Beowulf Home > Benchmark Results

Benchmark Results:

  1. MHz vs. cost curves for Intel PIII and AMD Athlon CPU have been plotted. "Knee" occurs at 800 MHz for PIII, 900 MHz for Athlon; both of these CPUs cost approximately $280.
  2. Intel PIII CPUs only have 16K+16K L1 cache (compared to 64K+64K L1 cache for AMD Athlons). However, both PIII and Athlon CPUs with 800Mhz or higher clock speeds now have 256K L2 full-speed caches. This make the small size of the L1 cache for PIII CPUs less of an issue.
  3. The UWM group said the typical array size for binary inspiral search FFTs would be about 8 Mbytes, corresponding to approximately 15 minutes worth of interferometer data, downsampled to 1024 Hz. (1024*15*60*8bytes = 7372800 bytes ~ 8388608 Mbytes)
  4. Fitra has contacted a vendor who will supply loaners for a 800 MHz PIII and 900 MHz Athlon (CPU + motherboard).
  5. UWM FFTW benchmarks for 600 MHz PIII and Athlons (100 MHz bus) were rerun verifying last years results. PIII performs about 30% more MFlops for large array size (>64K elements), while Athlon performs better for smaller array sizes (40% better for 16K element arrays).
  6. UWM FFTW benchmarks show that 800 MHz PIII performs better than 900 MHz Athlon for large array sizes (190 MFlops vs. 150 MHz).
  7. UWM FFTW benchmarks for 733 and 800 MHz PIIIs show an increase in performance of about 33 MFlops for the 66 MHz increase in clock speed (at large array size). We assume that this relationship is linear (slope = .5 MFlops/MHz) and is the same for Athlons as well.
  8. A plot of MFlops/$ vs. MHz shows that the 800 MHz PIII gives us the best performance per dollar as we had guessed would be the case.
  9. 800 MHz PIII CPU was already bought.
  10. Purchased one motherboard and got 3 other loaners to do benchmarking for the 800 MHz PIII CPU. (Motherboards: Gigabyte, ASUS-CUV4X, ASUS-CUSL2 815E, and Intel 815E).
  11. Benchmarking of motherboards show that the two ASUS and Intel motherboards are almost equivalent. The Gigabyte motherboard performs about 33% worse (150 MFlops vs. 190 MFlops for large array sizes.)
  12. We will choose the cheaper of the Intel 815E or ASUS CUSL2-815E motherboard since their performance is about the same. (Of the two ASUS motherboards, ASUS-CUSL2 815E is preferred because it has ATA-100 disk controller protocol.
  13. Based on the above benchmarks, we started the bidding process to purchase 48 Intel PIII 800 MHz CPUs and the cheaper of the Intel 815E or ASUS CUSL2-815E motherboards (without an on-board ethernet card for ease of maintenance and troubleshooting).