Memory bandwidth

Using the program cachebench the results are:

# ./cachebench

                Memory Set Library Cache Test

C Size          Nanosec         MB/sec          % Chnge
-------         -------         -------         -------
256             0.05            20205.70        1.00           
256             0.05            20210.63        1.00           
384             0.05            20445.46        0.99           
384             0.05            20447.49        1.00           
512             0.04            22799.44        0.90           
512             0.04            22851.47        1.00           
768             0.04            26378.00        0.87           
768             0.04            26362.02        1.00           
1024            0.03            27987.20        0.94           
1024            0.03            27868.26        1.00           
1536            0.03            30555.05        0.91           
1536            0.03            30600.60        1.00           
2048            0.03            31588.43        0.97           
2048            0.03            31572.33        1.00           
3072            0.03            31405.71        1.01           
3072            0.03            31397.64        1.00           
4096            0.03            33861.48        0.93           
4096            0.03            33910.90        1.00           
6144            0.03            34731.45        0.98           
6144            0.03            34755.92        1.00           
8192            0.03            35086.88        0.99           
8192            0.03            35120.02        1.00           
12288           0.03            34854.81        1.01           
12288           0.03            34863.39        1.00           
16384           0.03            35282.06        0.99           
16384           0.03            35286.52        1.00           
24576           0.03            35720.84        0.99           
24576           0.03            35720.80        1.00           
32768           0.04            26525.08        1.35           
32768           0.04            26534.71        1.00           
49152           0.06            15003.31        1.77           
49152           0.06            15004.54        1.00           
65536           0.06            15026.68        1.00           
65536           0.06            15029.94        1.00           
98304           0.06            15048.04        1.00           
98304           0.06            15052.69        1.00           
131072          0.06            15060.22        1.00           
131072          0.06            15065.03        1.00           
196608          0.06            15073.04        1.00           
196608          0.06            15076.64        1.00           
262144          0.06            15079.84        1.00           
262144          0.06            15080.40        1.00           
393216          0.06            15086.09        1.00           
393216          0.06            15087.90        1.00           
524288          0.06            15088.01        1.00           
524288          0.06            15090.52        1.00           
786432          0.06            15089.41        1.00           
786432          0.06            15092.04        1.00           
1048576         0.06            15009.05        1.01           
1048576         0.06            15013.61        1.00           
1572864         0.06            14675.01        1.02           
1572864         0.06            14690.48        1.00           
2097152         0.07            14507.26        1.01           
2097152         0.07            14527.73        1.00           
3145728         0.21            4640.97         3.13           
3145728         0.21            4641.73         1.00           
4194304         0.21            4640.42         1.00           
4194304         0.21            4639.80         1.00           
6291456         0.21            4638.57         1.00           
6291456         0.21            4641.71         1.00           
8388608         0.21            4641.45         1.00           
8388608         0.21            4641.38         1.00           
12582912        0.21            4639.89         1.00           
12582912        0.21            4641.15         1.00           
16777216        0.21            4635.95         1.00           
16777216        0.21            4638.22         1.00           

