On 1/26/21 6:37 AM, Carlos E. R. wrote:
On 26/01/2021 01.27, David C. Rankin wrote:
On 1/25/21 4:07 PM, Markus Egg wrote:
If this is windows on motherboard raid, it's probably dmraid (otherwise known
as Fake RAID or BIOS RAID) -- it's not really Fake, it's just the moniker
dmraid ended up with from the hardware RAID snobs...
It is really fake, because it doesn't run in hardware: it runs in software, on
the computer CPU, with read support on BIOS so that it can boot. Once booted
it gets write code from the driver, running on the mainboard CPU, not on the
A true hardware raid doesn't use the mainboard CPU, and is transparent to the
I'm sure Neil Brown and the rest on the linux-raid list would be surprised to
learn it is fake...
It's software... (and the overhead ceased being measurable when 486 came out)
Fake is far superior to hardware. Just have a battery die on your hardware
card and drop from write-back to write-through... and then find out your
battery was discontinued 3 years ago. Now you have a hardware specific RAID
install that can no longer benefit from the hardware write-back performance at
all... Though, unless you are saturating whatever your setup is -- it really
David C. Rankin, J.D.,P.E.