Testing hard disk writing speed

time dd if=/dev/zero of=TEST bs=4k count=512000

1
By: flojb
2009-10-17 17:50:53

These Might Interest You


  • 13
    hdparm -t /dev/sda
    bassel · 2009-09-14 21:04:08 2

  • 0
    sync; time `dd if=/dev/zero of=bigfile bs=1M count=2048 && sync`
    w00binda · 2009-11-19 10:29:03 1
  • For disk space constraint testing. Leaves a little space available for creating temp files, etc. Easily free up the used disk space again by deleting the dummy00 file. Can tailor the testing by building smaller 'blocks' to suit the needs of the testing. WARNING: do not do this to the '/' (root) filesystem unless you know what you are doing... on some systems it could crash the OS.


    -3
    dd if=/dev/zero of=/fs/to/fill/dummy00 bs=8192 count=$(df --block-size=8192 / | awk 'NR!=1 {print $4-100}')
    arcege · 2009-12-03 15:20:18 0
  • (WARN) This will absolutely not work on all systems, unless you're running large, high speed, hardware RAID arrays. For example, systems using Dell PERC 5/i SAS/SATA arrays. If you have a hardware RAID array, try it. It certainly wont hurt. You may be can test the speed disk with some large file in your system, before and after using this: time dd if=/tmp/disk.iso of=/dev/null bs=256k To know the value of block device parameter known as readahead. blockdev --getra /dev/sdb And set the a value 1024, 2048, 4096, 8192, and maybe 16384... it really depends on the number of hard disks, their speed, your RAID controller, etc. (see sample) Show Sample Output


    2
    blockdev --setra 1024 /dev/sdb
    starchox · 2009-02-18 16:27:01 1

What Others Think

Use hdparm -t -T /dev/sda to test drive reading speed (through the drive's buffer). Hopefully a decent indicator of writing speed.
bwoodacre · 452 weeks and 6 days ago
Or use a real benchmarking program like bonnie++ to get numbers for other cases than one large sequential file.
hfs · 452 weeks and 2 days ago
use iozone
ioggstream · 452 weeks and 2 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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