                Memory Copy Library Cache Test

C Size          Nanosec         MB/sec          % Chnge
-------         -------         -------         -------
256             0.03            27257.58        1.00           
256             0.04            27240.95        1.00           
384             0.03            29720.92        0.92           
384             0.03            28648.10        1.04           
512             0.03            31178.50        0.92           
512             0.03            31187.37        1.00           
768             0.03            32859.87        0.95           
768             0.03            32851.33        1.00           
1024            0.03            32810.48        1.00           
1024            0.03            32722.88        1.00           
1536            0.04            25218.32        1.30           
1536            0.04            25301.41        1.00           
2048            0.04            26790.56        0.94           
2048            0.04            26784.68        1.00           
3072            0.03            28591.99        0.94           
3072            0.03            28568.35        1.00           
4096            0.03            29342.82        0.97           
4096            0.03            29395.67        1.00           
6144            0.03            30380.29        0.97           
6144            0.03            30379.74        1.00           
8192            0.03            30895.29        0.98           
8192            0.03            30896.40        1.00           
12288           0.03            31428.01        0.98           
12288           0.03            31431.92        1.00           
16384           0.03            28911.49        1.09           
16384           0.03            28901.91        1.00           
24576           0.06            15160.88        1.91           
24576           0.06            15163.85        1.00           
32768           0.06            15465.43        0.98           
32768           0.06            15462.28        1.00           
49152           0.06            15812.25        0.98           
49152           0.06            15816.79        1.00           
65536           0.06            16020.25        0.99           
65536           0.06            16025.29        1.00           
98304           0.06            16218.49        0.99           
98304           0.06            16224.20        1.00           
131072          0.06            16325.38        0.99           
131072          0.06            16319.58        1.00           
196608          0.06            16432.16        0.99           
196608          0.06            16421.04        1.00           
262144          0.06            16478.84        1.00           
262144          0.06            16473.13        1.00           
393216          0.06            16481.93        1.00           
393216          0.06            16479.39        1.00           
524288          0.06            16482.07        1.00           
524288          0.06            16482.70        1.00           
786432          0.06            16378.76        1.01           
786432          0.06            16370.23        1.00           
1048576         0.06            16384.89        1.00           
1048576         0.06            16390.15        1.00           
1572864         0.07            12763.70        1.28           
1572864         0.07            12786.26        1.00           
2097152         0.08            11335.55        1.13           
2097152         0.08            11340.17        1.00           
3145728         0.11            8450.05         1.34           
3145728         0.11            8446.56         1.00           
4194304         0.15            6548.52         1.29           
4194304         0.15            6551.65         1.00           
6291456         0.18            5372.22         1.22           
6291456         0.18            5369.39         1.00           
8388608         0.19            5088.09         1.06           
8388608         0.19            5083.32         1.00           
12582912        0.19            4985.97         1.02           
12582912        0.19            4984.00         1.00           
16777216        0.19            4982.10         1.00           
16777216        0.19            4976.06         1.00           

                double Read Cache Test

C Size          Nanosec         MB/sec          % Chnge
-------         -------         -------         -------
256             3.75            2035.09         1.00           
256             3.75            2034.92         1.00           
384             3.75            2034.97         1.00           
384             3.75            2035.07         1.00           
512             3.75            2035.35         1.00           
512             3.75            2035.06         1.00           
768             3.79            2011.75         1.01           
768             3.79            2011.86         1.00           
1024            3.78            2017.48         1.00           
1024            3.78            2017.71         1.00           
1536            3.77            2023.52         1.00           
1536            3.77            2023.31         1.00           
2048            3.76            2026.62         1.00           
2048            3.76            2026.46         1.00           
3072            3.76            2029.42         1.00           
3072            3.76            2029.07         1.00           
4096            3.76            2027.86         1.00           
4096            3.76            2027.50         1.00           
6144            3.76            2030.16         1.00           
6144            3.76            2030.24         1.00           
8192            3.76            2029.64         1.00           
8192            3.76            2029.94         1.00           
12288           3.76            2030.85         1.00           
12288           3.76            2030.39         1.00           
16384           3.76            2030.98         1.00           
16384           3.76            2030.92         1.00           
24576           3.76            2031.55         1.00           
24576           3.76            2031.32         1.00           
32768           3.76            2031.11         1.00           
32768           3.76            2030.82         1.00           
49152           3.76            2031.34         1.00           
49152           3.76            2031.40         1.00           
65536           3.76            2031.45         1.00           
65536           3.76            2031.40         1.00           
98304           3.76            2031.61         1.00           
98304           3.76            2031.50         1.00           
131072          3.76            2031.78         1.00           
131072          3.75            2031.83         1.00           
196608          3.75            2031.93         1.00           
196608          3.75            2031.96         1.00           
262144          3.75            2032.15         1.00           
262144          3.75            2031.82         1.00           
393216          3.75            2032.01         1.00           
393216          3.75            2032.15         1.00           
524288          3.75            2032.03         1.00           
524288          3.76            2031.63         1.00           
786432          3.75            2031.84         1.00           
786432          3.75            2031.91         1.00           
1048576         3.76            2031.78         1.00           
1048576         3.75            2031.83         1.00           
1572864         3.76            2031.07         1.00           
1572864         3.76            2031.14         1.00           
2097152         3.76            2030.76         1.00           
2097152         3.76            2030.54         1.00           
3145728         3.76            2029.86         1.00           
3145728         3.77            2023.50         1.00           
4194304         3.78            2016.44         1.00           
4194304         3.78            2016.54         1.00           
6291456         3.83            1993.31         1.01           
6291456         3.83            1994.22         1.00           
8388608         3.84            1988.83         1.00           
8388608         3.84            1988.37         1.00           
12582912        3.84            1986.52         1.00           
12582912        3.84            1986.86         1.00           
16777216        3.85            1979.75         1.00           
16777216        3.84            1986.33         1.00           

