[I tried to apply the low-latency patch as well, but it panicked all over the place and I gave up.] Same setup, notice the throughput and seek improvement over the last one with numthreads > 1. The difference the block size makes over throughput and seek grows a bit. Chunk doesn't do much. I liked to see the CPU level kept quite low for all the tests - pity I don't have the data for CPU for the other runs. Chunk is 4k, Stride is 4 and Block is 1024k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 15.6010 12.5% 10.2864 13.9% 115.323 0.86% /benc 512 4096 2 20.4883 17.2% 10.2005 13.6% 136.589 1.16% /benc 512 4096 4 20.9366 17.7% 10.3003 14.0% 149.157 1.36% /benc 512 4096 8 19.6439 16.6% 10.5238 14.5% 151.621 1.32% /benc 512 4096 16 18.1476 15.6% 10.9204 15.6% 152.436 1.31% /benc 512 4096 32 16.9452 15.0% 11.1384 16.6% 156.243 1.34% /benc 512 4096 64 15.8305 14.6% 11.2538 17.3% 160.884 1.39% Chunk is 4k, Stride is 2 and Block is 2048k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 16.1209 9.98% 13.7153 14.0% 131.054 0.72% /benc 512 4096 2 20.9963 13.2% 13.7167 14.3% 164.035 0.82% /benc 512 4096 4 21.8818 14.3% 13.6282 13.9% 180.413 0.99% /benc 512 4096 8 20.6298 13.7% 13.5595 14.1% 184.305 1.00% /benc 512 4096 16 18.9483 12.7% 13.5885 14.6% 187.326 1.00% /benc 512 4096 32 18.0542 12.3% 13.5149 14.9% 192.170 1.16% /benc 512 4096 64 16.9584 11.9% 13.3698 14.8% 198.426 1.22% Chunk is 4k, Stride is 1 and Block is 4096k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 16.3776 8.76% 14.4344 12.6% 137.307 0.61% /benc 512 4096 2 21.1011 11.8% 14.3730 12.6% 172.618 1.03% /benc 512 4096 4 22.1518 11.8% 14.3301 12.7% 192.878 1.06% /benc 512 4096 8 20.5643 11.0% 14.2763 12.7% 205.510 1.00% /benc 512 4096 16 19.4010 10.5% 14.2054 12.9% 214.981 1.05% /benc 512 4096 32 18.6990 10.2% 14.0910 12.9% 223.368 1.05% /benc 512 4096 64 17.5126 10.1% 13.9094 12.8% 229.203 1.08% Chunk is 8k, Stride is 8 and Block is 1024k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 15.3003 12.3% 10.2585 13.5% 115.921 0.95% /benc 512 4096 2 19.9035 17.1% 10.2193 13.4% 135.801 1.12% /benc 512 4096 4 20.8035 18.3% 10.2971 13.8% 147.715 1.25% /benc 512 4096 8 19.3439 16.9% 10.4701 14.2% 149.781 1.22% /benc 512 4096 16 17.5284 15.3% 10.8465 15.3% 151.820 1.19% /benc 512 4096 32 16.5331 14.8% 11.0786 16.3% 155.201 1.26% /benc 512 4096 64 15.5191 14.5% 11.2132 16.9% 160.103 1.33% Chunk is 8k, Stride is 4 and Block is 2048k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 16.3932 10.2% 13.8853 14.0% 127.661 0.54% /benc 512 4096 2 21.2495 13.5% 13.7953 13.9% 161.340 1.16% /benc 512 4096 4 22.1637 14.3% 13.7668 13.9% 178.509 1.20% /benc 512 4096 8 20.9219 13.6% 13.6549 14.3% 182.435 1.15% /benc 512 4096 16 19.3307 12.8% 13.6601 14.8% 185.122 