Hello,
I need some tech clarification about the RST behavior of recent chipset, specially in raid1.
In this page Intel� Rapid Storage Technology (Intel� RST) — RAID 0, 1, 5, 10, Matrix RAID, RAID-Ready we can read: "The performance of a RAID 1 array is greater than that of a single drive because data can be read from multiple disks - the original and the mirror - simultaneously. Disk writes do not realize the same benefit because data must first be written to one drive, then mirrored to the other."
Which is true for X58 and X79 (asus motherboards) on which i installed Corsair Performance Series Pro SSDs in raid1 ( just win7 single partition), running crystal disk benchmark on X79 gave me 990MB/s sequential read speed, while on X58 (which is sata2) gave me around 500MB/s, which is infact double the max speed of a single sata channel. So, wow, it really doubles the read speed in raid1!!
Now i tested raid1 on P55, H67, H77 chipset but with standard HDD, seagate 500GB sata3 4k sectors 64MBcache, WD caviar blu 512byte sectors 16MBcache (all brand new, win7 sp1 fresh installed)
Result is quite disappointing, sequential read speed is very floating/spiking, average floating too but got no more than 75MB/s, overall is much slower than such drives tested alone (not member of any array)(around 90MB/s).
I tried diferent iRST drivers versions, with or without write cache enabled, no big diff. A real file transfer from/to single disk to raid1 array gives 50-60MB/s.
I've noticed 1% cpu load, no ram leak of iastor, just the chipset gets very very busy, both in reading or writing.
I thought the array need to be init and verified, i did, no diff.
So, the question: is there something different in X* chipsets about iRST features/performance?
Or, do i need special raid edition disks, like WD RE?
How can i enjoy the "double read speed in raid1"? Do i need X79 chipset or do i need any other raid capable chipset but special raid editin disks?
Thanks for any info, feel free to ask me further details, i can detail till the phy level if needed.