* General Execution-driven Multiprocessor Simulator (GEMS) Release 2.0
  http://www.cs.wisc.edu/gems/

In 2005, the Wisconsin Multifacet Project released our General
Execution-driven Multiprocessor Simulator (GEMS). GEMS is a set of
modules for Virtutech Simics that enables detailed simulation of
multiprocessor systems, including Chip-Multiprocessors (CMPs). Already,
GEMS has been downloaded by over 750 users and been used in 19 papers
from outside Wisconsin (http://www.cs.wisc.edu/gems/publications.html).

In October 2007, the GEMS team has put its finishing touches on the new
2.0 release, and it is now available for download at:

      http://www.cs.wisc.edu/gems/download.html

Notable features of this release include:

(1) Non-LogTM specific features/updates:
  - x86 support for Ruby (Thanks Soohong Kim for the patch)
  - Simultaneous multi-threading (SMT) support in Opal
  - Protocol fixes
  - Bash scripts to automate generation of "naked/OS/whatever"
checkpoints*

(2) LogTM-specific features/updates:
  - single-chip transactional CMP directory protocol, with sticky-M &
sticky-S directory states
  - support for partial rollback, closed and open nesting
  - support for compensating and commit actions through our software
handler
  - "Perfect" Signature support (can emulate infinite RW bits)
              and Finite Signature support (Bit-Select & H3)
  - Summary signature support (Perfect & finite)
  - Limited LogTM-SE virtualization support, all in simulator**
  - support for ISCA '07 Pathologies systems:
        Eager conflict detection, Lazy version management
        Lazy conflict detection, Lazy version management
        Eager conflict detection, Eager version management, with &
without store-set prediction
        Hybrid conflict resolution policy
  - Sample transactional micro-benchmarks

Please note that the prior SMP LogTM protocol using RW bits is no
longer supported in this release.  Finite RW bit (LogTM-like)
functionality can be emulated by using "Perfect" signatures & the
released CMP protocol.

(3) Future plans include enhanced interconnection network support from
Li-Shiuan Peh's groups at Princeton University.

Footnotes:

*  = Full support for building apache, zeus, and jbb workload
checkpoints should be expected in a patch released shortly.

** =  We plan on integrating more stable support with OpenSolaris in the
future.