linux – 快速磁盘克隆

dd if=/dev/sda of=/dev/sdb bs=1M

此外,调整驱动器上的“预读”通常可以提高性能.默认值可能是256,最佳1024.每个设置都不同,因此您必须运行基准测试才能找到最佳值.

# blockdev --getra /dev/sda
256
# blockdev --setra 1024 /dev/sda
# blockdev --getra /dev/sda
1024
# blockdev --Help
Usage:
  blockdev -V
  blockdev --report [devices]
  blockdev [-v|-q] commands devices
Available commands:
    --getsz (get size in 512-byte sectors)
    --setro (set read-only)
    --setrw (set read-writE)
    --getro (get read-only)
    --getss (get sectorsizE)
    --getbsz    (get blocksizE)
    --setbsz BLOCKSIZE  (set blocksizE)
    --getsize   (get 32-bit sector count)
    --getsize64 (get size in bytes)
    --setra READAHEAD   (set readahead)
    --getra (get readahead)
    --flushbufs (flush buffers)
    --rereadpt  (reread partition tablE)
    --rmpart PARTNO (disable partition)
    --rmparts   (disable all partitions)
#