Hi,
I'm having troubles at the first step: determining the erase block size. The strange results are below. The original FAT layout was not saved when the drive was purchased.
# lsusb Bus 004 Device 002: ID 125f:c82a A-DATA Technology Co., Ltd.
# fdisk -l /dev/disk/by-id/usb-ADATA_USB_Flash_Drive_1061309422330015-0:0
Disk /dev/disk/by-id/usb-ADATA_USB_Flash_Drive_1061309422330015-0:0: 7873 MB, 7873757184 bytes 180 heads, 14 sectors/track, 6102 cylinders, total 15378432 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0xf65985aa
Device Boot Start End Blocks Id System /dev/disk/by-id/usb-ADATA_USB_Flash_Drive_1061309422330015-0:0-part1 2048 15378431 7688192 83 Linux
# for i in 1 2 4 8 16; do echo -e "\n\nbs=$[$i*1024]"; flashbench -a /dev/disk/by-id/usb-ADATA_USB_Flash_Drive_1061309422330015-0:0 --blocksize=$[$i*1024]; done
bs=1024 align 2147483648 pre 829µs on 815µs post 836µs diff -17473n align 1073741824 pre 846µs on 796µs post 853µs diff -53379n align 536870912 pre 744µs on 781µs post 834µs diff -8238ns align 268435456 pre 827µs on 798µs post 831µs diff -31049n align 134217728 pre 758µs on 763µs post 763µs diff 2.71µs align 67108864 pre 789µs on 779µs post 815µs diff -22737n align 33554432 pre 773µs on 747µs post 779µs diff -29372n align 16777216 pre 695µs on 773µs post 816µs diff 16.8µs align 8388608 pre 688µs on 728µs post 691µs diff 39µs align 4194304 pre 733µs on 779µs post 815µs diff 4.47µs align 2097152 pre 742µs on 761µs post 759µs diff 10.8µs align 1048576 pre 811µs on 793µs post 817µs diff -21380n align 524288 pre 799µs on 794µs post 816µs diff -13187n align 262144 pre 756µs on 795µs post 800µs diff 17µs align 131072 pre 737µs on 685µs post 744µs diff -55710n align 65536 pre 741µs on 747µs post 747µs diff 3.18µs align 32768 pre 798µs on 780µs post 799µs diff -18178n align 16384 pre 732µs on 779µs post 796µs diff 15.1µs align 8192 pre 740µs on 776µs post 799µs diff 7.01µs align 4096 pre 952µs on 758µs post 799µs diff -117830 align 2048 pre 738µs on 774µs post 798µs diff 6.04µs
bs=2048 align 2147483648 pre 853µs on 848µs post 869µs diff -12804n align 1073741824 pre 861µs on 869µs post 869µs diff 3.88µs align 536870912 pre 833µs on 834µs post 835µs diff -193ns align 268435456 pre 877µs on 907µs post 900µs diff 18.4µs align 134217728 pre 842µs on 851µs post 870µs diff -5455ns align 67108864 pre 828µs on 799µs post 833µs diff -31688n align 33554432 pre 767µs on 827µs post 832µs diff 26.9µs align 16777216 pre 758µs on 776µs post 762µs diff 16.2µs align 8388608 pre 713µs on 714µs post 712µs diff 868ns align 4194304 pre 857µs on 887µs post 866µs diff 25.9µs align 2097152 pre 837µs on 867µs post 872µs diff 12.7µs align 1048576 pre 847µs on 834µs post 847µs diff -13895n align 524288 pre 865µs on 882µs post 866µs diff 16.4µs align 262144 pre 864µs on 849µs post 868µs diff -17470n align 131072 pre 795µs on 799µs post 799µs diff 1.98µs align 65536 pre 868µs on 868µs post 867µs diff 205ns align 32768 pre 866µs on 867µs post 868µs diff -623ns align 16384 pre 859µs on 853µs post 871µs diff -11754n align 8192 pre 859µs on 869µs post 849µs diff 15µs align 4096 pre 978µs on 980µs post 829µs diff 76.4µs
