vCenter Server places limits on the number of simultaneous virtual machine migration and provisioning operations that can occur on each host, network, and datastore.

Note

Simultaneous migrations with vMotion can only occur if the virtual machine is moving between hosts in the same cluster and is not changing its resource pool.

Each operation, such as a migration with vMotion or cloning a virtual machine, is assigned a resource cost. Each type of resource, such as host, datastore, or network, has a maximum cost that it can support at any one time. Any new migration or provisioning operation that would cause a resource to exceed its maximum cost does not proceed immediately, but is queued until other operations complete and release resources. Each of the network, datastore, and host limits must be satisfied in order for the operation to proceed.

Network limits apply to migrations with vMotion only. Network limits depend on both the version of ESXi and the network type.

Network Limits for Migration with vMotion lists network limits for migration with vMotion.

Network Limits for Migration with vMotion

Operation

ESX/ESXi Version

Network Type

Maximum Cost

vMotion

3.x

1GigE and 10GigE

2

vMotion

4.0

1GigE and 10GigE

2

vMotion

4.1, 5.0

1GigE

4

vMotion

4.1, 5.0

10GigE

8

All migrations with vMotion have a network resource cost of 1.

Datastore limits apply to migrations with vMotion and with Storage vMotion. A migration with vMotion involves one access to the datastore. A migration with storage vMotion involves one access to the source datastore and one access to the destination datastore.

Datastore Limits for Migration with vMotion and Storage vMotion lists datastore limits for migration with vMotion and Storage vMotion. Datastore Resource Costs for vMotion and Storage vMotion lists the datastore resource costs for migration with vMotion and Storage vMotion.

Datastore Limits for Migration with vMotion and Storage vMotion

Operation

ESX/ESXi Version

Maximum Cost

vMotion/Storage vMotion

3.x

8

vMotion/Storage vMotion

4.0

8

vMotion/Storage vMotion

4.1, 5.0

128

Datastore Resource Costs for vMotion and Storage vMotion

Operation

ESX/ESXi Version

Datastore Resource Cost

vMotion

3.x

1

vMotion

4.0

1

vMotion

4.1

1

Storage vMotion

3.x

1

Storage vMotion

4.0

1

Storage vMotion

4.1, 5.0

16

Host limits apply to migrations with vMotion, Storage vMotion, and other provisioning operations such as cloning, deployment, and cold migration.

Host Limits for vMotion, Storage vMotion, and Provisioning Operations lists the host limits for migrations with vMotion, migrations with Storage vMotion, and provisioning operations. Host Resource Costs for vMotion, Storage vMotion, and Provisioning Operations lists the host resource cost for these operations.

Host Limits for vMotion, Storage vMotion, and Provisioning Operations

Operation

ESX/ESXi Version

Maximum Cost

vMotion

3.x, 4.0, 4.1, 5.0

2, 2, 8, 8, respectively

Storage vMotion

3.x, 4.0, 4.1, 5.0

2

other provisioning operations

3.x, 4.0, 4.1, 5.0

8

Host Resource Costs for vMotion, Storage vMotion, and Provisioning Operations

Operation

ESX/ESXi Version

Host Resource Cost

vMotion

3.x

4

vMotion

4.0

4

vMotion

4.1, 5.0

1

Storage vMotion

3.x

4

Storage vMotion

4.0

4

Storage vMotion

4.1, 5.0

4

other provisioning operations

3.x, 4.0, 4.1, 5.0

1