calculate reasonable metadatasize for lvm thin pools on creation

Letting LVM set the meta-data size internally was not a good idea, as
it produces really small metadata LVs. Adapts the same logic as the
installer.

Signed-off-by: Tim Marx <t.marx@proxmox.com>
Reviewed-By: Dominik Csapak <d.csapak@proxmox.com>
Tested-By: Dominik Csapak <d.csapak@proxmox.com>

diff --git a/PVE/API2/Disks/LVMThin.pm b/PVE/API2/Disks/LVMThin.pm
index 23c027909512e34d9b1881e1acc7835d307cec81..4d303f8daa89dbb0fdc35ceb8fb29ade1eebe62e 100644 (file)
--- a/PVE/API2/Disks/LVMThin.pm
+++ b/PVE/API2/Disks/LVMThin.pm
@@ -109,9 +109,26 @@ __PACKAGE__->register_method ({
        my $worker = sub {
            PVE::Diskmanage::locked_disk_action(sub {
                PVE::Storage::LVMPlugin::lvm_create_volume_group($dev, $name);
+               my $pv = PVE::Storage::LVMPlugin::lvm_pv_info($dev);
+               # keep some free space just in case
+               my $datasize = $pv->{size} - 128*1024;
+               # default to 1% for metadata
+               my $metadatasize = $datasize/100;
+               # but at least 1G, as recommended in lvmthin man
+               $metadatasize = 1024*1024 if $metadatasize < 1024*1024;
+               # but at most 16G, which is the current lvm max
+               $metadatasize = 16*1024*1024 if $metadatasize > 16*1024*1024;
+               # shrink data by needed amount for metadata
+               $datasize -= 2*$metadatasize;
 
-               # create thinpool with size 100%, let lvm handle the metadata size
-               run_command(['/sbin/lvcreate', '--type', 'thin-pool', '-l100%FREE', '-n', $name, $name]);
+               run_command([
+                   '/sbin/lvcreate',
+                   '--type', 'thin-pool',
+                   "-L${datasize}K",
+                   '--poolmetadatasize', "${metadatasize}K",
+                   '-n', $name,
+                   $name
+               ]);
 
                if ($param->{add_storage}) {
                    my $storage_params = {