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USB - NVMe SSD enclosure (for RPi class)

Gordon Haverland
 

I've had a couple of external USB (one is also eSATA) enclosures for
spinning rust disks in them. Since I am have one and a second is
coming of RPi type computers which will have a NVMe SSD in it, I
thought it best to pick up an enclosure so that I can put the "system"
onto the SSD in a more comfortable setting. I ordered a QNine.

I have set up a few motherboards with NVMe SSD on the motherboard, and
was sort of expecting something similar. It turns out the "post" to
support/fix the SSD in place, has a notch in it. So, it is the notch
which engages the SSD, and the screw comes in from the back. First
time I seen this.


There doesn't seem to be any reason to avoid GPT for the partition
type. While there are older articles about btrfs having problems, I am
not seeing issues there either (with not enough research being done).

So, I am inclined to set up a "root" filesystem (so to speak). I think
that what I eventually end up with, is the thing that does the low
level booting is either a eMMC or a microSD card, and towards the end
of booting, this "root filesystem" is pointed to and you are running
form a NVMe.

I think the 2 machines I will have in the near term (Rock Pi 4b and a
PinebookPro laptop) both have 4GB of RAM. Lots of people don't use
swap, I always have. So, I am inclined to set aside 8GB for a swap
partition. The root partition has to hold /etc, /bin, /sbin and /lib.
And maybe the /root part of the filesystem needs to be bigger than
desktop machines? The server for my LAN, is using 691M for the root
partition. Double that? The /usr partition on my server is about 5GB
used. The /usr/local is just over 500MB. The /var and /var/log
partitions are smallish, /var/log has 70 MB in it. I like /tmp to be
about the same as swap. Which mostly leaves /home.

This SSD is 954GB.

swap 8GB
/ 2GB ext4
/tmp 8GB ext2
/usr 8GB ext4
/var 4GB ext4
/usr/local 2GB ext4
/var/log 2GB ext4

So, that is 34 GB allocated. Only 920GB left. Leave about 1MB between
partitions, and maybe only set up a 460 GB /home using btrfs for the
file system?

That leaves lots of space for "levelling" type activities that flash
often likes to do.

Any problems with that from people who have been using RPi? Both
computers I will have of this "initial variety" are using the Rockchip
RK3399, which has 6 cores in a big.LITTLE configuration.

Thanks.

--

Gord