Exchange 2010: The mailbox database cache

What is the mailbox database cache?

The database cache stores a subset of the mailbox database in the main memory of the mailbox server. This has the advantage that frequently used data does not have to be read again and again from the relatively slow hard disks of the servers, but instead comes from the fast main memory. Furthermore, this reduces the I/O processes on the hard disks.

Memory requirements for the database cache

ESE requires a guaranteed minimum amount of RAM on the mailbox servers for the database cache. How much RAM is required depends on the number of databases

How large is the database cache on a mailbox server?

How can I change the size of the database cache?

Adjusting the size of the cache can be useful if other services besides Exchange are running on the server (fax solution, etc.)The size of the database cache can be changed using ADSIedit.

First, a connection to the "Configuration" naming context is established

Then navigate to the following entry

Right-click on "CN=InformationStore" to open the context menu and select "Properties". Now search for the values for "msExchESEParamCacheSizeMax" and "msExchESEParamCacheSizeMin"

The values for the maximum and minimum database cache can now be specified here. The values must be specified here in 32 KB pages and not simply as MB or GB.

Example:

The cache should be at least 2 GB in size: 2 GB = 2048000 KB / 32 KB = 64000

For "msExchESEParamCacheSizeMin", 64000 must therefore be entered.

The cache should have a maximum size of 4 GB: 4 GB = 4096000 KB / 32 KB = 128000

Therefore, 128000 must be entered for "msExchESEParamCacheSizeMax".

Finally, the "Microsoft Exchange Information Store" service must be restarted.