Hi. I must add the information that I use zswap: GRUB_CMDLINE_LINUX_DEFAULT="quiet zswap.enabled=1 zswap.zpool=z3fold zswap.compressor=lzo-rle"
Em [2021-12-16 qui 14:13:05-0300], Jorge P. de Morais Neto escreveu: > Hi! I own a Dell Inspiron 5570 laptop with 1 TB SATA HDD, a new 250 GB > NVMe SSD¹ and 16 GiB RAM. I seek reliability, durability, performance > and power efficiency. > > I do weekly duplicity backups to external 1.5 TB USB3 HDD. I'll start > also daily rsyncing some of the SSD data to the SATA HDD. > > The SSD will have 50 GB extra over provisioning and a 200 GB partition, > besides the special UEFI partition. The SATA HDD will start with 16 GiB > swap partition then a big partition. I'll put system and /home on the > SSD but all XDG user dirs² on the HDD, and tmpfs on /tmp. All three > drives will have Btrfs with space_cache=v2, noatime, zstd compression > and reasonable free breathing space. > > I use Gnome and: > - GNU Emacs > - notmuch and offlineimap (I may switch to mbsync) > - GNU IceCat, Mozilla Firefox and ungoogled-chromium > - Gajim and GNU Jami > - Gnome Boxes or Virtual Machine Manager running a VM with 2 GiB RAM and > one .qcow2 disk image currently weighting 24 GB. > - mpv > - Nextcloud (always running but rarely syncing changes) > > I use Debian stable with only official repositories, including > bullseye-backports. I manually installed GNU Guix package manager and > have 163 packages on main Guix profile. > > * Doubts > ** Backported kernel > Should I use a backported kernel as Btrfs [wiki][] recommends? I worry > that bullseye-backports comes from Debian testing with poor security. > > [wiki]: > https://btrfs.wiki.kernel.org/index.php/Getting_started#Before_you_start > > ** Strong compression during install > For lifetime and space saving, I intend to install Debian to the SSD > with compress-force=zstd:12, but then adopt compress-force=zstd. Thus > the installation will be slow---I'll do something else while the > installer works---but the installed system will be efficient, right? > > ** HDD Compression > Both HDD have a lot of already-compressed data: videos, audio, photos > and compressed archives and disk images; compress-force would force > Btrfs to recompress it all, only to discard the recompressed data and > store the original. Therefore compress=zstd:4 would be better, right? > > ** Fragmentation > Is fragmentation a concern? Is the [Gotchas][] article accurate? > > [Gotchas]: https://btrfs.wiki.kernel.org/index.php/Gotchas#Fragmentation > > ** Subvolumes > What about > https://fedoraproject.org/wiki/Changes/BtrfsByDefault#Additional_subvolumes ? > > ** Swappiness > Most performance-critical data will be on the SSD, so there will be much > less need for RAM caches; therefore I should decrease swappiness > (especially if I put swap on the SSD), right? By how much? > > * Footnotes > ¹ A 250 GB WD Blue SN550 rated for 150 TBW. > ² See the xdg-user-dir manpage. > > Kindest regards, > Jorge > > -- > - Many people hate injustice but few check the facts; this causes more > injustice. Ask me about <https://stallmansupport.org> > - I am Brazilian. I hope my English is correct and I welcome feedback. > - https://www.defectivebydesign.org > - https://www.gnu.org -- - Many people hate injustice but few check the facts; this causes more injustice. Ask me about <https://stallmansupport.org> - I am Brazilian. I hope my English is correct and I welcome feedback. - Free Software Supporter: https://www.fsf.org/free-software-supporter - If an email of mine arrives at your spam box, please notify me.