LVM2 snapshot performance problems

http://www.nikhef.nl/~dennisvd/lvmcrap.html

it is a feature that needs to be used with care, because it has definitive performance issues.
(中略)

sync ; time sh -c "dd if=/dev/zero of=asdf bs=1M count=1000 ; sync"

Test on un-snapshotted disk:

5s

Test on the snapshotted disk:

512k   55s
256k   49s
128k   49s
 64k   83s
 32k   63s
 16k  200s
  8k  304s
  4k  625s

When I did a test on the live server with the 512k chunk size, the server froze solid and was reset by the hardware watchdog.
(中略)

素敵〜、めも