor with exmon http://www.microsoft.com/en-gb/download/details.aspx?id=11461

Thank you. I will give this tool a try. I am guessing it had to be either a Maintenance Schedule Task that ran over or the Managed Folder Assistant that was running.

Hi,

According to your description, I understand that Exchange task due to high I/O reading.
If I misunderstand your concern, please do not hesitate to let me know.

I want to double confirm whether this issue arise in Exchange server runtime or intermittent.
Please try to run ExBPA to monitor Exchange health so that you can get more details about your Exchange server.
Besides, I find an article about What Causes Exchange Disk I/O, for your reference:
https://technet.microsoft.com/en-us/library/bb738154(v=exchg.80).aspx

Thanks

It appears that the database is doing the online defrag during this time of high disk IO. I have my maintenance window set for midnight to 4am, but maybe the task continues to run if it was started during that time?

Hi,

It could be happen.
To increase the efficiency of maintenance and backup processes, you may want to schedule your maintenance processes and backup operations to run at different times.
More details about defragment Exchange databases, please refer to: https://support.microsoft.com/en-us/kb/328804?wa=wsignin1.0

Thanks