1.16% /benc 512 4096 32 18.3366 12.3% 13.5734 15.0% 188.539 1.17% /benc 512 4096 64 17.0937 12.1% 13.3963 14.9% 191.466 1.18% Chunk is 8k, Stride is 2 and Block is 4096k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 16.4207 7.69% 14.6141 13.2% 135.277 0.64% /benc 512 4096 2 20.9161 10.7% 14.3866 12.7% 170.192 0.85% /benc 512 4096 4 22.1052 12.1% 14.3446 12.9% 190.909 1.00% /benc 512 4096 8 20.6014 11.2% 14.3083 13.1% 204.792 1.10% /benc 512 4096 16 19.4375 10.6% 14.1980 13.1% 215.398 1.16% /benc 512 4096 32 18.4815 10.2% 14.0873 13.2% 223.535 1.22% /benc 512 4096 64 17.7573 10.1% 13.9099 13.0% 227.065 1.21% Chunk is 16k, Stride is 16 and Block is 1024k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 15.4163 12.1% 10.3258 13.6% 115.377 0.98% /benc 512 4096 2 20.0857 16.7% 10.2159 13.7% 135.971 1.10% /benc 512 4096 4 20.9112 17.8% 10.2866 13.6% 147.933 1.15% /benc 512 4096 8 19.6638 16.7% 10.4764 14.1% 150.793 1.08% /benc 512 4096 16 18.0633 15.5% 10.8520 15.2% 152.745 1.08% /benc 512 4096 32 16.9140 14.9% 11.0847 16.2% 156.321 1.21% /benc 512 4096 64 15.8136 14.5% 11.1641 16.8% 160.206 1.28% Chunk is 16k, Stride is 8 and Block is 2048k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 16.2950 9.38% 13.7594 13.5% 127.262 0.89% /benc 512 4096 2 20.9210 13.1% 13.7470 13.7% 158.922 1.09% /benc 512 4096 4 21.2644 13.4% 13.6635 13.9% 176.597 1.11% /benc 512 4096 8 20.3493 13.6% 13.5733 14.0% 180.716 1.11% /benc 512 4096 16 19.9698 13.5% 13.5598 14.4% 183.124 1.10% /benc 512 4096 32 18.7750 12.7% 13.4844 14.6% 187.895 1.16% /benc 512 4096 64 17.8050 12.3% 13.3357 14.8% 192.223 1.28% Chunk is 16k, Stride is 4 and Block is 4096k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 16.4439 8.09% 14.6853 12.8% 138.135 0.82% /benc 512 4096 2 21.0736 11.6% 14.5660 12.7% 173.144 0.97% /benc 512 4096 4 22.1643 12.1% 14.4611 12.7% 193.189 1.15% /benc 512 4096 8 20.9292 11.8% 14.3801 12.9% 206.803 1.11% /benc 512 4096 16 19.8257 11.1% 14.2720 13.0% 217.608 1.09% /benc 512 4096 32 18.8483 10.8% 14.1691 13.1% 225.369 1.12% /benc 512 4096 64 18.1167 10.7% 13.9423 13.0% 231.754 1.13% Chunk is 32k, Stride is 32 and Block is 1024k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 15.3845 12.6% 10.3361 13.9% 115.953 0.86% /benc 512 4096 2 20.4718 16.4% 10.2939 13.9% 137.124 1.33% /benc 512 4096 4 21.0847 17.4% 10.3784 14.0% 149.654 1.27% /benc 512 4096 8 20.3708 17.3% 10.5419 14.5% 151.078 1.23% /benc 512 4096 16 18.5314 16.0% 10.9237 15.4% 153.269 1.24% /benc 512 4096 32 17.3907 15.3% 11.1377 16.4% 156.872 1.24% /benc 512 4096 64 16.2529 15.0% 11.2147 17.0% 162.340 1.35% Chunk is 32k, Stride is 16 and Block is 2048k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 16.2423 9.86% 13.8463 13.7% 130.200 0.87% /benc 512 4096 2 20.8685 