Chapter 6 Configuration Limits for Release 3.4

Configuration limits for Oracle VM represent tested and recommended limits, and are fully supported by Oracle.

Table 6.1 Server Pool and Cluster Maximums

Item

x86 Maximum

SPARC Maximum

Oracle VM Servers in a server pool (unclustered)

64

64

Oracle VM Servers in a server pool (clustered)

32

32

Number of servers

256 (16 servers * 16 server pools)

256 (16 servers * 16 server pools)

Number of server pools

16

16

Number of configured virtual machines

5120 (20 virtual machines * 256 servers)

5120 (20 virtual machines * 256 servers)

Number of running virtual machines

2,560 (10 virtual machines per server * 256 servers)

32768 (128 virtual machines per server * 256 servers)

  • Fujitsu M10-4S, this limitation is 65536 (256 virtual machines per server * 256 servers)

  • Oracle SPARC M-series servers, this limitation is 128 virtual machines per server * the number of physical domains (PDoms). Each physical domain acts as its own server with its own set of logical domains.


Note

Some performance tuning is required in Oracle VM environments where you manage more than 80 instances of Oracle VM Server with a single instance of Oracle VM Manager. In these environments, you should increase JVM memory allocation to 8G and reduce the interval of statistics collection. See the following topics for more information:

Oracle Support can apply additional tuning configurations to optimize Oracle VM Manager performance, such as reducing the number of events that Oracle VM Manager processes. Contact Oracle Support for more information.

Table 6.2 Oracle VM Server Maximums

Item

x86 Maximum

SPARC Maximum

CPUs

288 (Tested)

384 (Designed)

Equivalent to the number of available CPUs.

  • Oracle SPARC M7-16 this is equal to 4096

  • Oracle SPARC M6 this is equal to 3072.

  • Oracle SPARC M5 this is equal to 1536.

  • Oracle SPARC T5 this is equal to 1024.

  • Fujitsu M10 this is equal to 2048 (fully configured).

Virtual CPUs per host

4096

8 per core on Oracle M-series and Oracle T-series

  • Oracle SPARC M5 has 6 cores per socket.

  • Oracle SPARC M6 has 12 cores per socket.

  • Oracle SPARC T5 has 16 cores per socket.

2 per core on Fujitsu M10

  • Fujitsu M10 has 16 cores per socket.

RAM

6 TB

Equivalent to available RAM.

  • 32 TB on a Fujitsu M10, Oracle SPARC M5 or Oracle SPARC M6.

  • 2 TB on an Oracle SPARC T7-4.

  • 8 TB on an Oracle SPARC M7-16.

  • 4 TB on a Oracle SPARC T5.

A small amount of RAM is required for the hypervisor.

Concurrently Running Virtual Machines

1024

The maximum number of concurrently running virtual machines depends on the virtual machine configuration, hardware resources, and workloads the virtual machines are running. For this reason, the practical limit for concurrently running virtual machines is 300.

128 per physical domain (PDOM)

Oracle SPARC M5 or M6 each have a maximum of 512 logical domains (128 logical domains per physical domain * 4 physical domains). However, when following Oracle best practices that allocate full cores for guests, the maximum number of logical domains is 192 on Oracle SPARC M5 and 384 on Oracle SPARC M6.


Table 6.3 Virtual Machine Maximums

Item

x86 Maximum

SPARC Maximum

Virtual CPUs

PVM: 256

HVM: 128

PVHVM: 128; or 32 if using Oracle VM Paravirtual Drivers for Microsoft Windows Release 3.2.3.

Equivalent to the number of available CPUs on the server.

  • Oracle SPARC M7-16 available CPUs is equal to 4096.

  • Oracle SPARC M6 available CPUs is equal to 3072.

  • Fujitsu M10 (fully configured) available CPUs is equal to 2048.

These maximums do not account for CPUs allocated to any other domains, such as the control domain. The hypervisor can allocate subsets of the overall CPU, memory, and I/O resources of a server to any given logical domain.

Virtual RAM on 32-bit guests

PVM: 64 GB

HVM: 64 GB

PVHVM: 64 GB

N/A

Virtual RAM on 64-bit guests

PVM: 500,000 MB

HVM: 1,000,000 MB

Exceeding the 1 TB limit may work, but can result in slow boot times and the possibility that the virtual machine hangs at boot and soft lockups occur on the hosting Oracle VM Server.

If your environment needs to support live migration for HVM guests, this value must not exceed 1 TB.

PVHVM: 2,000,000 MB; or 256 GB if using Oracle VM Paravirtual Drivers for Microsoft Windows Release 3.2.3.

Equivalent to the amount of available RAM installed on the server.

  • 32 TB on a Fujitsu M10, Oracle SPARC M5 or Oracle SPARC M6.

  • 2 TB on an Oracle SPARC T7-4.

  • 8 TB on an Oracle SPARC M7-16.

A small amount of RAM is required for the hypervisor.

These maximums do not account for RAM that is allocated to any other domains, such as the control domain. The hypervisor can allocate subsets of the overall CPU, memory, and I/O resources of a server to a given logical domain.

Virtual NICs

PVM: 31

HVM: 8

PVHVM: 8

The limit to the number of virtual disks and virtual NICs is shared when using the Oracle VM Paravirtual Drivers for Microsoft Windows. Therefore, if you define 8 virtual NICs, only 32 virtual disks can be defined for the same virtual machine.

Depends on the total number of available LDC (logical domains channels).

Total number of virtual NICs and virtual disks per domain for SPARC is no more than the total number of available LDC (logical domains channels) of the supported SPARC server. For more information, see Using Logical Domain Channels in the Oracle VM Server for SPARC Administration Guide.

Virtual disks

Limits provided here are imposed by the guest kernel and not the hypervisor. The maximums presented depend on the capabilities of the guest operating system.

PVM: 104

HVM: 4 IDE (including CD-ROM), 7 SCSI

PVHVM: 107; or 40 if using Oracle VM Paravirtual Drivers for Microsoft Windows Release 3.2.3.

The limit to the number of virtual disks and virtual NICs is shared when using the Oracle VM Paravirtual Drivers for Microsoft Windows. Therefore, if you define 8 virtual NICs, only 32 virtual disks can be defined for the same virtual machine.

Depends on the total number of available LDC (logical domains channels).

Total number of virtual NICs and virtual disks per domain for SPARC is no more than the total number of available LDC (logical domains channels) of the supported SPARC server. For more information, see Using Logical Domain Channels in the Oracle VM Server for SPARC Administration Guide.

Virtual disk size

OCFS2: 64 TB

NFS: 10 TB

Equivalent to the size of available disks on the server.

The Oracle Solaris limit is 263.


Note

Virtual machine maximums assume a single virtual machine using all available resources.

Table 6.4 Storage Maximums

Item

x86 Maximum

SPARC Maximum

LUNs in a storage array

This limit should not be confused with multipath devices. Each identical LUN connected to a single multipath device is considered to be a separate LUN with regard to this limit. For example the following configurations are supported 1,000 LUNs with 2 paths each, 500 LUNs with 4 paths each, 250 LUNs with 8 paths each.

iSCSI: 1000 LUNs and 2000 Paths

Fibre Channel (FC): 1000 LUNs and 4000 Paths

232 targets.

OCFS2 volume size

64 TB

N/A

Files per OCFS2 volume

30,000

N/A


Table 6.5 Network Maximums

Item

x86 Maximum

SPARC Maximum

NICs/ports per network bond

256

255 per bond or aggregate.

Network bonds per Oracle VM Server

No limit

No limit

Number of VLANs

1024

1024

Number of MAC addresses

10240

10240