You can create virtual disks on which to store your database's data and log files to improve performance. You can in turn create these virtual disks on datastores optimized for I/O performance, redundancy, or disk usage depending on the type of data you want to store on them.

Data Director allows you to define virtual disks to which you can map your DBVM's operating system and database, data, log, and backup disks. You can then map the virtual disks to different datastores using disk provisioning and storage allocations that you specify to improve disk usage, performance, and redundancy. For example, you can create dedicated datastores to service I/O intensive database workloads.

As you create DBVMs, DB templates, and databases you have the opportunity to define the storage structure and disk layout that best suits your database deployment's workloads and use cases. The parameters described below are the configuration options you specify to create a disk layout to use with the databases you provision using Data Director. Before you begin creating DBVMs and DB templates, consider the storage capacity and I/O requirements of the databases you intend to provision using Data Director.

Disk Type

When you create a base DB template you can specify which disks to use for data files, and which to use for log files. If you are creating a database for use in production environments you should place data and log files on separate virtual disks so that when the database is performing inserts, updates, and deletes, and both the data and log files are being written to at the same time, you can avoid I/O performance degradation. The virtual disks you specify can in turn be assigned to datastores with appropriate storage capacity and I/O performance for the types of applications and workloads the database will support.

Path

You must specify the path (or location) of the virtual disks you want to assign for each disk type. The path is the mount point for Linux, or the volume name for Windows.

When specifying a virtual disk path for the Windows operating system, the drive letters C: through H: are reserved for use by the base DBVM. You can use the drive letters I: or above to specify volumes for use as data or log disks.

Note

You must provide a mount point or volume name that does not already exist. If you specify a duplicate mount point that is already in use, Data Director will return the error message Internal address cannot be duplicated or empty when you attempt to convert the DBVM to a DB template.

Virtual Disk Provisioning Types

Data Director supports the following disk provisioning profiles:

Eager Zeroed Thick Provision

A type of thick virtual disk that supports clustering features such as Fault Tolerance. Space required for the virtual disk is allocated at creation time. In contrast to the flat format, the data remaining on the physical device is zeroed out when the virtual disk is created. Eager Zeroed Thick Provision disks provide superior performance for applications supporting I/O intensive operations.

Thin Provision

Use this format to save storage space. For the thin disk, you provision as much datastore space as the disk would require based on the value that you enter for the disk size. However, the thin disk starts small and at first, uses only as much datastore space as the disk needs for its initial operations.

If the thin disk needs additional space, it can grow to its maximum capacity and occupy the entire datastore space provisioned to it. Also, you can manually convert the thin disk into a thick disk.

Minimum Storage Size

You can specify a minimum storage size to use for each disk that you create. Carefully consider how much storage space you have available, and how much you will need for your data and log usage.

Note

Determining log disk storage requirements depends upon several factors. Refer to your database vendors documentation for information on log storage capacity planning for your particular database.

Minimum Storage Size for Data Disks

Database

Minimum Size of Data Disk

MySQL

1 GB

Oracle

2 GB

SQL Server

1 GB

vPostgres

1 GB