Disks and filesystems
- badblocks -v- s /dev/sdb >badblocks.log
- Check a device for bad blocks
- fdisk /dev/sdb
- Manage disk partitions
- df -h
- Show filesystem block usage in human friendly format
- df -i
- Show filesystem inode usage
- ls -i <file>
- Show inode of <file>
- rm -i <file>
- Remove a file by its inode
- mount -t <fstype> -o <options> <devicefile> <mountpoint>
- Mount a filesystem (fstype and options can be omitted often)
- mount -o loop /path/to/my-iso-image.iso /mnt/iso
- Mount an .iso file
Performance
The graphical utility Disks has a benchmark option.
- dd if=/dev/zero of=./test.tmp bs=1G count=1 oflag=dsync;rm -f ./test.tmp
- Plain write speed
- dd if=/dev/zero of=./test.tmp bs=512 count=1000 oflag=dsync;rm -f ./test.tmp
- Latency test
On an empty disk you can do:
- dd if=/dev/zero of=/dev/sdb bs=8k count=10k
- Test disk write speed if no filesystems exists
Misc
- /dev/null
- The unix black hole. Write always succeeds with no effect at all.
- /dev/zero
- Provides an unlimited amount of null characters (ASCII 0). Can be used for cleaning disks or benchmarking (see #Performance)
- Writing to /dev/zero is the same as writing to /dev/null