but in case you want a few %% of extra emulation performance - it is still possible to disable it with configure option.
most guests I saw do not use it !
for CPU emulation performance reasons, the alignment check compilation
still can be enabled using configure option --enable-alignment-check.
There is no software in the world which enable #AC exception checking, this
x86 feature is completely legacy but its emulation support costs up to 3-5%
emulation speed.
The checking for #AC exception enable still will be done, if
CPL == 3, EFLAGS.AC = 1 and CR0.AM = 1
but the alignment check is not compiled in, the Bochs will PANIC with corresponding message.
You can press 'always continue' and ignore the PANIC, the simulation will continue as if alignment checking is not enabled.
I am merging the code in order to start making shortcuts between VMX emulation and SVM emulation.
Of course SVM emulation is incomplete, completely untested and not expected to work.
But someone could already take a look one the code and give some suggestions.
Also looking for anybody with existing SVM kernels - as simple as possible - for testing.
Status:
- exceptions intercept is not implemented yet
- IO intercept is not implemented yet
- MSR intercept is not implemented yet
- virtual interrupts are not implemented yet
- CPUID is not implemented yet
No advanced SVM featurez planned - I am implementing the very basic 'Pacifica' document from 2005 using QEMU code as reference.
SMP emulation. New implementation uses dynamic CPU quantum value and takes
full advantage of the trace cache. Each emulated processor will execute
the whole trace before switching to the next processor.
* It is also safe to use large (up to 16 instructions) quantum values for
the SMP emulation now and improve performance even further.
The same merge also completely fixes SF bug :
[3312237] stepN command might be not working properly
Handlers chaining speedups are also supported with SMP emulation now.
feature is enabled by default when configure with --enable-all-optimizations
option, to disable handlers chaining speedups configure with
--disable-handlers-chaining
The patch was posted in mailing list at Thu 6/16/2011.
Desription for CHANGES:
- Memory
- Added new configure option which enables RAM file backing for large guest
memory with a smaller amount host memory, without causing a panic when
host memory is exhausted (patch by Gary Cameron). To enable configure with
--enable-large-ramfile option.
environment. As a first step use it to skip some networking module tests.
- link BOCHS.EXE with MSVCRT if MSVC plugin support is enabled (building DLL
plugins with nmake still not possible - VS2008Ex workspace package coming soon)
- updated some messages for NE2000, PCI and USB
support compiles and links fine and the main object files for the plugin DLLs
are created. Since the gui and iodev makefiles are not ready yet, the link
stage must be done manually. Support for the search path defined in
LTDL_LIBRARY_PATH should be added when the DLL plugins compile and work.