bs=4096 align 2147483648 pre 905µs on 908µs post 1.05ms diff -70516n align 1073741824 pre 997µs on 979µs post 1.11ms diff -72729n align 536870912 pre 961µs on 978µs post 1.1ms diff -51399n align 268435456 pre 965µs on 973µs post 1.07ms diff -42441n align 134217728 pre 890µs on 891µs post 1.03ms diff -70698n align 67108864 pre 855µs on 838µs post 1.02ms diff -97971n align 33554432 pre 853µs on 870µs post 1.05ms diff -80043n align 16777216 pre 832µs on 832µs post 1.03ms diff -98061n align 8388608 pre 842µs on 843µs post 1.03ms diff -92877n align 4194304 pre 933µs on 960µs post 1.08ms diff -46878n align 2097152 pre 924µs on 926µs post 1.03ms diff -51066n align 1048576 pre 948µs on 925µs post 1.07ms diff -82986n align 524288 pre 970µs on 981µs post 1.1ms diff -55840n align 262144 pre 985µs on 954µs post 1.12ms diff -97010n align 131072 pre 933µs on 944µs post 1.08ms diff -60718n align 65536 pre 970µs on 956µs post 1.03ms diff -46152n align 32768 pre 963µs on 943µs post 1.11ms diff -91246n align 16384 pre 914µs on 924µs post 1.07ms diff -67228n align 8192 pre 923µs on 924µs post 1.09ms diff -80328n
bs=8192 align 2147483648 pre 1.66ms on 1.62ms post 1.64ms diff -29621n align 1073741824 pre 1.65ms on 1.64ms post 1.68ms diff -22022n align 536870912 pre 1.62ms on 1.62ms post 1.62ms diff 662ns align 268435456 pre 1.62ms on 1.6ms post 1.62ms diff -17675n align 134217728 pre 1.64ms on 1.61ms post 1.64ms diff -31935n align 67108864 pre 1.68ms on 1.67ms post 1.67ms diff -3326ns align 33554432 pre 1.73ms on 1.74ms post 1.74ms diff 9.42µs align 16777216 pre 1.66ms on 1.64ms post 1.64ms diff -7797ns align 8388608 pre 1.65ms on 1.66ms post 1.65ms diff 8.27µs align 4194304 pre 1.63ms on 1.65ms post 1.65ms diff 10.3µs align 2097152 pre 1.62ms on 1.64ms post 1.64ms diff 6.62µs align 1048576 pre 1.66ms on 1.66ms post 1.65ms diff 2.68µs align 524288 pre 1.66ms on 1.64ms post 1.64ms diff -6934ns align 262144 pre 1.65ms on 1.66ms post 1.66ms diff 197ns align 131072 pre 1.64ms on 1.64ms post 1.64ms diff 1.64µs align 65536 pre 1.65ms on 1.62ms post 1.62ms diff -12165n align 32768 pre 1.66ms on 1.66ms post 1.67ms diff -9644ns align 16384 pre 1.62ms on 1.62ms post 1.64ms diff -9352ns
bs=16384 align 2147483648 pre 2.39ms on 2.35ms post 2.33ms diff -7216ns align 1073741824 pre 2.46ms on 2.44ms post 2.43ms diff 341ns align 536870912 pre 2.28ms on 2.28ms post 2.28ms diff -1850ns align 268435456 pre 2.32ms on 2.28ms post 2.3ms diff -29446n align 134217728 pre 2.3ms on 2.32ms post 2.32ms diff 7.53µs align 67108864 pre 2.32ms on 2.31ms post 2.3ms diff 2.12µs align 33554432 pre 2.38ms on 2.41ms post 2.43ms diff 4µs align 16777216 pre 2.32ms on 2.28ms post 2.27ms diff -7553ns align 8388608 pre 2.28ms on 2.28ms post 2.29ms diff -6386ns align 4194304 pre 2.28ms on 2.28ms post 2.28ms diff -1055ns align 2097152 pre 2.28ms on 2.26ms post 2.28ms diff -18798n align 1048576 pre 2.28ms on 2.28ms post 2.26ms diff 9.31µs align 524288 pre 2.33ms on 2.32ms post 2.32ms diff -4279ns align 262144 pre 2.29ms on 2.28ms post 2.25ms diff 8.77µs align 131072 pre 2.3ms on 2.26ms post 2.3ms diff -35064n align 65536 pre 2.31ms on 2.27ms post 2.28ms diff -33000n align 32768 pre 2.3ms on 2.31ms post 2.34ms diff -730ns