                double Write Cache Test

C Size          Nanosec         MB/sec          % Chnge
-------         -------         -------         -------
256             1.26            6042.55         1.00           
256             1.26            6040.44         1.00           
384             1.26            6063.37         1.00           
384             1.26            6063.59         1.00           
512             1.26            6073.30         1.00           
512             1.26            6074.22         1.00           
768             0.96            7920.17         0.77           
768             0.96            7921.69         1.00           
1024            0.93            8197.47         0.97           
1024            0.93            8197.68         1.00           
1536            0.90            8493.55         0.97           
1536            0.90            8493.27         1.00           
2048            0.88            8651.66         0.98           
2048            0.88            8651.29         1.00           
3072            0.87            8813.72         0.98           
3072            0.87            8813.70         1.00           
4096            0.86            8896.61         0.99           
4096            0.86            8897.41         1.00           
6144            0.85            8982.53         0.99           
6144            0.85            8984.13         1.00           
8192            0.85            8988.53         1.00           
8192            0.85            9026.08         1.00           
12288           0.84            9069.26         1.00           
12288           0.84            9070.03         1.00           
16384           0.84            9091.72         1.00           
16384           0.84            9092.04         1.00           
24576           0.84            9086.20         1.00           
24576           0.84            9113.88         1.00           
32768           0.84            9124.38         1.00           
32768           0.84            9124.01         1.00           
49152           0.84            9135.65         1.00           
49152           0.83            9137.08         1.00           
65536           0.83            9141.01         1.00           
65536           0.83            9141.54         1.00           
98304           0.83            9146.49         1.00           
98304           0.84            9114.36         1.00           
131072          0.83            9149.46         1.00           
131072          0.83            9150.82         1.00           
196608          0.83            9152.17         1.00           
196608          0.83            9150.87         1.00           
262144          0.83            9153.54         1.00           
262144          0.83            9153.42         1.00           
393216          0.83            9154.30         1.00           
393216          0.83            9155.94         1.00           
524288          0.83            9154.90         1.00           
524288          0.83            9155.41         1.00           
786432          0.83            9154.75         1.00           
786432          0.83            9156.89         1.00           
1048576         0.84            9135.19         1.00           
1048576         0.84            9135.87         1.00           
1572864         0.85            9027.86         1.01           
1572864         0.85            9027.23         1.00           
2097152         0.85            8989.68         1.00           
2097152         0.85            9022.11         1.00           
3145728         0.86            8882.21         1.02           
3145728         0.86            8861.15         1.00           
4194304         1.32            5798.98         1.53           
4194304         1.31            5805.26         1.00           
6291456         2.36            3239.06         1.79           
6291456         2.35            3242.85         1.00           
8388608         2.83            2698.66         1.20           
8388608         2.82            2704.82         1.00           
12582912        3.06            2496.80         1.08           
12582912        3.05            2500.96         1.00           
16777216        3.09            2465.28         1.01           
16777216        3.09            2466.29         1.00           

