Hi all,
Since a while I've been encountering strange behavior regarding the speed of the virtual disk.
I created a storage pool with LVM-Thin. This is on an SSD.
If I create a new VM and install (for example) Debian on it, nothing out of the ordinairy happens.
I just have disk performances of up to 500 Mb/s and I also get these speeds regularly.
But when I migrate a disk from a ZFS pool, or I change a setting of the disk of the Debian VM just mentioned (for example, I turn on SSD emulation), the performance drops to max 25 Mb/s. Now you will think that if I turn that option off again, and make the configuration is the same as before this problem, the performance should be the same again. But that's not true. It hangs at max 25 Mb/s.
I test the speeds with the same FIO command and any form of caching is disabled.
Any help and tips are welcome.
Since a while I've been encountering strange behavior regarding the speed of the virtual disk.
I created a storage pool with LVM-Thin. This is on an SSD.
If I create a new VM and install (for example) Debian on it, nothing out of the ordinairy happens.
I just have disk performances of up to 500 Mb/s and I also get these speeds regularly.
But when I migrate a disk from a ZFS pool, or I change a setting of the disk of the Debian VM just mentioned (for example, I turn on SSD emulation), the performance drops to max 25 Mb/s. Now you will think that if I turn that option off again, and make the configuration is the same as before this problem, the performance should be the same again. But that's not true. It hangs at max 25 Mb/s.
I test the speeds with the same FIO command and any form of caching is disabled.
Any help and tips are welcome.