I can't tell you what to expect from an AMD64 with today's software, but
Quartus II 3.0 does not run on X86-64. See
The server versions of Win2000 can handle up to 32GB of RAM, if that's
((Unless there's a version of the compiler specifically for a 64-bit
On Fri, 27 Feb 2004 15:04:46 -0800, Pete Fraser wrote:
We're currently running a 3 GHz Pentium with 2 GB
memory under Windows 2000.
The server versions of Win2000 can handle up to 32GB of RAM, if that's
the main limiting factor. Can get pricey, though
We hope to speed things up by 15-20%, by going
to AMD X86-64 and / or Linux.
Has anybody tried this?
Any feedback?
Unless there's a version of the compiler specifically for a 64-bit
architecture, then you're unlikely to see any real speed gain to
justify the cost, and even if there is, I doubt the gains would be all
that impressive.
64-bit CPUs really only come into their own in applications that need
to access very large virtual address spaces (>4GB). Mostly, that's
server-type apps. The need for 64-bit arithmetic is likely very small
in this case.
Can the compiler multi-thread? If so, a mobo with a couple of HT Xeons
(4 CPUs), will give you all the extra horsepower you'll need.
If not, a dual-processor system would still perform a lot better,
since one CPU can work flat-out on the compile, while the other is
handling the OS and other background tasks.
All this assumes that the compiler's performance is, in fact, CPU or
memory bound as you imply. Are you actually certain that this is
indeed the case? Might a faster disk system help?
--
Max
On Fri, 27 Feb 2004 15:04:46 -0800, Pete Fraser wrote:
We're currently running a 3 GHz Pentium with 2 GB
memory under Windows 2000.
The server versions of Win2000 can handle up to 32GB of RAM, if that's
the main limiting factor. Can get pricey, though
We hope to speed things up by 15-20%, by going
to AMD X86-64 and / or Linux.
Has anybody tried this?
Any feedback?
Unless there's a version of the compiler specifically for a 64-bit
architecture, then you're unlikely to see any real speed gain to
justify the cost, and even if there is, I doubt the gains would be all
that impressive.
64-bit CPUs really only come into their own in applications that need
to access very large virtual address spaces (>4GB). Mostly, that's
server-type apps. The need for 64-bit arithmetic is likely very small
in this case.
Can the compiler multi-thread? If so, a mobo with a couple of HT Xeons
(4 CPUs), will give you all the extra horsepower you'll need.
If not, a dual-processor system would still perform a lot better,
since one CPU can work flat-out on the compile, while the other is
handling the OS and other background tasks.
All this assumes that the compiler's performance is, in fact, CPU or
memory bound as you imply. Are you actually certain that this is
indeed the case? Might a faster disk system help?
--
Max
Provided the peak memory consumption of Quartus for the compilation in
64-bitness _is_ mostly about addressable memory -- it is rare that 64-bit
I think the OP was refering to the wider datapaths.
Yes, wider memory interfaces/cache data lines can help, but as you say, this
Or running synthesis, place & route, static timing analysis etc. on an
We can all speculate about the relative merits of processorHi Jim,
I think the OP was refering to the wider datapaths.
I don't know the cycle level details of the AMD or Intel 64 bit
but an obvious and simple speed gain can come from a wider HW fetch.
(even running < 64 bit opcodes ) and then a simple check if the next
opcode / next data value is in that block.
Yes, wider memory interfaces/cache data lines can help, but as you say, this
is independent of op-code size. If I recall correctly, AMD and Intel
processors already fetch 64-bit blocks, but this may have been increased.
The latest m/b chipsets for both families of processors use dual-channel DDR
(128-bits wide) and so I would not be surprised if they've increased the
size of fetches.
As vendors introduce 64-bit capable processors (such as Opteron), they often
also enhance various aspects of the CPU architecture in ways that help both
32- and 64-bit code. And while the 64-bitness of x86-64 may not matter much
for speed, the doubling of the register files etc. could result in faster
performance.
It's every computer engineers dream to be a processor architect, isn't it?
The only common misconception is that swapping for a 64-bit processor
Data is only data if it's meaningful. The use of 64-bit arithmetic
I had assumed that had happened already. Silly me.
Not in a low-spec machine like that, no. The options in a laptop are
That doesn't mean a lot. You only need to add more memory if you're
I would like to get see synthesis and place and route tools I could
I suspected that might be the case, but I wasn't quite sure.
While the extra cache is important in itself, much of the performance
I doubt you'd get anywhere near. Trying to implement those algorithms