root 25GB?

[nodough]

Preparatory to installing Kubuntu, I've been reading the manual. It says to allow 25 GB for the root partition. My current install (Mint 17 KDE) takes up 6.5 GB for root, and I've got everything I want in it.

I've checked these forums and found one screenshot of a 20GB root partition, so I know it's not a misprint. But, really, 25GB?

I'd like to ask why so big, and if there's a way of reducing the size of the root partition. I only have 100 GB HD.

TiA.

[Snowhog]

When I create my VM's they are 75GB in size, with a 25GB root and the rest for /home (I don't create a swap partition in a VM). I find that more than adequate. Do I end up using all that space in root? No, but I want the extra room.

With a 100GB HDD, unless you are going to install more than one OS, a 25GB root is, in my opinion, not excessive. I'd create a swap partition that is equal in size to the amount of RAM you have installed (convention says up to 1.5 times the amount of installed RAM), and use the rest for /home.

[jglen490]

On a 160GB drive for my desktop unit, I have a 40GB / partition and has about 11GB of data. The rest of that disk has a 16GB SWAP partition and the remainder is /home. I think that going less than 20GB on / is pushing limits that could result in at least a temporarily filled partition, which could be fatal but fixable. I also have a 320GB that has the rest of /home (called /home/multimedia).

I understand that you have a 100GB drive and for your situation it makes sense to plan appropriately. You could get by with a 12GB / partition for a while, but you need to watch and as your Linux needs start to increase, then plan on more space. The price of hard drives is still coming down. I just bought a "new" 320GB drive for about $40.00. I suspect when I get the drive, it will probably turn out to be a cleaned up and pretty "refurb". Still ...

[jlittle]

IMO if you're considering carefully the size of the root partition, you'd be a good candidate for using btrfs. The learning curve to use it well is a bit long, but the advantages are many. In particular, there's no need for a separate root partition, the root subvolume can share free space with other subvolumes.

Regards, John Little

[nodough]

Thanks for all the replies. I'd have answered earlier, but I couldn't access the site--a 503 error.

jglen490, you say "going less than 20GB on / is pushing limits that could result in at least a temporarily filled partition." I have to ask, filled with what?

The reason I'm asking is that it's possible there's been some major change in how Linux works since my last install, several years ago. I don't use Samba, which is the biggest space hog I know of. But maybe the OS caches something it didn't used to cache, or Kubuntu is configured differently from what I'm used to. I see that my /var/cache/apt/archives/ is empty. Maybe Kubuntu doesn't automatically clear it, which would account for some of the space.

Right now, I've got every program I'd want installed and it takes up 6.5GB. 20GB is three times that size. I do need the /home space for data which I access often.

So, sorry to be a pain, but if someone could tell me what takes up all that space, I can make an informed decision on how to proceed.

PS: This being a Mint install, there's a lot of Gnome stuff installed that I probably won't have with Kubuntu.

[jglen490]

The / partition contains directories for logs, and temporary files, and update/install images aside from the OS itself and your applications. So, it can - I'm not saying will - get filled up. I keep an eye on mine,and perform simple maintenance tasks from time to time.

I don't have a lot of applications as I stick pretty close to the stock installation, plus few favorite apps. So mine stays around 11GBG to 13GB

[jlittle]

I've just stumbled on something that applies generally. Lots of software on *buntus put their files in /var by default. F.ex.:

• I used libguestfs six months ago to look into some windows backup images, and it uses a file in /var/tmp that shows as 4 GB. It's a sparse file, really only taking 520 MB, but still a lot.
• MySQL has its default data location is in /var/lib. I've got 200 MB.
• Lots of logs go in /var/log. I had to clear out several hundred MB from there after a systemd service (for non-existent hardware) failed (and logged the failure) continuously.

So if your use of the system involves running a variety of heavy software, maybe a bigger root is a good idea. But if your use has user-oriented applications like firefox, maybe not.

[nodough]

Many thanks jglen490 and jlittle, this is the kind of info I was seeking.

My entire /var takes up only 753MiB, MySQL is empty. So the 25GB depends more on how you use your system, rather than anything in the system that's generating files.

I'll probably have more questions as I plough through the manual.

Again, many thanks.

[oshunluvr]

IMO 25GB isn't necessary unless you have a TON of additional stuff you will install. I have LibreOffice, several very large games, LOTS of additional stuff, postgres, and I'm at 18GB. On the other hand, accidentally filling your root partition can be a PITA to solve.

The REAL solution IMO is to not partition at all. Use BTRFS and have all the free space you need for root and home without restriction beyond the physical size of your drive.

[nodough]

root 25GB?

My installs have a 15-16 Gb root.
Yes you can do with less but then you run into trouble when doing a large update as the downloaded software is temporarily stored in the root.

By "downloaded software" you mean the .deb packages, right? I've never done an update even near 1GB, But from what you and others have posted re: root size, it looks like I'll have to go with a minimum 15GB root. Still more than twice what I'm using now :-(

PS: I live in a very old building that's infested with bugs just the size & shape of your avatar. Nearly broke my monitor trying to kill the critter crawling in circles on it. Don't suppose you know what that bug is called?

[nodough]

The REAL solution IMO is to not partition at all. Use BTRFS and have all the free space you need for root and home without restriction beyond the physical size of your drive.

I checked out BTRFS when jlittle mentioned it. It sounds like the best solution, but I'll have to explore it further. Luckily, I found a nice tutorial on this forum.