13.2% 13.6589 13.7% 161.369 1.08% /benc 512 4096 4 20.9599 13.7% 13.5876 13.8% 178.935 1.26% /benc 512 4096 8 20.0932 13.1% 13.5489 14.0% 181.649 1.22% /benc 512 4096 16 19.2203 12.8% 13.5971 14.4% 186.918 1.16% /benc 512 4096 32 18.4283 12.3% 13.5238 14.7% 192.295 1.20% /benc 512 4096 64 17.3383 12.2% 13.3873 14.8% 197.203 1.24% Chunk is 32k, Stride is 8 and Block is 4096k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 16.2917 8.24% 14.3896 12.7% 139.385 0.52% /benc 512 4096 2 21.0171 11.3% 14.3873 12.7% 174.463 0.95% /benc 512 4096 4 22.0889 11.8% 14.3301 12.7% 194.742 1.02% /benc 512 4096 8 20.8408 11.1% 14.3166 12.9% 207.188 1.13% /benc 512 4096 16 19.4878 10.4% 14.2575 12.9% 217.132 1.21% /benc 512 4096 32 18.6783 10.4% 14.1580 13.1% 224.634 1.27% /benc 512 4096 64 17.4066 10.1% 13.9654 12.9% 230.786 1.36% Chunk is 64k, Stride is 64 and Block is 1024k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 15.1561 12.8% 10.0670 13.3% 114.862 0.51% /benc 512 4096 2 20.0472 16.9% 10.0650 13.3% 135.798 1.03% /benc 512 4096 4 20.7604 17.8% 10.1915 13.6% 148.900 1.11% /benc 512 4096 8 19.4354 17.0% 10.3932 14.1% 149.675 1.14% /benc 512 4096 16 18.2348 16.1% 10.7893 15.3% 152.419 1.15% /benc 512 4096 32 17.1624 15.5% 11.0227 16.2% 155.514 1.27% /benc 512 4096 64 16.0166 15.0% 11.1566 16.9% 159.187 1.30% Chunk is 64k, Stride is 32 and Block is 2048k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 16.0005 9.59% 13.8400 13.6% 131.088 0.91% /benc 512 4096 2 20.8495 12.9% 13.7202 13.5% 164.177 1.14% /benc 512 4096 4 21.9505 13.9% 13.6742 13.7% 181.987 1.34% /benc 512 4096 8 20.5812 13.4% 13.5827 13.7% 184.571 1.40% /benc 512 4096 16 19.6149 13.1% 13.5858 14.3% 189.240 1.41% /benc 512 4096 32 18.7084 12.7% 13.4983 14.6% 192.459 1.33% /benc 512 4096 64 17.6659 12.6% 13.3551 14.6% 200.304 1.35% Chunk is 64k, Stride is 16 and Block is 4096k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 16.3363 8.35% 14.5453 13.4% 140.008 0.80% /benc 512 4096 2 20.8031 10.4% 14.4298 12.9% 173.570 0.95% /benc 512 4096 4 21.8080 11.5% 14.4230 12.8% 193.989 1.06% /benc 512 4096 8 20.9706 11.3% 14.3233 12.8% 207.593 1.16% /benc 512 4096 16 19.6667 10.6% 14.2004 13.0% 217.407 1.17% /benc 512 4096 32 19.0165 10.4% 14.0784 13.1% 224.087 1.21% /benc 512 4096 64 17.5991 10.2% 13.8814 13.0% 228.730 1.30% Chunk is 128k, Stride is 128 and Block is 1024k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 15.5102 12.0% 10.1153 13.8% 115.105 0.86% /benc 512 4096 2 20.3635 17.6% 10.0623 13.7% 135.936 1.07% /benc 512 4096 4 20.5054 18.1% 10.1767 13.8% 148.098 1.22% /benc 512 4096 8 19.7445 17.7% 10.3914 14.1% 150.733 1.13% /benc 512 4096 16 18.3066 16.4% 10.7821 15.2% 153.055 1.12% /benc 512 4096 32 17.0332 15.6% 11.0433 16.3% 157.292 1.21% /benc 