On 19/03/2021, Carlos E. R. <robin.listas@xxxxxxxxxxxxxx> wrote: > On 19/03/2021 21.24, Johnny Dahlberg wrote: >> On 19/03/2021, Maksim Fomin <> wrote: >>>> On Friday, 19 March 2021 г., 19:09, Johnny Dahlberg <> wrote: > > ... > >> But the changes aren't mature yet. Picking 4K sector size in LUKS will >> hopefully reduce the overhead of standard queue mode. >> >> Anyway, I hope to hear from someone (perhaps even Milan :) if my >> storage layer settings in the original message are okay or if they >> could be improved. Looking forward to doing the OS installation with >> the correct settings. :-) > > Related question: > > How can one, on an exiting encrypted partition, find out what size is > using each layer, and if they are aligned or not? > > I am using encrypted partitions on SSD and I'm a bit worried. > > > -- > Cheers / Saludos, > > Carlos E. R. > (from 15.2 x86_64 at Telcontar) > > Hello Carlos! First you would check the physical sector size of your SSD. It is most likely 4096 bytes (4K). You can check this by doing: cat /sys/block/(the parent device such as nvme0n1)/queue/physical_block_size But sometimes the SSD lies and says 512 even though it actually uses 4096. So if you see 512, do an extra check online. Most likely it is truly 4096 physically. Next, check the start and end sectors of your partition and make sure they are both on MiB boundaries, or at least on 4096 byte boundaries. Next, check LUKS to make sure the "Payload offset" is 2048 or 4096 waning 1 MiB or 2 MiB respectively): sudo cryptsetup luksDump /dev/(your luks device/partition) Then check LVM to ensure your physical volume is starting at a multiple of 1 MiB and that your volume "physical extents" size is a multiple of 4 MiB: sudo pvs -o +pe_start,vg_extent_size,pv_mda_size /dev/mapper/(name of your LVM physical volume) Lastly check your filsystem. If it is ext4, the command to check its "block size" is: sudo tune2fs -l /dev/(your ext4 device) Good luck! -- Johnny _______________________________________________ dm-crypt mailing list -- dm-crypt@xxxxxxxx To unsubscribe send an email to dm-crypt-leave@xxxxxxxx
