How to cleanup Linux | Ubuntu

Well, I recently got alerts on my local system getting full. But wait a minute.
I do not have a lot on my system. I got sus about it.
Just the usual thing which will come to my mind is to check, if, my Downloads dir got too big. Sheesh, not it isn’t weighing just 16.5GB light.
Well, that’s nothing.

I then went on to look at the rest of my folder structure. Nothing was to be found. Well, then I thought let’s get on the journey to the West 😉

Sometimes we get to a point where despite very less or no usage

our Linux seems to get full. As if it got fed some nice extra large pizza with some extra cheese and chili flakes.

It is kind of funny, I had to look a lot for it.

With a lot of trial and error, I accumulated these ways.

Well, this tutorial also taught me a lot.

Youtube Tutorial

First off let’s get a bit commanding.
Ahem, just paste this into your terminal to see the disk usage

For the HDD use this
df -TH | grep “/dev/sda”

For the nvme/ssd use this
df -TH | grep “/dev/nvme*”

The output would be like this

Let’s now remove any unwanted dependencies

The auto clean will remove any broken library files.

Let’s clear some cache

So in the Linux, our cache can be in two places

/var/cache
~/.cache
To clean them simply do this.

This way you can clean your cache dir same goes for the /var/cache

System level files

As we know, systemd oversees both kernel and user-level processes, serving as the init process launched by the kernel during boot. Following this, systemctl orchestrates the startup of systemd and other crucial processes, first at the system level and then at the user level.
journald is one such process which handles the logging.

We can use journalctl to handle the logs.

Let’s just simply type sudo journalctl

Smack it, You will se something like this in the output.

BTW, to exit this log press q, or, you may prefer to watch all of it by pressing down arrow or scrolling.

Now let’s make things simpler and see the previous boot logs.
Below is the command for that.
sudo journalctl -b

It will show you the similar log again.

Now lets list all the journals

journalctl –list-boots

And you would have something like this

You might find 8 to 10 entries too.

Now you can watch for the specific date, logs by simply wirting its index as displayed.

say sudo journalctl -b -2

You will have a nice list of logs.

You can also watch since a particular duration say 4 hours.

Just type ahead sudo journalctl –since “4 hours ago”

Yet again you will have a lovely logs

Now you might want to know how much disk usage does it takes.
Here’s the command to know that.

sudo journalctl –disk-usage

Output will be like

Now to mark the active journal logs as archived we need to rotate it, kind of like, closing the notebook.
Here’s the command

sudo journalctl –rotate

Well this might be a bit confusing. Let me simplify it for you.
You can think of it as the journalctl is journaling. You went ahead
and told it to stop using this page and start writing the rest of the stuff
on the new page. That’s what it is at core.

Taking the backup

Now for some reason you decide to take the backup of the logs.
As we know, the logs are really precious.

You can do it simply like this

Or if you want to zip it

Now what if, you want to backup last 5 logs.
I got you

here is the command for it

Here is the tar way

The awk ‘{print $NF}’ part extracts the file or directory names from the output.

Deleting the journals

Now we have to delete a few journals. Consdier it like vacuum cleaning stuff.
Let’s delete everything older than yesterday(the previous day)

sudo journalctl –vacuum-time 1d

This is my output since I already cleaned yesterday.

Next you can again check your journalctl disk usage.

Cleaning the thumbnails in the cache

You might do it if you like it.
Here’s the command for that.

sudo rm -rf ~/.cache/thumbnails/*

Removing the old revisions of snaps

For my snappy friends I got you too.
You should put the below in a shell file and then run or
if you decide to directly paste it don’t copy the set -eu part

Let’s have some details about what it does.

set -eu: This line sets two options for the shell:
-e (errexit): Causes the shell to exit immediately, if any command exits with a non-zero status (i.e., an error).
-u (nounset): Treats unset variables as an error when they are referenced.
LANG=C : sets the language to English
awk ‘/disabled/{print $1, $3}’ : looks for lines containing the word “disabled” and prints the 1st and 3rd field
while read snapname revision; do: This starts a while loop, that reads each line of output from the awk command. It assigns the 1st field to the variable snapname and the 3rd field to the variable revision.
snap remove “$snapname” –revision=”$revision”: This command removes the specified snap package ($snapname) at the specified revision ($revision) using the snap remove command.