XPost: alt.os.linux   
   From: p_d_a_s_i_l_v_a_ns@nonetnoaddress.pt   
      
   Às 11:35 de 14/07/22, J.O. Aho escreveu:   
   >   
   > On 14/07/2022 04.16, Paulo da Silva wrote:   
   >> Hi!   
   >>   
   >> I have a USB external backup volume with btrfs.   
   >> The backup script is a simple cp -al   followed by a rsync   
   >> to update .   
   >   
   > I prefer to use snapshots and then send/receive, this tend to take a lot   
   > shorter time than cp or rsync as you will only send the changes and   
   > nothing more.   
   The script I wrote also allow for snapshots.   
   But I tend to have a lot of them for copies I need to last for a year,   
   for ex.   
   And for a big number of snapshots the fs tend to get problems, at least   
   for kernels until 5.13.   
   In my work disk I had "btrfs check" issues which disappeared after   
   deleting all snapshots.   
      
   >   
   >   
   >> The cp -al took 10-20 mins. in kernel 5.13 and before that.   
   >> Now, with 5.15, without any changes, it is taking a few hours!!   
   >   
   > I don't remember which kernel 5 version had a change in local cache,   
   > which could in some cases cause things to work differently.   
   >   
   > Have you tested with other file system on a similar usb device? This to   
   > figure out if it's related to btrfs or usb.   
   I don't have a spare USB to test. These are 4TB disks and are all being   
   used!   
   ...   
      
   > I would recommend you check up changes in the crypto layer too.   
   >   
   > Also it could be a combination of crypto + btrfs, but should in such   
   > case been resolved in later kernel versions.   
   Are there any parameters I can play with in the crypto layer?   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)