# flashbench -a /dev/disk/by-id/usb-ADATA_USB_Flash_Drive_1061309422330015-0:0 --blocksize=$[10*1024] align 1342177280 pre 1.66ms on 2.14ms post 1.69ms diff 465µs align 671088640 pre 1.66ms on 2.16ms post 1.66ms diff 499µs align 335544320 pre 1.69ms on 2.19ms post 1.71ms diff 493µs align 167772160 pre 1.76ms on 2.26ms post 1.75ms diff 510µs align 83886080 pre 1.62ms on 2.09ms post 1.67ms diff 447µs align 41943040 pre 1.8ms on 2.33ms post 1.76ms diff 551µs align 20971520 pre 1.62ms on 2.12ms post 1.64ms diff 490µs align 10485760 pre 1.64ms on 2.1ms post 1.65ms diff 455µs align 5242880 pre 1.62ms on 2.08ms post 1.68ms diff 432µs align 2621440 pre 1.65ms on 2.12ms post 1.68ms diff 456µs align 1310720 pre 1.6ms on 2.03ms post 1.55ms diff 450µs align 655360 pre 1.57ms on 2.03ms post 1.62ms diff 437µs align 327680 pre 1.66ms on 2.08ms post 1.64ms diff 435µs align 163840 pre 1.63ms on 2.06ms post 1.62ms diff 436µs align 81920 pre 1.64ms on 2.08ms post 1.64ms diff 447µs align 40960 pre 1.66ms on 2.19ms post 1.73ms diff 499µs align 20480 pre 2.07ms on 1.64ms post 1.66ms diff -226664
On Tuesday 05 February 2013, Csordás Csaba Ifj. wrote:
Hi,
I'm having troubles at the first step: determining the erase block size. The strange results are below. The original FAT layout was not saved when the drive was purchased.
# lsusb Bus 004 Device 002: ID 125f:c82a A-DATA Technology Co., Ltd.
# fdisk -l /dev/disk/by-id/usb-ADATA_USB_Flash_Drive_1061309422330015-0:0
Disk /dev/disk/by-id/usb-ADATA_USB_Flash_Drive_1061309422330015-0:0: 7873 MB, 7873757184 bytes 180 heads, 14 sectors/track, 6102 cylinders, total 15378432 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0xf65985aa
Device Boot Start End Blocks Id System/dev/disk/by-id/usb-ADATA_USB_Flash_Drive_1061309422330015-0:0-part1 2048 15378431 7688192 83 Linux
The size is a multiple of three, so you might want to retry with
# for i in 1 2 4 8 16; do echo -e "\n\nbs=$[$i*1024]"; flashbench -a /dev/disk/by-id/usb-ADATA_USB_Flash_Drive_1061309422330015-0:0 --blocksize=$[$i*1024]; done
--blocksize=3072.
If that does not help, you can run the other tests after guessing an erase block size, because sometimes the -a test does not reveal anything at all.
My first guess for this device would be a 6 MB erase block size, followed by 8 MB, 12 MB, and 4 MB.
Arnd
Hi,
I'm really sorry for the really-really long time I haven't answered.
Here are some other results, these were run 1 month ago. Quite unreadable for me. I will write an awk script and redo the tests, and put the results on https://gist.github.com/. Or somewhere else you would like to.
And thank you for your previous comment.
