Re: Poor raid 1 performance?

> I've been following this here a bit, and I also don't understand why RAID1
> can't provide the same increase in speed as RAID0. With RAID0, you have
the
> data in stripes over several disks. With RAID1, you have all the data over
> several disks, which should make it possible to read a RAID1 array
> similarly to a RAID0 array (that is, the controller could just read the
> data arbitrarily from each of the two disks, and could, so to speak,
> "virtually stripe" them for reading).

Maybe, because how data is organized on each disk, it makes difficult to
stream (read sequentially) with full speed, while reading every other
sector?


.

Relevant Pages

  • Re: Analysis of disk file block with ZFS checksum error
    ... what kind of disks? ... I have an Intel ICH4 controller - nothing unusual. ... It was 64k stripes and 64k data missing, ... stripe boundaries. ...
    (freebsd-stable)
  • Re: ZFS or UFS for 4TB hardware RAID6?
    ... the raw disks in pairs, creates a mirror across each pair, ... sets, constructs stripes across each set of disks, and then ... In the RAID10 case *one* of your N/2 mirrors is degraded ... the N/2 drives in the other stripe. ...
    (freebsd-questions)
  • Re: LVM overview
    ... Manager, with lots of disks, stripes and soft partitions. ...
    (comp.unix.solaris)
  • Re: Sarge RAID install
    ... If the drive that hosts the swap partition dies, ... RAID1 protects you from that. ... performance stripes needs to be on different disks, ...
    (Debian-User)
  • Re: LVM overview
    ... Manager, with lots of disks, stripes and soft partitions. ... Now we want to replace some disks with larger ones and it's a nightmare to work out what needs to be backed up etc. ... If you're talking about Solaris Volume Manager, then that's about your only option--painstaking plotting of what is where and what will go where when you upgrade. ...
    (comp.unix.solaris)