Hideous writes on LSI 150-4 RAID1?

[growse]

Just created a 300Gb RAID1 array with 2 disks on an LSI 150-4 SATA controller, with adaptive read-ahead and write-thru policies set, and I'm copying about 55 Gb of data onto it. Thing is, it's being really really slow, and the LSI performance monitor is reading about 1MB/s so windows thinks it's going to take about 5 hours to transfer 55Gb of data.

Any reason why the writes are so slow? I'm fairly sure they're not meant to be on RAID1.......

*edit: just did some iometer tests on this - using 32KB sizes, on completely non-random transfers, my windows software RAID-0 array of 2 15k SCSI disks gives about 130MB/s reads, and 68MB/s writes and the LSI RAID-1 SATA array of 2 Maxtor 300Gb Maxline 3's gives 80MB/s reads (pretty good) and 2.34MB/s writes (shocking).

HELP!

 

[growse]

The data is coming off the RAID-0 array, so no problems there. I'm not expecting stellar performance, but the anything approaching 50-60% of the read value would be nice.

I've not tried changing the drivers/BIOS - I'll check what version I've got and what the latest is and see how far behind I am...

 

[growse]

Right, I've got the latest drivers, and I'm a few letters of the firmware version, but I don't necessarily want to go through the faff of changing that if it's something else...