Implementing a "sometimes" RAID on a laptop. (eSATA, SSD, RAID 1)

[Alan Cox]

> The overall RAID speed will be limited to the slowest drive. There is some

No. On a RAID 1 array read speed is armwavingly the sum of the performance
of both drive - actual numbers are a bit more complex because you now
effectively have two disk heads on non SSD media cases.

> buffering, and the system is not going to be allocating 100% of the CPU to  
> disk I/O, all the time. But, your max disk read/write throughput will, of  
> course, be limited to the slowest drive

Not always true either but a reasonable approximation for RAID 1. 1 + 0
four disk arrays can give a best of both worlds result in some cases.

Alan