The sun4v (UltraSPARC-T1) code was removed from -HEAD in May 2011 in (see below). The reason was due to lack of stability somewhere in the VM system, combined with lack of interest from other developers once the initial developer ceased working on it. Because of the latter, the codebase was not keeping up with changes in -HEAD, leading to bitrot.

As of mid-2015 there has been some interest on the mailing lists in picking up sun4v.

The two main difficulties will be:

• getting the existing code back in sync with all the SVN changes to the source tree in the years since the removal
• finishing the existing code

The removal happened in SVN commit 221870 on 20150514.

The version of param.h just previous to the removal was 900037 on 20110513. param.h was not incremented as of the removal.

The last time that the code was built as part of make universe is not yet known, but it is safe to assume that it was some time before the param.h commit.

(below here are the notes from the original developer)

UltraSPARC-T1 support is functionally complete.

Recent changes:

• tod support added
• dynamic hash resizing
• dynamic tsb resizing
• fix TSO and PCIe support for em on sparc
• cddl licensed hypervisor interface code removed and replaced with bsd licensed versions
• “shutdown -r” and “shutdown -h” now work correctly
• loadable modules now work on large memory systems
• fixups for unaligned loads/stores now work

Current work item:

• Virtual network driver - LDC and mdesc support are in

There are a number of known issues that need to be fixed before release:

• serial port not currently supported

The following is a list of items that I would like to see done by the time 7.0 is released.

Longer-term work for logical domaining support:

• virtual disk driver
• CPU hotplug
• memory hotplug - longer term issue, will not happen by 7.0

Desired platform-specific optimizations / features:

• balance interrupts between cpus
• MSI
• profiling
• dynamic TSB resizing - (not yet enabled)
• superpage support
• optimized copyin/copyout
• optimized bzero / bcopy in libc
• T2 10GigE support

Desired platform-independent optimizations:

• reduce coverage of vm page queue mutex
• remove sched_lock

Nice to have functionality:

• minidumps
• java support