Logical Domains - Supported Hardware

Supported Hardware

The SPARC Hypervisor runs in the Hyper-Privileged execution mode, which was introduced in the sun4v architecture. The sun4v processors released as of December 2012 are the UltraSPARC T1, the T2, T2 Plus, the SPARC T3 and T4; all are used in T-series servers. Systems based on UltraSPARC T1 support only Logical Domains versions 1.0-1.3. The newer types of T-series servers support both older Logical Domains and newer Oracle VM Server for SPARC product version 2.0 and later.

These include the UltraSPARC T1-based:

• Sun / Fujitsu SPARC Enterprise T1000 and T2000 servers
• Sun Fire T1000 and T2000 servers
• Netra T2000 Server
• Netra CP3060 Blade
• Sun Blade T6300 Server Module

UltraSPARC T2-based:

• Sun / Fujitsu SPARC Enterprise T5120 and T5220 servers
• Sun Blade T6320 Server Module
• Netra CP3260 Blade
• Netra T5220 Rackmount Server

UltraSPARC T2 Plus systems:

• Sun / Fujitsu SPARC Enterprise T5140 and T5240 servers (2 sockets)
• Sun Blade T6340 Server Module (2 sockets)
• Sun / Fujitsu SPARC Enterprise T5440 (4 sockets)

SPARC T3 systems :

• Sun / Fujitsu SPARC T3-1 servers (1 socket)
• Sun SPARC T3-1B Server Module (1 socket)
• Sun / Fujitsu SPARC T3-2 servers (2 sockets)
• Sun / Fujitsu SPARC T3-4 servers (4 sockets)

SPARC T4 systems

• SPARC T4-1 Server (1 socket)
• SPARC T4-1B Server Module (blade)
• SPARC T4-2 Server (2 sockets)
• SPARC T4-4 Server (4 sockets)

Technically, the virtualization product consists of two interdependent components: the combination of the hypervisor in the T-series server firmware and the Logical Domains Manager software installed on Solaris operating system running within the control domain (see Logical Domain roles). This dictates the strict requirements for the versions of the software and firmware: each particular version of Logical Domains (Oracle VM Server for SPARC) software requires a certain minimum version of the hypervisor to be installed into the T-series server firmware.

Logical Domains exploits the "Chip Multi Threading" (CMT) nature of the listed CoolThreads processors. A single chip contains up to 16 CPU cores, and each core has either four hardware threads (for the UltraSPARC T1) or eight hardware threads (for the UltraSPARC T2/T2+, and SPARC T3/T4) that act as virtual CPUs. All CPU cores execute instructions concurrently, and each core switches between threads—typically when a thread stalls on a cache miss or goes idle—within a single clock cycle. This lets the processor gain throughput that is lost during cache misses in conventional CPU designs.

Each processor can support as many as one domain per hardware thread — that's up to 32 domains for the UltraSPARC T1, 64 domains for the UltraSPARC T2 and SPARC T4, and 128 domains for UltraSPARC T3 in case of a single-processor server. Servers with 2-4 UltraSPARC T2+ or SPARC T3/T4 CPUs support as many logical domains as the number of processors multiplied by the number of threads of each CPU. Alternatively, and typically, a given domain can be assigned multiple CPU threads for additional capacity within a single OS instance. CPU threads, RAM, and virtual I/O devices can be added to or removed from a domain by administrator issuing command in the control domain. This change takes effect immediately without the need to reboot the affected domain, which can immediately make use of added CPU threads or continue operating with reduced CPU threads.

In case of hypervisor hosts connected to a shared storage (SAN or NAS), running guest domains can be securely live migrated between servers without outage (starting with Oracle VM Server for SPARC version 2.1). The process involves high-speed encryption of VM memory contents before they are transmitted between servers, by cryptographic accelerators available on all processors with sun4v architecture.