RAID 1 Read Performance

[Euroclydon37]

The vast majority of articles that I read say that there is no performance gain with RAID 1. This makes perfect sense to me, as it is just a copying of the data.

However, I recently read an article that said that RAID 1 arrays are often set up wrong and that the system could be set to read from both drives simultaneously, increasing read performance to near RAID 0 levels. (Write speeds and storage capacity are still half of RAID 0)

Is there any truth to this? I haven't been able to find anything on the subject specifically since that article.

 

[jsmithepa]

Raid1 SPANNING - Writes to volume disk1, then when runs of of space continues with disk2, transparent to user. No speed advantage.

Raid1 STRIPPING - Writes to both disks simultaneously, thus theoretical bumps speed to 200%. Problem is, when one disk fails, all data both disks unretrievable.

 

[pauls3743]

Using CrystalDiskMark on a pair of RAID 1 (mirrored) SATA 3 SSDs (600MB/s) on an intel rapid storage technology controller I've had read speeds around the 800MB/s mark. So yeah, I think there's some merit to it.

Write speed wasn't so hot though, it was more single disk speeds, but that's ok.