On Sunday, April 1, 2018 at 5:45:54 PM UTC-4, Chris Laprise wrote: > On 04/01/2018 03:06 PM, 'awokd' via qubes-users wrote: > > On Sun, April 1, 2018 6:15 pm, cooloutac wrote: > >> Doesn't using trim on encrypted drive lessen security though? > > > > In my opinion, it's so marginal a security decrease it hardly bears > > mention. :) There's a link in the trim doc for further reading. > > > > I'd like to remind people: Discard and TRIM are not exactly the same thing. > > Commands like 'fstrim' only generate discards, and in a Qubes LVM setup > those discards will logically deallocate blocks in the pool, thus > freeing up space for filesystems. > > If you enable 'discard' or 'disktrim' or whatever they call it these > days in crypttab, that will result in discards being converted into > hardware TRIM commands. That is because the crypto layer is the one > closest to the hardware in our configuration. > > Does TRIM free up space? No. It helps the SSD maintain top write speeds > and perform more efficient wear-leveling. On some drives, it will also > cause the unallocated data to be wiped-out (according to vendor claims). > > Does fstrim free up space? Yes! Because it actually generates discards > and the name is misleading. > > IMO, the best thing to do is edit your dom0 /etc/fstab and add 'discard' > to the options for root fs '/'. That will free up space in a usable way > and you won't need to run fstrim. > > -- > > Chris Laprise, [email protected] > https://github.com/tasket > https://twitter.com/ttaskett > PGP: BEE2 20C5 356E 764A 73EB 4AB3 1DC4 D106 F07F 1886
according to these qubes doc it says it can hurt performance though if added to fstab? It says to use a systemd or cron job instead. Also says templates and vms already have trim enabled automatically. it also says if we are using luks to add it to crypttab or it won't work? But is this really nescessary to do in dom0? Will it make any difference if all the templates and vms already have discard by default? And so does that mean we make the cron job for dom0 we also have to add discard to crypttab? https://www.qubes-os.org/doc/disk-trim/ I apologize if I misunderstand this stuff is confusing. -- You received this message because you are subscribed to the Google Groups "qubes-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/qubes-users/368e4d8a-6d3c-492c-9e23-8d0f318922cd%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
