Re: Re: IHC7 RAID-1 or Kernel Software RAID-1?

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]




Oh, if you want to try the hardware raid is faster than software raid
line, then I have got news for you. Some time back, there was this i960
chip from Intel that was very popular on hardware raid solutions. It
sucked. It sucked big time. Yes, it did offload a fair bit of cpu
processing from the AMD/Intel cpus then but the i960 was so slow, using
software raid was just a no brainer since you get twice the speed for a
10% cpu load.

Today, hardware raid come with big memory caches and that is the only
reason they are faster than software raid in certain cases like raid5.
Any hardware raid card that does not come with a memory cache is not
likely to be much faster than a software raid solution especially when
using the more complicated raid arrays like raid5/6. You will notice
that products from 3ware and Areca all now come with memory caches.
There is no such thing as a cheap hardware raid card.
The i960 doesn't count, since it hasn't been used for a while. I think it was
designed as a printer rendering engine processor, and was never designed for
the load that raid imposed.


I did say that the i960 WAS very popular some time back.

But yes, I suppose I was not very explicit on the fact that although hardware raid cards today come with much more powerful processors, they still need memory cache to get performance benefits over software raid.
_______________________________________________
CentOS mailing list
CentOS@xxxxxxxxxx
http://lists.centos.org/mailman/listinfo/centos

[Index of Archives]     [CentOS]     [CentOS Announce]     [CentOS Development]     [CentOS ARM Devel]     [CentOS Docs]     [CentOS Virtualization]     [Carrier Grade Linux]     [Linux Media]     [Asterisk]     [DCCP]     [Netdev]     [Xorg]     [Linux USB]
  Powered by Linux