by JoesCat » Feb 20th, '19, 10:13
Although one large big single drive is simpler to understand, having separate partitions has it's advantages.
Before mounting a partition,, you may need to check the integrity of the partition to ensure all is well.
If you come from a windows background, you may be familiar with the commandline "chkdsk /f" which you would see happen before loading windows.
Linux has similar needs and also does a file system check too.
To see this file system check process, you would run grub in a text mode instead of graphical splashscreen mode.
Different file systems have different requirements, for example ext2 has an expected full system check every 27 bootups or every Nth bootup, while ext4 does a quick check on bootup.
If you look at the details of /etc/fstab, what you may note is that first / is checked, and then after it is mounted, then the other partitions are checked, and this process can be done in parallel too, which can be even faster for separate harddrives). If you think of it this way then, it will take less time to filecheck 50GB (vs 250GB), mount "/" and then start a file system check on "/home" ("/usr", "/opt", "/var", etc...) while at the same time loading up other features from "/".
Having had failing harddrives in the past, I have run into the situation where the "/" partition was too big to be checked before loading "/", and I had to pull out the drive to do a file system check on "/" by another computer. After fixing it, it could be put back in the first computer, where it then did file checks on the other partitions and continued on from there. If you have a smaller "/", you have a greater chance of not needing to pull out the drive to do such a fix.
Last but not least, when a drive begins to fail, it tends to be a spot here, a spot there.... so you may have one partition fail completely, but you are still in time to do an emergency backup for the remaining partition(s) on the drive (this is a very strong warning the harddrive is on it's last legs of life). If your drive was only one large partition, the entire drive may be considered corrupt and unrecoverable (instead of just a small section).
In terms of partitions, if you look at Mageia's formatting tool, you'll see that you can setup different partitions with different rules and types (check expert mode).
The generated values you have, seem good, and with time, you may tune them to your needs and preferences.
For my preferences, I still like to include swap==2x size of RAM (near the top of the drive).