Value of reserved blocks is sometimes changed

[raleigh3]

I have set my reserved blocks to 1%.

However sometimes that value is back up to 10%.

What conditions cause that?

Do I need to put a script to set it it 1% in my startup programs?

[TheFu]

Which file system type? I've not had that issue with ext4.

$ sudo tune2fs -l /dev/sdb5 |grep -i Reserv
Reserved block count:     0
Reserved GDT blocks:      907
Reserved blocks uid:      0 (user root)
Reserved blocks gid:      0 (group root)

The default is 5% for ext4. Ok to change to zero for data file systems, but please don't do that for OS file systems.

[raleigh3]

I am using ext4.

I found this. What does the underline part mean?

With the help of reserved blocks, operating system keeps running for hours or sometimes days even though root file system is 100% full.

[The Cog]

That means there is no more space on the root filestysem (the partition that holds /). Your system is close to crashing when the disk is full. The reserved blocks are reserved for system use, not normal users, and this means the users see disk full problems before the system actually becomes un-bootable.
My guess is that the reserved blocks count goes up when it needs to use them because that's all the space that's left.
https://askubuntu.com/questions/2668...system-is-full

[raleigh3]

That means there is no more space on the root filestysem (the partition that holds /). Your system is close to crashing when the disk is full. The reserved blocks are reserved for system use, not normal users, and this means the users see disk full problems before the system actually becomes un-bootable.
My guess is that the reserved blocks count goes up when it needs to use them because that's all the space that's left.
https://askubuntu.com/questions/2668...system-is-full

Thanks.

My hard drive is 2 Tb.

I am using 2%, so running out of space should never be a problem.

[TheFu]

Thanks.

My hard drive is 2 Tb.

I am using 2%, so running out of space should never be a problem.

Any disk can run out of storage. Just make certain that /boot and /var never do. When /boot runs too low, kernel updates fail and you'll end up with all sorts of avoidable problems. When /var fills, the system will crash and may not boot. If /boot and /var are shared with /, then correcting the issues is harder, since both are problems.

2% won't prevent root-owned processes from using the storage. Watch it closely to avoid bad days.

[raleigh3]

How do I see how much /boot and /var are using?

And what does "root-owned processes from using the storage" mean?

[SeijiSensei]

cd /
du -sh *

If you mount remote filesystems from servers, you might want to add the -x parameter to limit the results to just the root filesystem.

[TheFu]

How do I see how much /boot and /var are using?

And what does "root-owned processes from using the storage" mean?

It is about file systems running out of space, not directories. If the directories are part of the / file system, then check the / file system

df -Th /

If they are separate file systems, run

df -Th /var
df -Th /boot

A handy alias that removes all the loop and fake file systems, is

alias dft='df -hT -x squashfs -x tmpfs -x devtmpfs'

[raleigh3]

Does this refer to my 2 Tbytes of space on my hard drive or the reserved blocks being used up?

It is about file systems running out of space, not directories. If the directories are part of the / file system, then check the / file system