                double RMW Cache Test

C Size          Nanosec         MB/sec          % Chnge
-------         -------         -------         -------
256             0.62            12209.84        1.00           
256             0.62            12212.67        1.00           
384             0.62            12211.04        1.00           
384             0.62            12208.95        1.00           
512             0.62            12211.87        1.00           
512             0.62            12210.71        1.00           
768             0.48            15825.75        0.77           
768             0.50            15349.91        1.03           
1024            0.48            15759.09        0.97           
1024            0.51            14929.36        1.06           
1536            0.47            16300.53        0.92           
1536            0.45            17021.14        0.96           
2048            0.44            17331.27        0.98           
2048            0.48            15900.51        1.09           
3072            0.46            16591.49        0.96           
3072            0.44            17326.56        0.96           
4096            0.43            17811.72        0.97           
4096            0.43            17812.72        1.00           
6144            0.42            17976.43        0.99           
6144            0.42            17977.75        1.00           
8192            0.47            16065.23        1.12           
8192            0.43            17915.50        0.90           
12288           0.43            17551.04        1.02           
12288           0.44            17420.38        1.01           
16384           0.42            18185.73        0.96           
16384           0.42            18142.81        1.00           
24576           0.47            16246.48        1.12           
24576           0.42            18210.98        0.89           
32768           0.46            16532.44        1.10           
32768           0.42            18166.19        0.91           
49152           0.43            17571.23        1.03           
49152           0.44            17201.28        1.02           
65536           0.43            17799.25        0.97           
65536           0.44            17513.32        1.02           
98304           0.46            16514.74        1.06           
98304           0.42            18140.35        0.91           
131072          0.42            18162.94        1.00           
131072          0.45            16904.79        1.07           
196608          0.42            18172.95        0.93           
196608          0.43            17702.74        1.03           
262144          0.46            16730.77        1.06           
262144          0.44            17254.95        0.97           
393216          0.42            18181.15        0.95           
393216          0.42            18129.23        1.00           
524288          0.45            17125.48        1.06           
524288          0.43            17891.14        0.96           
786432          0.42            18181.77        0.98           
786432          0.43            17932.65        1.01           
1048576         0.44            17260.01        1.04           
1048576         0.43            17873.87        0.97           
1572864         0.46            16603.70        1.08           
1572864         0.45            16825.95        0.99           
2097152         0.46            16720.90        1.01           
2097152         0.46            16440.88        1.02           
3145728         0.46            16414.83        1.00           
3145728         0.44            17182.97        0.96           
4194304         0.68            11185.53        1.54           
4194304         0.67            11419.15        0.98           
6291456         1.20            6360.79         1.80           
6291456         1.20            6377.23         1.00           
8388608         1.45            5274.40         1.21           
8388608         1.45            5272.67         1.00           
12582912        1.56            4877.82         1.08           
12582912        1.56            4879.69         1.00           
16777216        1.58            4821.30         1.01           
16777216        1.58            4816.21         1.00           



Using the program bandwidth, the measurements are:

# ./bandwidth64
This is bandwidth version 0.16.
Copyright (C) 2005,2007-2009 by Zack T Smith.

This software is covered by the GNU Public License.
It is provided AS-IS, use at your own risk.
See the file COPYING for more information.

Using 64- and 128-bit data transfers.

CPU speed is 2403 MHz.
L1 theoretical max is 19224 MB/second (one 64-bit access/cycle).

Sequential read (64-bit, size=256, loops = 4194304) 18281.1 MB/sec 
Sequential read (64-bit, size=512, loops = 2097152) 18303.4 MB/sec 
Sequential read (64-bit, size=1024, loops = 1048576) 18302.7 MB/sec 
Sequential read (64-bit, size=2048, loops = 524288) 18304.7 MB/sec 
Sequential read (64-bit, size=4096, loops = 262144) 18297.8 MB/sec 
Sequential read (64-bit, size=8192, loops = 131072) 18300.4 MB/sec 
Sequential read (64-bit, size=16384, loops = 65536) 18300.7 MB/sec 
Sequential read (64-bit, size=32768, loops = 32768) 17858.1 MB/sec 
Sequential read (64-bit, size=65536, loops = 16384) 13575.7 MB/sec 
Sequential read (64-bit, size=131072, loops = 8192) 13600.7 MB/sec 
Sequential read (64-bit, size=262144, loops = 4096) 13593 MB/sec 
Sequential read (64-bit, size=524288, loops = 2048) 13590.5 MB/sec 
Sequential read (64-bit, size=1048576, loops = 1024) 13599.5 MB/sec 
Sequential read (64-bit, size=2097152, loops = 512) 13474.9 MB/sec 
Sequential read (64-bit, size=4194304, loops = 256) 8104.54 MB/sec 
Sequential read (64-bit, size=8388608, loops = 128) 5359.15 MB/sec 
Sequential read (64-bit, size=16777216, loops = 64) 5037.86 MB/sec 

