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I ran the lsblk command on the terminal.

NAME        MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
loop0         7:0    0  14.8M  1 loop /snap/gnome-characters/296
loop1         7:1    0   3.7M  1 loop /snap/gnome-system-monitor/100
loop2         7:2    0  42.8M  1 loop /snap/gtk-common-themes/1313
loop3         7:3    0 181.1M  1 loop /snap/spotify/36
loop4         7:4    0  1008K  1 loop /snap/gnome-logs/61
loop5         7:5    0  54.4M  1 loop /snap/core18/1074
loop6         7:6    0 149.9M  1 loop /snap/gnome-3-28-1804/71
loop7         7:7    0  54.4M  1 loop /snap/core18/1098
loop8         7:8    0 149.9M  1 loop /snap/gnome-3-28-1804/67
loop9         7:9    0   4.2M  1 loop /snap/gnome-calculator/501
loop10        7:10   0     4M  1 loop /snap/gnome-calculator/406
loop11        7:11   0  88.7M  1 loop /snap/core/7396
loop12        7:12   0  14.8M  1 loop /snap/gnome-characters/317
loop13        7:13   0    89M  1 loop /snap/core/7713
nvme0n1     259:0    0 238.5G  0 disk 
├─nvme0n1p1 259:1    0   512M  0 part /boot/efi
└─nvme0n1p2 259:2    0   238G  0 part /

These are the snap partitions on my drive. Every loop partition has rotational set to 1. Does this affect the read/write speeds to these paritions? Or does the SSD read/write to these like it would the nvme paritions? Additionally, do these snap partitions affect the SSD's life in anyway? Is there anyway I can tell these applications to load from the nvme partition? This is my first question, I apologize if I sound stupid or have missed out on other existing answers.

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    Snaps load slower than applications installed by apt, so it's a good idea to leave the snap loops on the SSD. – karel Sep 10 at 16:18
  • The snap partitions are slow because rotational is set to 1? – Abhay Jain Sep 10 at 16:29
  • Snaps load slowly because snap packages contain the application's dependencies and the application itself bundled together into one snap package, so there are more bits to load. – karel Sep 10 at 16:39
  • Thanks for clarifying. If I compare loading snap packages from an ssd vs. snap packages from a hdd, they'll load faster on the ssd? Does having the /sys/block/loop?/queue/rotational being set to 1 impact the ssd's performance in anyway vs. it being set to 0? Additionally, these snap packages are set to read-only, so how and when are these updated? – Abhay Jain Sep 10 at 16:54
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    Snaps load faster on an SSD. Snaps are updated automatically in the background separately from apt packages whenever updates for them become available. – karel Sep 10 at 17:02
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If the files from which the loop devices are mounted, are located on the SSD, then they will be read at roughly the same speed as any other data on the SSD. As the loops are read-only, they also will not severely affect the life span of the SSD.

As snaps are SquashFS files, reading of data may be slightly slower, due to needing to decompress data as they are being read into memory.

  • This is intersesting. So setting the /sys/block/<partition_name>/queue/rotational to 1 on an SSD doesn't impact performance? Yes, them being read-only shouldn't affect the lifespan of an SSD. Even if certain snap packages get updated frequently, it shouldn't affect the SSD's health to a noticeable degree, right? Considering how small the packages are. – Abhay Jain Sep 11 at 16:13
  • Is there a way to give snap packages the freedom to be stored on disk uncompressed? – Abhay Jain Sep 11 at 16:19
  • A surprising observation is that these snap loops don't show up on gparted! – Abhay Jain Sep 11 at 16:25
  • They are loopback mounts, not partitions, so they will not show up in partitioning tools. They are not actual disks. The "rotational" property has nothing to do with performance, though having it set to true for loopback mounts which are not sourced from files on rotational disks is probably a bug. And no, you can't store them on disk uncompressed. – dobey Sep 11 at 16:53
  • Ah, thanks for clarifying! – Abhay Jain Sep 11 at 17:10

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