this post was submitted on 08 Jun 2025
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Hello, cant attach image cause of file size, i have fresh void linux base install in tty and btop tells me i use 500-600MiB of ram but my top 3 services uses 7-25M and rest are 5>, free -m also tells me 600M but why this much with not much services?

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[–] [email protected] 14 points 4 hours ago (1 children)
[–] [email protected] 1 points 3 hours ago (1 children)

So should i do used - cache = actual ram? Why then ive seen people have like 100M of ram, could u check my repplyes on this post?

[–] [email protected] 0 points 3 hours ago

@[email protected] basically hit the nail on the head looking at available and subtracting from total ram will give you the closest answer to how much ram is being used.

[–] [email protected] 3 points 4 hours ago (1 children)

Can you share the output of free? There are multiple values to read from that.

[–] [email protected] 1 points 3 hours ago (1 children)
[–] [email protected] 8 points 3 hours ago* (last edited 3 hours ago)

252 of that 592 used memory is buffers/cache, not application memory. That is used by the kernel for kernel buffers and the filesystem cache - IE files read by something at some point. The kernel keeps them in memory in case they are needed again to speed up file reads. You can effectively ignore these vales as they will always grow to fill your ram and will be evicted when programs require memory and there is not enough free.

These tools are not lieing to you, just telling you something other then what you are reading into them. Tracking and reporting on what is using memory is a complex topic and here used is just what is physically allocate. It doesn't mean much over all as it always tends to be full of your system has been running for a decent amount of time. Available is typically the more useful one to look at as it is an estimate about how much the kernel can reclaim now if an application request it without needing to swap things out.

[–] [email protected] 5 points 5 hours ago* (last edited 5 hours ago) (1 children)

Are you certain its actual ram usage and not reserved ? Usually when a program requests huge amounts of ram it is not given it until it actually writes to it. Try running free and check what it says.

[–] [email protected] 1 points 5 hours ago (1 children)

Freshly rebooted into tty and used free and used: 618876, the thing that takes the most ram is NetworkManager with 17M of ram

[–] [email protected] 2 points 4 hours ago* (last edited 4 hours ago) (1 children)

Ah, I accidentally read over that you used free -m.

By top 3 services do you also include any programs ? For me htop itself already consumes 10 MB, what other processes are running ?