Sequential write (64-bit, size=256, loops = 4194304) 17747.6 MB/sec 
Sequential write (64-bit, size=512, loops = 2097152) 17747 MB/sec 
Sequential write (64-bit, size=1024, loops = 1048576) 17693 MB/sec 
Sequential write (64-bit, size=2048, loops = 524288) 17738.4 MB/sec 
Sequential write (64-bit, size=4096, loops = 262144) 17747.9 MB/sec 
Sequential write (64-bit, size=8192, loops = 131072) 17741.4 MB/sec 
Sequential write (64-bit, size=16384, loops = 65536) 17739.3 MB/sec 
Sequential write (64-bit, size=32768, loops = 32768) 17678.3 MB/sec 
Sequential write (64-bit, size=65536, loops = 16384) 11491.5 MB/sec 
Sequential write (64-bit, size=131072, loops = 8192) 11499.9 MB/sec 
Sequential write (64-bit, size=262144, loops = 4096) 11494.9 MB/sec 
Sequential write (64-bit, size=524288, loops = 2048) 11505.1 MB/sec 
Sequential write (64-bit, size=1048576, loops = 1024) 11913.1 MB/sec 
Sequential write (64-bit, size=2097152, loops = 512) 10521.3 MB/sec 
Sequential write (64-bit, size=4194304, loops = 256) 5929.15 MB/sec 
Sequential write (64-bit, size=8388608, loops = 128) 2696.65 MB/sec 
Sequential write (64-bit, size=16777216, loops = 64) 2457.62 MB/sec 

Sequential read (128-bit, size=256, loops = 4194304) 36562.3 MB/sec 
Sequential read (128-bit, size=512, loops = 2097152) 36606.7 MB/sec 
Sequential read (128-bit, size=1024, loops = 1048576) 36605.4 MB/sec 
Sequential read (128-bit, size=2048, loops = 524288) 36606.7 MB/sec 
Sequential read (128-bit, size=4096, loops = 262144) 36604.1 MB/sec 
Sequential read (128-bit, size=8192, loops = 131072) 36606.7 MB/sec 
Sequential read (128-bit, size=16384, loops = 65536) 36605.4 MB/sec 
Sequential read (128-bit, size=32768, loops = 32768) 34464.2 MB/sec 
Sequential read (128-bit, size=65536, loops = 16384) 16964.6 MB/sec 
Sequential read (128-bit, size=131072, loops = 8192) 16974.7 MB/sec 
Sequential read (128-bit, size=262144, loops = 4096) 16950.8 MB/sec 
Sequential read (128-bit, size=524288, loops = 2048) 16916.4 MB/sec 
Sequential read (128-bit, size=1048576, loops = 1024) 16886 MB/sec 
Sequential read (128-bit, size=2097152, loops = 512) 17404.3 MB/sec 
Sequential read (128-bit, size=4194304, loops = 256) 10495.9 MB/sec 
Sequential read (128-bit, size=8388608, loops = 128) 5865.47 MB/sec 
Sequential read (128-bit, size=16777216, loops = 64) 5442.99 MB/sec 

Sequential write (128-bit (bypasses caches), size=256, loops = 4194304) 3745.58 MB/sec 
Sequential write (128-bit (bypasses caches), size=4096, loops = 262144) 4645.15 MB/sec 
Sequential write (128-bit (bypasses caches), size=65536, loops = 16384) 4644.14 MB/sec 
Sequential write (128-bit (bypasses caches), size=1048576, loops = 1024) 4640.56 MB/sec 
Sequential write (128-bit (bypasses caches), size=16777216, loops = 64) 4638.88 MB/sec 


Framebuffer resolution: 1024x768, 16bpp
Framebuffer memory sequential read 11.0282 MB/sec 
Framebuffer memory sequential write 271.02 MB/sec 

Library: memset 4510.88 MB/sec 
Library: memcpy 2481.12 MB/sec 

Performance of my_bzeroSSE2: 4635.55 MB/sec