====== Synology resize ======
====Check Sizes and volumes====
  root@test:~# df -h
  
  /dev/mapper/cachedev_0   86G   80M   86G   1% /volume1
====Stop Services====
  root@test:~# synopkg onoffall stop
  Stop SynoFinder
  Stop SupportService
  Stop StorageManager
  Stop SecureSignIn
  Stop ScsiTarget
  Stop SMBService
  Stop QuickConnect
  Stop Python2
  Stop OAuthService
  Stop HybridShare
  Stop FileStation
  Stop ActiveInsight
  stop all packages successfully
   sftp.sh  synomount.sh  tftp_serv
  root@test:/usr/syno/etc.defaults/rc.sysv# ./synomount.sh stop
  Remove udf.ko ...
  Remove isofs.ko ...
  root@test:/usr/syno/etc.defaults/rc.sysv# ./a stop
  apparmor.sh  avahi.sh
  root@test:/usr/syno/etc.defaults/rc.sysv# ./apparmor.sh stop
  Unloading AppArmor profiles
  root@test:/usr/syno/etc.defaults/rc.sysv# ./avahi.sh stop
  root@test:/usr/syno/etc.defaults/rc.sysv# ./cupsd.sh stop
  root@test:/usr/syno/etc.defaults/rc.sysv# ./irqbalance.sh stop
  root@test:/usr/syno/etc.defaults/rc.sysv# ./usbip.sh stop
  root@test:/# umount -l /dev/mapper/cachedev_0
====BTFRS resize (reducing by 10G)====  
  root@test:/# btrfs filesystem resize -- -40G /volume1
  Resize '/volume1' of '-40G'
====LV Size Check====
  root@test:/# lvdisplay
  
  --- Logical volume ---
  LV Path                /dev/vg1/volume_1
  LV Name                volume_1
  VG Name                vg1
  LV UUID                R4rD6l-bTbD-6P1B-F2jW-jOiN-XZkF-Fb48Lg
  LV Write Access        read/write
  LV Creation host, time ,
  LV Status              available
  # open                 1
  LV Size                89.00 GiB
  Current LE             22784
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     384
  Block device           249:1
====LVM Resize====
  root@test:/# lvm lvreduce -L -40G /dev/vg1/volume_1
  WARNING: Reducing active and open logical volume to 49.00 GiB
  THIS MAY DESTROY YOUR DATA (filesystem etc.)
  Do you really want to reduce volume_1? [y/n]: y
  Size of logical volume vg1/volume_1 changed from 89.00 GiB (22784 extents) to 49.00 GiB (12544 extents).
  Logical volume volume_1 successfully resized.

====Finally resize BTRFS to fill LVM====
  btrfs fi resize max /volume1