qemu-img convert: use cache=none

this fixes an issue with zvols, which require cache=none and eat up all
free memory as buffered pages otherwise

https://github.com/zfsonlinux/zfs/issues/7235

Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>

diff --git a/PVE/QemuServer.pm b/PVE/QemuServer.pm
index 061effa9ea7c71f2aa96aa81a4f9c2b29c24384b..91a2bfc861524ea14af869cae9bee4c420f1a365 100644 (file)
--- a/PVE/QemuServer.pm
+++ b/PVE/QemuServer.pm
@@ -6146,6 +6146,7 @@ sub qemu_img_convert {
        my $cmd = [];
        push @$cmd, '/usr/bin/qemu-img', 'convert', '-p', '-n';
        push @$cmd, '-s', $snapname if($snapname && $src_format eq "qcow2");
+       push @$cmd, '-t', 'none', '-T', 'none';
        push @$cmd, '-f', $src_format, '-O', $dst_format, $src_path;
        if ($is_zero_initialized) {
            push @$cmd, "zeroinit:$dst_path";