Timing Data for a Pentium II Running Linux D. A.Atkinson The execution times of a set of computational programs run on a modern Pentium II system under the Linux operating system are tabulated below. The computer employed a 233 MHz Pentium II CPU with 512 Kbytes of integrated L2 cache memory. The main RAM memory is 128 Mbytes connected to the CPU by a PCI bus. The Linux (2.0.38) operating system was used, and the test code was compiled using the GNU C-compiler (version 2.7.2). The optimization switch -O3 was used in all compilations. All the computations timed use double precision arithmetic. ----------------------------------------------------------------------------- ----------------------------------------------------------------------------- 1. The Linpac benchmark: A large linear system is solved. dimension time (sec.) rate (Mflops) 300 0.277 65.6 (*) 600 3.83 36.8 900 13.08 37.3 1200 30.92 37.4 1500 59.33 37.9 1800 103.13 37.8 (*) This benchmark used 'timslpac' with 10 iterations. ----------------------------------------------------------------------------- ----------------------------------------------------------------------------- 2. Matrix multiplication: The product of two real square matrices is computed. ----------------------------------------------------------------------------- dimension time (sec.) rate (Mflops) 250 0.41 76.2 500 6.35 39.4 750 21.27 39.7 1000 50.47 39.6 1250 104.10 37.5 1500 182.64 37.0 ----------------------------------------------------------------------------- ----------------------------------------------------------------------------- 3. Matrix inverse: The inverse of a real square matrix is computed. ----------------------------------------------------------------------------- dimension time (sec.) 300 1.03 600 17.68 900 62.61 1200 149.23 ----------------------------------------------------------------------------- ----------------------------------------------------------------------------- 4. Eigen system problems: ----------------------------------------------------------------------------- a. real symmetric matrix eigenvalues egenvalues & vectors dimension time (sec.) time (sec.) 200 0.23 1.21 400 2.06 13.00 600 8.05 46.17 800 21.17 111.31 b. hermitian matrix eigenvalues egenvalues & vectors dimension time(sec.) time (sec.) 200 0.76 3.56 400 6.86 30.85 600 25.24 109.97 800 61.48 266.03 ----------------------------------------------------------------------------- ----------------------------------------------------------------------------- 5. Fourier transforms: a. Compute the transform of a complex series using a radix-2 based FFT. ----------------------------------------------------------------------------- N (length=2^N) time (sec.) rate (Mflops) (*) 16 65536 0.22 66.7 18 262144 1.05 62.9 20 1048576 4.68 62.7 22 4194304 20.45 63.1 (*) Rate computation based on operation count = 14*N*(2^N) ----------------------------------------------------------------------------- b. Compute a general radix Fast Fourier Transform. ----------------------------------------------------------------------------- N time (sec.) 50000 0.48 200000 2.56 1000000 14.33 ----------------------------------------------------------------------------- ----------------------------------------------------------------------------- 6. Sorting: Sort a series of double precision floating point numbers. ----------------------------------------------------------------------------- series length merge sort quick sort heap sort shell sort (sec.) (sec.) (sec.) (sec.) 100,000 0.47 0.52 0.73 1.01 500,000 3.22 3.51 5.27 7.70 1,00,0000 7.30 7.49 12.14 19.09 ----------------------------------------------------------------------------- ----------------------------------------------------------------------------- 7. Function evaluation: Compute Bessel functions of the first kind, Jn(x), on a grid in order n and argument x. ----------------------------------------------------------------------------- evaluations time (sec.) dt per evaluation 250,000 2.06 8.24 usec ----------------------------------------------------------------------------- ----------------------------------------------------------------------------- 8. Numerical integration: Compute complete elliptic integrals of the first kind at evenly spaced values of the parameter k*k. ----------------------------------------------------------------------------- evaluations time (sec.) dt per evaluation 50,000 2.24 44.8 usec ----------------------------------------------------------------------------- ----------------------------------------------------------------------------- 9. Random Normal Generation: Generate pseudorandom normal deviates. ----------------------------------------------------------------------------- number generated time (sec.) dt per evaluation 1,000,000 0.85 0.85 usec -----------------------------------------------------------------------------