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I am thinking of going for a Mac Pro to replace my 3 year old MaC Mini. Virtual Acorn is a bit too slow on this G4 1.4 MHz Mini so I would like to know if a Mac Pro is seen to be fast. Does anyone have any performance tests yet to compare with RISC OS native machines? Similar to the ones that were done in Archive (IIRC) for VA on PCs vs native RISC PC and Iyonix?

If no tests have been done, does anyone have any view of the performance of VA with a high spec Core 2 duo Mac Pro?

A Core 2 Mac will give similar (perhaps slightly higher) figures than a Windows machines with the same spec. The "speed" you get depends on what the application concerned is doing. Anything that does a lot of disc activity will be much faster than any "real" machine.

The "emulated" CPU will be several times the speed of a Risc PC (my 2.2Ghxz Core 2 desktop Windows machine gives a BogoMips of 400 - which is just over 4 x the speed of an SA RiscPC).

A modern Core 2 Mac should be as fast, if not quite a bit faster, than an Iyonix.

I use RISC OS only on my iMac (2.4Ghz core 2 duo )
I can tell you it is faster with everything (a lot faster as my A9home /Omega or StrongArm RPC.)

As long as you don't need special podule's for your daily work there is no need to keep native RO hardware

(oeps not really the truth..... the only thing I mis on VA for Mac is scrolling with the mouse - but I can live with it)

The Mac is now here and loaded up with VARPC (plus Windows and Ubuntu in VMWare Fusion partitions), so I've done some tests on file reading and writing speeds. I chose two file sizes, 128 Bytes and 393KBytes and timed loading and saving these from 10 times in a row to 1000, controlled by a BASIC program. Broad brush the number of repeats did not make a large difference to the saving and reading rates.

I have put a summary of the results on this site (as I can't get non-proportional formatting here):

http://www.tim.ukpub.net/riscos/VAvsIYOandRPCSA.html

The significant thing is that the Iyonix is clearly faster than RISC OS on the Mac, even in write speeds; this surprised me as I remember tests of VARPC on Windows machines showed that they were very fast at disc operations.

The Mac has 256 MBytes of RAM allocated to VARPC and runs at 2.8MHz with two quad-core processors.

Now to find some means of comparing processing speeds.

It's quite possible that you are accidentally ending up checking the speed of BASIC itself. Included with VRPC is the APDL Disc Speed checking program - run this on both machines. Remember to test from HostFS on the VRPC - ADFS will be much slower and is there for compatability purposes with some
applications (Sibelius, FontDirPro)

In general terms, your data tie in with our own test results published in Archive mag Vol 20 Issue 8 (May 2007), comparing Iyonix etc against VirtualRPC running on an E6600 PC (dual core, 2.40GHz). I can send you a PDF copy of the report if it will help.

All our test results involving Basic were indeed barely on a par (or rather less) compared with Iyonix. However, non-Basic tests returned typically 200-500% improvements, very likely enhanced by the ultra-fast disc access speeds (HostFS).

If you wish to compare processor performance, we recommend looking at pure 'number-crunching' events such as OCR, converting bitmaps to vector graphics (using e.g. Trace) and document page-rendering, particularly colour work. In other words, 'real-life' activities rather than the somewhat synthetic tests of Dhrystones, Bogo-MIPS and so on.

HTH, Geoff Peck
pp T.O.M.S.