flashbench -a /dev/disk/by-id/usb-ADATA_USB_Flash_Drive_1061309422330015-0:0 --blocksize=3072 --count=100 align 1610612736 pre 791µs on 810µs post 804µs diff 12.8µs align 805306368 pre 740µs on 742µs post 759µs diff -7482ns align 402653184 pre 755µs on 770µs post 756µs diff 14.2µs align 201326592 pre 654µs on 683µs post 651µs diff 30.4µs align 100663296 pre 669µs on 687µs post 669µs diff 18.2µs align 50331648 pre 668µs on 685µs post 667µs diff 17.3µs align 25165824 pre 653µs on 649µs post 649µs diff -1336ns align 12582912 pre 634µs on 649µs post 633µs diff 15.3µs align 6291456 pre 670µs on 685µs post 672µs diff 13.6µs align 3145728 pre 760µs on 757µs post 758µs diff -1894ns align 1572864 pre 746µs on 757µs post 741µs diff 13µs align 786432 pre 744µs on 783µs post 743µs diff 39.4µs align 393216 pre 760µs on 773µs post 757µs diff 15.1µs align 196608 pre 804µs on 820µs post 805µs diff 15.1µs align 98304 pre 705µs on 701µs post 704µs diff -4015ns align 49152 pre 802µs on 801µs post 800µs diff -262ns align 24576 pre 721µs on 748µs post 732µs diff 21.9µs align 12288 pre 931µs on 837µs post 699µs diff 21.5µs align 6144 pre 942µs on 727µs post 764µs diff -125934
--erasesize=$[6* 1024 * 1024] --blocksize=$[3*1024] --count=100
oau=2 6MiB 3.25M/s 3MiB 3.2M/s 1.5MiB 2.2M/s 768KiB 2.14M/s 384KiB 2.07M/s 192KiB 2.03M/s 96KiB 1.91M/s 48KiB 1.58M/s 24KiB 1.34M/s 12KiB 834K/s 6KiB 479K/s 3KiB 286K/s
oau=2 random 6MiB 2.86M/s 3MiB 1.78M/s 1.5MiB 1.98M/s 768KiB 1.35M/s 384KiB 470K/s 192KiB 286K/s 96KiB 181K/s 48KiB 2.78M/s 24KiB 653K/s 12KiB 88.9K/s 6KiB 57.9K/s 3KiB 157K/s
oau=3 6MiB 3.53M/s 3MiB 3.95M/s 1.5MiB 2.86M/s 768KiB 2.76M/s 384KiB 2.65M/s 192KiB 2.57M/s 96KiB 2.4M/s 48KiB 2M/s 24KiB 1.56M/s 12KiB 798K/s 6KiB 390K/s 3KiB 257K/s
oau=3 random 6MiB 2.56M/s 3MiB 1.79M/s 1.5MiB 1.67M/s 768KiB 1.17M/s 384KiB 441K/s 192KiB 262K/s 96KiB 162K/s 48KiB 2.76M/s 24KiB 213K/s 12KiB 77.2K/s 6KiB 37.8K/s 3KiB 98.2K/s
oau=4 6MiB 3.82M/s 3MiB 4M/s 1.5MiB 3.13M/s 768KiB 3.04M/s 384KiB 2.9M/s 192KiB 2.76M/s 96KiB 2.22M/s 48KiB 1.65M/s 24KiB 1.1M/s 12KiB 1.02M/s 6KiB 420K/s 3KiB 233K/s
oau=4 random 6MiB 2.55M/s 3MiB 1.61M/s 1.5MiB 1.31M/s 768KiB 611K/s 384KiB 331K/s 192KiB 164K/s 96KiB 110K/s 48KiB 819K/s 24KiB 126K/s 12KiB 55.6K/s 6KiB 27.9K/s 3KiB 65.3K/s
oau=5 6MiB 3.97M/s 3MiB 4.15M/s 1.5MiB 2.79M/s 768KiB 2.71M/s 384KiB 2.59M/s 192KiB 2.48M/s 96KiB 1.26M/s 48KiB 1.52M/s 24KiB 1.3M/s 12KiB 848K/s 6KiB 362K/s 3KiB 191K/s
