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Hi,

This is a data point for IBM rs6000--591. aix 4.1.4.0, xlf 3,

xlf -O3 -qarch=pwr2 -qtune=pwr2.

I only got 16 clock ticks with memory usage 228 MB. Although

the machine has 512 MB memory, whenever the memory exceed 256 MB,

the program will not run, and I got the message saying that not

enough memory. I cheched limit, it was set properly. Until I

figure out how to use the 512 MB in full, 16 clock ticks is the

best I could get. ( or maybe 17 ).

Why do you use the best time ( shortest time ) ? Why not use

average time with more iterations ? using larger array means

average over space, using more iteration means average over time,

are they equivalent ? Average time is closer to the way machine

is used than best time, I think.

The system load is neally 0 excluding stream itself.

Best reguards.

h.huang

----------------------------------------------

Double precision appears to have 16 digits of accuracy

Assuming 8 bytes per DOUBLE PRECISION word

----------------------------------------------

Array size = 10000000

Offset = 0

The total memory requirement is 228 MB

You are running each test 10 times

The *best* time for each test is used

----------------------------------------------------

Your clock granularity/precision appears to be 10000 microseconds

The tests below will each take a time on the order

of 160000 microseconds

(= 16 clock ticks)

Increase the size of the arrays if this shows that

you are not getting at least 20 clock ticks per test.

----------------------------------------------------

WARNING: The above is only a rough guideline.

For best results, please be sure you know the

precision of your system timer.

----------------------------------------------------

Function Rate (MB/s) RMS time Min time Max time

Assignment: 695.6522 .2434 .2300 .2500

Scaling : 695.6522 .2434 .2300 .2500

Summing : 750.0000 .3345 .3200 .3400

SAXPYing : 750.0000 .3334 .3200 .3400

Sum of a is : 0.115330078110398751E+20

Sum of b is : 0.230660156211832781E+19

Sum of c is : 0.307546874927796787E+19

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