I am a little beef-witted. Not until today did I realise that all of RAID 0, 1, 5 can improve data access speed.
When I had a computer with RAID interface about 2 years, I went online and read roughly what difference between RAID 0, 1 and 5. When I read RAID 1 is just mirroring 2 disks, I did not think carefully. I thought at that time – in RAID 1 two disks duplicate data independently, so RAID 1 only benefit data safety, not efficiency.
Today, I read further then realise RAID 1 can improve data read speed by accessing difficent piece of data on 2 disks. Of course RAID 1 does not help data write speed.
RAID 1 should be a very good choice for my server. I am also glad to learn RAID can be implemented by software.