oau=5 random 6MiB 2.63M/s 3MiB 1.57M/s 1.5MiB 1.36M/s 768KiB 642K/s 384KiB 349K/s 192KiB 174K/s 96KiB 115K/s 48KiB 259K/s 24KiB 91.9K/s 12KiB 43.6K/s 6KiB 25.2K/s 3KiB 7.5K/s
oau=6 6MiB 2.98M/s 3MiB 1.62M/s 1.5MiB 1.11M/s 768KiB 619K/s 384KiB 343K/s 192KiB 178K/s 96KiB 62.6K/s 48KiB 63.4K/s 24KiB 31.9K/s 12KiB 16K/s 6KiB 8.05K/s 3KiB 170K/s
oau=6 random 6MiB 2.99M/s 3MiB 1.68M/s 1.5MiB 1.4M/s 768KiB 757K/s 384KiB 412K/s 192KiB 213K/s 96KiB 149K/s 48KiB 137K/s 24KiB 71K/s 12KiB 21.1K/s 6KiB 6.42K/s 3KiB 6.84K/s
--erasesize=$[8* 1024 * 1024] --blocksize=$[4*1024] --count=100
oau=2 8MiB 4.57M/s 4MiB 4.56M/s 2MiB 2.98M/s 1MiB 2.98M/s 512KiB 2.83M/s 256KiB 2.73M/s 128KiB 2.58M/s 64KiB 2.18M/s 32KiB 1.9M/s 16KiB 1.22M/s 8KiB 594K/s 4KiB 342K/s
oau=2 random 8MiB 3.96M/s 4MiB 2.64M/s 2MiB 2.85M/s 1MiB 1.37M/s 512KiB 738K/s 256KiB 374K/s 128KiB 194K/s 64KiB 1.99M/s 32KiB 417K/s 16KiB 63.5K/s 8KiB 38.7K/s 4KiB 147K/s
oau=3 8MiB 4.45M/s 4MiB 4.51M/s 2MiB 3.3M/s 1MiB 3.3M/s 512KiB 3.18M/s 256KiB 3.04M/s 128KiB 2.7M/s 64KiB 1.53M/s 32KiB 2.28M/s 16KiB 1.13M/s 8KiB 567K/s 4KiB 292K/s
oau=3 random 8MiB 3.72M/s 4MiB 2.66M/s 2MiB 2.19M/s 1MiB 1.35M/s 512KiB 739K/s 256KiB 372K/s 128KiB 194K/s 64KiB 2.01M/s 32KiB 140K/s 16KiB 62.3K/s 8KiB 31.8K/s 4KiB 103K/s
oau=4 8MiB 4.19M/s 4MiB 4.47M/s 2MiB 3.54M/s 1MiB 3.51M/s 512KiB 3.42M/s 256KiB 1.58M/s 128KiB 2.92M/s 64KiB 1.77M/s 32KiB 1.39M/s 16KiB 1.24M/s 8KiB 525K/s 4KiB 256K/s
oau=4 random 8MiB 3.61M/s 4MiB 2.34M/s 2MiB 1.81M/s 1MiB 879K/s 512KiB 520K/s 256KiB 247K/s 128KiB 162K/s 64KiB 1.57M/s 32KiB 103K/s 16KiB 40.8K/s 8KiB 24.7K/s 4KiB 70.4K/s
oau=5 8MiB 4.44M/s 4MiB 4.45M/s 2MiB 3.68M/s 1MiB 3.2M/s 512KiB 1.76M/s 256KiB 2.91M/s 128KiB 2.73M/s 64KiB 1.73M/s 32KiB 1.32M/s 16KiB 1.14M/s 8KiB 472K/s 4KiB 216K/s
oau=5 random 8MiB 3.72M/s 4MiB 2.3M/s 2MiB 1.92M/s 1MiB 891K/s 512KiB 492K/s 256KiB 224K/s 128KiB 196K/s 64KiB 267K/s 32KiB 113K/s 16KiB 43.3K/s 8KiB 23.8K/s 4KiB 53.5K/s
--erasesize=$[12* 1024 * 1024] --blocksize=$[3*1024] --count=100
oau=2 12MiB 3.94M/s 6MiB 3.99M/s 3MiB 4M/s 1.5MiB 3.06M/s 768KiB 3.01M/s 384KiB 2.91M/s 192KiB 2.82M/s 96KiB 2.6M/s 48KiB 2.03M/s 24KiB 1.63M/s 12KiB 1.04M/s 6KiB 397K/s 3KiB 291K/s
oau=2 random 12MiB 3.72M/s 6MiB 3.19M/s 3MiB 2.09M/s 1.5MiB 2.71M/s 768KiB 1.75M/s 384KiB 841K/s 192KiB 542K/s 96KiB 522K/s 48KiB 441K/s 24KiB 139K/s 12KiB 60.6K/s 6KiB 27.6K/s 3KiB 60.5K/s
oau=3 12MiB 3.2M/s 6MiB 4.51M/s 3MiB 4.52M/s 1.5MiB 3.65M/s 768KiB 3.59M/s 384KiB 3.45M/s 192KiB 3.29M/s 96KiB 3.03M/s 48KiB 2.35M/s 24KiB 1.74M/s 12KiB 1.01M/s 6KiB 332K/s 3KiB 255K/s
