Hi,
Brian Whitney with FPS Computing.
I tried running your memory xfer program on our Model 500
SPARC series computer and came up with results that
are a little concerning to me.
First of all, the type in your program is
>>> parameter (N= 1 000 000)
>>> real a(N),b(N),c(N)
>>> real second
While in your test loop, you have a double precision constant.
This will cause extra operations in FORTRAN, consisting of type
conversions.
>>> do 30 j=1,N
>>> c(j) = 3.0d0*a(j)
>>> 30 continue
I believe you meant to have code run in 64-bit precision, because
results I achieved would say that is the case.
When I changed the Real declartion to real*8, the results look
correct to me for our machine.
Here are results for the FPS S511, SPARC based cpu with added vector
processor.
Code as presented...
systst2% x.x.
Timing calibration ; t = 6.45360 clicks
Assignment: Rate = 247.924 MB/s MFLOPS = 0.
Scaling: Rate = 102.594 MB/s MFLOPS = 6.41215
Summing: Rate = 186.564 MB/s MFLOPS = 7.77351
SAXPYing: Rate = 127.367 MB/s MFLOPS = 10.6139
Code modified to make 3.0d0 -> 3.0 (pure 32 bit run, I believe the
Mbyte calculation is 2x what it should be...)
systst2% x.x
Timing calibration ; t = 6.53050 clicks
Assignment: Rate = 245.004 MB/s MFLOPS = 0.
Scaling: Rate = 169.176 MB/s MFLOPS = 10.5735
Summing: Rate = 186.296 MB/s MFLOPS = 7.76235
SAXPYing: Rate = 185.753 MB/s MFLOPS = 15.4794
Code modified to have real -> real*8 (mbytes should be correct)
systst2% x8.x
Timing calibration ; t = 6.42171 clicks
Assignment: Rate = 249.155 MB/s MFLOPS = 0.
Scaling: Rate = 168.101 MB/s MFLOPS = 10.5063
Summing: Rate = 188.048 MB/s MFLOPS = 7.83534
SAXPYing: Rate = 189.218 MB/s MFLOPS = 15.7681
The last data are math library routines replacing your loops.
This just shows closer to what the limits of the machine are...
systst2% x2.x
Timing calibration ; t = 6.45340 clicks
Assignment: Rate = 247.931 MB/s MFLOPS = 0.
Scaling: Rate = 245.912 MB/s MFLOPS = 15.3695
Summing: Rate = 241.687 MB/s MFLOPS = 10.0703
SAXPYing: Rate = 244.302 MB/s MFLOPS = 20.3585
Brian Whitney
FPS Computing
3601 SW Murray Blvd
Beaverton, OR 97005
(503) 641-3151 x2682
keeper@fps.com
This archive was generated by hypermail 2b29 : Tue Apr 18 2000 - 05:23:01 CDT