Striped or Linear LVM on HDD + SSD

[chmodplus777 (Mohamed Hany)]

I am still new on lvm, and I saw its robust if it used wisely. But I need really to understand the differences between lvm linear and striped methods on real hardware.

I did some searches and I found the linear method stores data in Physical Extent “PE” one by one which makes the life of the hard disk more shorter than usual “Hotspot area”. But the striped method distributes data to Physical Extent “PE” which saves the hard disk and increases the hard disk performance.

So, I want to setup this lvm schema/model on my pc:

First I have two hard disks the first one is a HDD and the second is a SSD:

sda HDD 1TB

sdb SSD 128GB

I will setup Windows for gaming stuff, alongside linux “fedor/arch/ubuntu…etc” with UEFI, So my schema will be like this

sda HDD 1TB
├─sda1      /windows-data ntfs
├─sda2      /Home         ext4       /dev/group1/home 
└─sda3      /linux-data   ext4       /dev/group1/stuff 

sdb SSD 128GB
├─sdb1      /boot/EFI     fat32
├─sdb2      /Windows      ntfs
├─sdb3      /Root         ext4        /dev/group1/root

WHERE: group1 is one volume group “VG”
Does the schema I mentioned look logical to you? Any suggestions?

First problem here, Is lvm striped method worth to setup or I just stay with the default one lvm linear method.

Second problem how the data will be stored? I made one Volume group contains part of sdd and part of sdd, this part is confusing to me. I know lvm doesn’t care about hard disk types. But still confusing.

Third as you a fedora user, did you face any problems with lvm? Is there any thing I have to keep in my mind when I use lvm with fedora?

[mattdm (Matthew Miller)]

You are only going to get a performance benefit from striping when you’re going across multiple drives. But since you have one SSD and one spinning media drive, you’re going to get mixed results from that at best.

The main advantage of LVM here would be if you’re not sure how much to use for /home and how much to use for /stuff — LVM makes it easier to adjust that.

Personally, I’d put both /home and / on the SSD (possibly not as separate partitions, or as btrfs subvolumes) and have just /linux-data on the slower drive. That way, your own configuration files and workspace stuff also loads quickly.

[chmodplus777 (Mohamed Hany)]

Thanks for your replaying…

So, to summarizing all information I have understood about LVM yet.

I can group multiple drives [SSD with SDD or HDD with HDD or even both of them SDD with HDD]. And with striping, too.

But the performance of the LVM will depend on the slowest, which in my case here HDD. So it is bad idea doing this.

The best solution in my case here is to make two volume groups, first group will group the SSD the second group will group the HDD.

Like this:

sda HDD 1TB
├─sda1      /windows-data ntfs
├─sda2      /Home         ext4       /dev/group2/home 
└─sda3      /linux-data   ext4       /dev/group2/stuff 

sdb SSD 128GB
├─sdb1      /boot/EFI     fat32
├─sdb2      /Windows      ntfs
├─sdb3      /Root         ext4        /dev/group1/root
└─sda4                                /dev/group1/snapshots

Am I right?