>> Unless you do a shrink on the vmdk and use a zfs variant with scsi unmap
>> support (I believe currently only Nexenta but correct me if I am wrong) the
>> blocks will not be freed, will they?
> Solaris 11.1 has ZFS with SCSI UNMAP support.
Freeing unused blocks works perfectly well with fstrim (Linux)
consuming an iSCSI zvol served up by oi151a6.
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