Snapshot Speed Problem

Hi all,

if we make a snapshot ov a VM/CT we have very slow speed.
If we do start a hdd speedtest, we have over 500mb/s. We have test it on a modular server and on a hp blade server. We have test it with small vm´s/ct´s and with big vm´s/ct´s -> smae issue. Do you have a idea to fix it or what we can do to have a faster speed on backup vm´s/ct´s?

Very thanks.

regards