answer // further // Benchmark - 64 bit much slower than 32 bit
- To: mathgroup at smc.vnet.net
- Subject: [mg111799] answer // further // Benchmark - 64 bit much slower than 32 bit
- From: "Scot T. Martin" <smartin at seas.harvard.edu>
- Date: Fri, 13 Aug 2010 06:58:26 -0400 (EDT)
In case any one else runs into a similar problem, I sorted out the answer to the slowness below. I pulled out one memory strip to drop from 8 MB to 6 MB and, presto, performance went from slow (rating of 1.13) to ultrafast (rating of 5.50). How to explain this? I believe it goes back to "following the manufacturer's recommendation". That is, this computer is provided in configurations of 6 MB or 12 MB. My IT department bought a 2 MB memory strip and pumped it up from 6 to 8 MB. It seems there must be some kind of hardware inbalancing in the memory that influences the speed of some calculations; details are beyond my technical level. But the problem has been fixed by "following the manufacturer's suggestion on memory configurations". ---------- Forwarded message ---------- Date: Wed, 11 Aug 2010 19:38:13 -0400 (EDT) From: Scot T. Martin <smartin at seas.harvard.edu> To: mathgroup at smc.vnet.net Subject: [mg111799] further // Benchmark - 64 bit much slower than 32 bit (fwd) This issue is more subtle than outlined in the last email because I ran Benchmark[] on yet another computer that also has Windows 7 64-bit and got very good results. Here is a full comparison --- any insights on the slow one? **** FASTEST **** Intel(R) Core(TM) i5 CPU 650 @3.20GHz, 8.00 GB === System Information === Machine Name: smartin-t1500pc System: Microsoft Windows (64-bit) Date: August 11, 2010 Mathematica Version: 7.0.0 Benchmark Result: 4.71 smartin-t1500pc Microsoft Windows (64-bit) 18.3 1.05 0.36 0.52 1.22 1.67 0.22 0.50 1.81 2.11 1.08 1.84 1.34 1.11 1.59 1.89 **** NEXT FASTEST **** Intel(R) Core(TM)2 Duo CPU E8500 at 3.16 Ghz, 2.75 GB RAM === System Information === Machine Name: martin2 System: Microsoft Windows (32-bit) Date: August 11, 2010 Mathematica Version: 7.0.0 Benchmark Result: 4.12 martin2 Microsoft Windows (32-bit) 20.9 1.20 0.59 0.83 1.25 1.89 0.44 0.77 2.61 1.83 1.42 2.05 1.45 1.25 1.42 1.91 *** WAY TOO SLOW (new system) *** Intel(R) Xeon(R) CPU, W3680 at 3.33 GHz, 8.00 GB install, Windows 7 professional 64 bit === System Information === Machine Name: profmartinoffic System: Microsoft Windows (64-bit) Date: August 11, 2010 Mathematica Version: 7.0.0 Benchmark Result: 1.13 profmartinoffic Microsoft Windows (64-bit) 76.2 1.87 0.33 0.39 26.10 1.83 0.23 0.48 1.89 1.70 0.84 1.72 1.05 1.15 23.80 12.80 original email: Folks, just installed Mathematica on new Windows 7 64-bit machine and Benchmark[] is much slower than on 32-bit Windows XP. MathematicaMark7 Rating of new system is 1.13 compared to 4.12 of old system. Any explanations for this? Details are below. Are many of Mathematica's routines still in 32-bit and thus slower on 64-bit machine? Is this an issue related to Windows XP compared to Windows 7 vis-a-vis Mathematica? Needless to say, new system is much better in terms of CPU, memory, etc., so this result is very surprising to me. I'd like to know what I can adjust to get a blazing Benchmark!