oau=3 random 12MiB 3.65M/s 6MiB 3.16M/s 3MiB 2.06M/s 1.5MiB 2.71M/s 768KiB 1.93M/s 384KiB 911K/s 192KiB 551K/s 96KiB 272K/s 48KiB 339K/s 24KiB 68.2K/s 12KiB 25.7K/s 6KiB 18.9K/s 3KiB 14.2K/s
oau=4 12MiB 4.14M/s 6MiB 4.14M/s 3MiB 4.26M/s 1.5MiB 4.18M/s 768KiB 4.12M/s 384KiB 3.98M/s 192KiB 3.78M/s 96KiB 2.04M/s 48KiB 2.09M/s 24KiB 1.68M/s 12KiB 1.17M/s 6KiB 325K/s 3KiB 228K/s
oau=4 random 12MiB 3.71M/s 6MiB 3.19M/s 3MiB 1.99M/s 1.5MiB 1.52M/s 768KiB 934K/s 384KiB 778K/s 192KiB 312K/s 96KiB 156K/s 48KiB 83.4K/s 24KiB 55.3K/s 12KiB 32.6K/s 6KiB 16.4K/s 3KiB 11.5K/s
oau=5 12MiB 3.62M/s 6MiB 3.14M/s 3MiB 3.75M/s 1.5MiB 3.74M/s 768KiB 3.67M/s 384KiB 3.54M/s 192KiB 3.38M/s 96KiB 1.74M/s 48KiB 1.89M/s 24KiB 1.55M/s 12KiB 1.03M/s 6KiB 307K/s 3KiB 191K/s
oau=5 random 12MiB 3.82M/s 6MiB 3.05M/s 3MiB 2.07M/s 1.5MiB 1.55M/s 768KiB 981K/s 384KiB 558K/s 192KiB 206K/s 96KiB 160K/s 48KiB 77.4K/s 24KiB 44.7K/s 12KiB 17.9K/s 6KiB 10.3K/s ^C
--erasesize=$[4* 1024 * 1024] --blocksize=$[4*1024] --count=100
oau=2 4MiB 4.04M/s 2MiB 3.13M/s 1MiB 3.13M/s 512KiB 3M/s 256KiB 2.91M/s 128KiB 2.75M/s 64KiB 2.41M/s 32KiB 2.3M/s 16KiB 1.05M/s 8KiB 762K/s 4KiB 384K/s
oau=2 random 4MiB 2.6M/s 2MiB 2.5M/s 1MiB 2.32M/s 512KiB 989K/s 256KiB 562K/s 128KiB 260K/s 64KiB 2.04M/s 32KiB 2.26M/s 16KiB 209K/s 8KiB 81.5K/s 4KiB 245K/s
oau=3 4MiB 2.96M/s 2MiB 3.37M/s 1MiB 3.43M/s 512KiB 3.3M/s 256KiB 3.12M/s 128KiB 2.88M/s 64KiB 2.58M/s 32KiB 2.23M/s 16KiB 1.01M/s 8KiB 822K/s 4KiB 315K/s
oau=3 random 4MiB 3.02M/s 2MiB 2.94M/s 1MiB 2.74M/s 512KiB 1.32M/s 256KiB 782K/s 128KiB 375K/s 64KiB 2.23M/s 32KiB 2.25M/s 16KiB 110K/s 8KiB 52.9K/s 4KiB 204K/s
oau=4 4MiB 2.41M/s 2MiB 3.37M/s 1MiB 3.32M/s 512KiB 3.23M/s 256KiB 3.1M/s 128KiB 2.85M/s 64KiB 2.48M/s 32KiB 1.72M/s 16KiB 1.04M/s 8KiB 857K/s 4KiB 267K/s
oau=4 random 4MiB 3.28M/s 2MiB 3.2M/s 1MiB 3.01M/s 512KiB 1.59M/s 256KiB 975K/s 128KiB 479K/s 64KiB 2.36M/s 32KiB 474K/s 16KiB 154K/s 8KiB 47K/s 4KiB 203K/s
oau=5 4MiB 2.16M/s 2MiB 3.3M/s 1MiB 3.28M/s 512KiB 3.19M/s 256KiB 3.05M/s 128KiB 2.81M/s 64KiB 2.47M/s 32KiB 1.55M/s 16KiB 1.09M/s 8KiB 779K/s 4KiB 242K/s
oau=5 random 4MiB 3.31M/s 2MiB 3.39M/s 1MiB 3.22M/s 512KiB 1.81M/s 256KiB 1.15M/s 128KiB 579K/s 64KiB 1.41M/s 32KiB 365K/s 16KiB 112K/s 8KiB 44.6K/s 4KiB 154K/s
oau=6 4MiB 2.41M/s 2MiB 3.46M/s 1MiB 3.4M/s 512KiB 3.29M/s 256KiB 3.15M/s 128KiB 2.87M/s 64KiB 2.54M/s 32KiB 1.47M/s 16KiB 1.06M/s 8KiB 23.2K/s 4KiB 201K/s
oau=6 random 4MiB 3.56M/s 2MiB 3.49M/s 1MiB 3.36M/s 512KiB 2.01M/s 256KiB 1.3M/s 128KiB 253K/s 64KiB 1.5M/s 32KiB 205K/s 16KiB 80.7K/s 8KiB 39.4K/s 4KiB 131K/s
