Re: software raid settings and ext4

[Pascal Hambourg <pascal@plouf.fr.eu.org>]

Le 24/01/2017 à 00:45, Miguel González a écrit :
>  I´m running Proxmox 4.2 which is debian jessy with a software RAID of 2
> Tb SATA disks of 7200 RPM in a dedicated server.
>
>   I have set it up using OVH Proxmox installer with ext4. I have
> realized that another server with just one SATA disk has writes of about
> 140 MB/s while this server with 2 disks has just reads around 40 MB/s:
>
>   root@myserver:~# hdparm -Tt /dev/sda
>
> /dev/sda:
>  Timing cached reads:   11800 MB in  2.00 seconds = 5903.84 MB/sec
>  Timing buffered disk reads: 136 MB in  3.17 seconds =  42.94 MB/sec

Is this a physical disk ? Then it is slow by today's standards, or 
defective, or busy doing other reads while you run the test.

There is nothing RAID or ext4 can do to make it faster.