512 4096 64 15.8949 15.2% 11.1489 16.8% 160.679 1.33% Chunk is 128k, Stride is 64 and Block is 2048k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 16.1990 10.8% 13.8461 14.0% 130.213 0.48% /benc 512 4096 2 20.9119 14.1% 13.7865 13.8% 160.984 0.82% /benc 512 4096 4 21.9430 14.9% 13.6509 13.8% 178.521 0.81% /benc 512 4096 8 20.3268 13.8% 13.5647 14.0% 182.807 0.85% /benc 512 4096 16 18.9984 12.8% 13.5475 14.4% 186.478 1.01% /benc 512 4096 32 18.3722 12.6% 13.4917 14.7% 190.384 1.03% /benc 512 4096 64 17.5364 12.6% 13.3612 14.7% 198.293 1.07% Chunk is 128k, Stride is 32 and Block is 4096k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 16.1656 8.39% 14.5966 13.1% 137.808 0.51% /benc 512 4096 2 20.9455 10.9% 14.4800 12.5% 173.108 0.71% /benc 512 4096 4 21.9999 12.2% 14.4194 12.7% 194.136 0.92% /benc 512 4096 8 20.1739 11.2% 14.3315 12.6% 208.072 1.05% /benc 512 4096 16 19.2780 10.7% 14.2129 12.9% 216.680 1.24% /benc 512 4096 32 18.3973 10.4% 14.0814 12.9% 224.035 1.24% /benc 512 4096 64 17.7127 10.3% 13.8522 12.8% 228.329 1.33% Chunk is 256k, Stride is 256 and Block is 1024k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 15.1877 12.3% 10.2163 13.3% 115.450 0.77% /benc 512 4096 2 20.2308 16.7% 10.1913 13.6% 136.842 0.92% /benc 512 4096 4 20.4640 16.8% 10.2889 14.0% 149.899 0.98% /benc 512 4096 8 19.6731 16.5% 10.4774 14.4% 151.799 1.00% /benc 512 4096 16 18.6402 16.0% 10.8756 15.6% 154.617 1.03% /benc 512 4096 32 17.2176 15.2% 11.1147 16.5% 158.221 1.08% /benc 512 4096 64 15.8047 14.6% 11.1998 17.0% 163.593 1.18% Chunk is 256k, Stride is 128 and Block is 2048k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 16.3325 10.9% 13.6510 13.4% 129.537 0.80% /benc 512 4096 2 20.9725 14.4% 13.6387 13.5% 161.077 1.06% /benc 512 4096 4 21.8188 14.6% 13.6153 13.8% 178.513 1.21% /benc 512 4096 8 20.4267 13.7% 13.5551 13.9% 183.241 1.20% /benc 512 4096 16 19.2711 13.0% 13.5718 14.5% 187.991 1.17% /benc 512 4096 32 18.2718 12.5% 13.5096 14.8% 193.254 1.24% /benc 512 4096 64 17.1941 12.1% 13.3542 14.7% 197.923 1.25% Chunk is 256k, Stride is 64 and Block is 4096k Dir Size BlkSz Thr# Read (CPU%) Write (CPU%) Seeks (CPU%) ----- ------ ------- ---- ------------- -------------- -------------- /benc 512 4096 1 16.3424 7.82% 14.4882 12.8% 137.593 0.48% /benc 512 4096 2 21.2511 11.1% 14.5220 12.5% 175.904 0.59% /benc 512 4096 4 21.9078 11.4% 14.4173 12.5% 195.405 0.81% /benc 512 4096 8 20.3640 10.7% 14.3358 12.7% 207.347 0.98% /benc 512 4096 16 19.2420 10.3% 14.2157 12.8% 217.278 1.02% /benc 512 4096 32 18.1576 10.1% 14.0840 13.0% 226.612 1.06% /benc 512 4096 64 17.1923 10.1% 13.8945 13.0% 230.336 1.15% Cheers, -- _/\ Christian Reis is sometimes [EMAIL PROTECTED] \/~ suicide architect | free software advocate | mountain biker