oau=7 4MiB 3.73M/s 2MiB 1.45M/s 1MiB 695K/s 512KiB 341K/s 256KiB 169K/s 128KiB 83.9K/s 64KiB 2.19M/s 32KiB 1.4M/s 16KiB 52.7K/s 8KiB 5.68K/s 4KiB 201K/s
oau=8 4MiB 3.6M/s 2MiB 1.44M/s 1MiB 695K/s 512KiB 341K/s 256KiB 169K/s 128KiB 83.8K/s 64KiB 1.87M/s 32KiB 1.27M/s 16KiB 13.3K/s 8KiB 5.63K/s 4KiB 190K/s
Csordás Csaba Ifj.
On Mon, Feb 11, 2013 at 3:48 PM, Arnd Bergmann arnd@arndb.de wrote:
On Tuesday 05 February 2013, Csordás Csaba Ifj. wrote:
Hi,
I'm having troubles at the first step: determining the erase block size. The strange results are below. The original FAT layout was not saved when the drive was purchased.
# lsusb Bus 004 Device 002: ID 125f:c82a A-DATA Technology Co., Ltd.
# fdisk -l /dev/disk/by-id/usb-ADATA_USB_Flash_Drive_1061309422330015-0:0
Disk /dev/disk/by-id/usb-ADATA_USB_Flash_Drive_1061309422330015-0:0: 7873 MB, 7873757184 bytes 180 heads, 14 sectors/track, 6102 cylinders, total 15378432 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0xf65985aa
Device Boot Start End Blocks Id System/dev/disk/by-id/usb-ADATA_USB_Flash_Drive_1061309422330015-0:0-part1 2048 15378431 7688192 83 Linux
The size is a multiple of three, so you might want to retry with
# for i in 1 2 4 8 16; do echo -e "\n\nbs=$[$i*1024]"; flashbench -a /dev/disk/by-id/usb-ADATA_USB_Flash_Drive_1061309422330015-0:0 --blocksize=$[$i*1024]; done
--blocksize=3072.
If that does not help, you can run the other tests after guessing an erase block size, because sometimes the -a test does not reveal anything at all.
My first guess for this device would be a 6 MB erase block size, followed by 8 MB, 12 MB, and 4 MB.
Arnd
On Tue, 5 Feb 2013 22:47:21 +0100 Csordás Csaba Ifj. cscsordas@gmail.com wrote:
I'm having troubles at the first step: determining the erase block size. The strange results are below. The original FAT layout was not saved when the drive was purchased.
The original partition map may not be that helpful anyway.
If you use the --count=N option where N is 128 or so or some other quite large number, you might get better results. The test will take longer as it will run each test N times.
Just run: flashbench -a /dev/disk/by-id/usb-ADATA_USB_Flash_Drive_1061309422330015-0:0 --blocksize=2048 --count=100
It also could be that this device isn't measurable this way.
-Andrew
flashbench-results@lists.linaro.org
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Andrew Bradford -
Arnd Bergmann -
Csordás Csaba Ifj.