Re: Huge Data sets, simple queries

[PFC <lists(at)peufeu(dot)com>]

> > Linux does balanced reads on software
> > mirrors.  I'm not sure why you think this can't improve bandwidth.  It
> > does improve streaming bandwidth as long as the platter STR is more than
> > the bus STR.
>
> ... Prove it.

	(I have a software RAID1 on this desktop machine)

	It's a lot faster than a single disk for random reads when more than 1  
thread hits the disk, because it distributes reads to both disks. Thus,  
applications start faster, and the machine is more reactive even when the  
disk is thrashing. Cron starting a "updatedb" is less painful. It's cool  
for desktop use (and of course it's more reliable).

	However large reads (dd-style) are just the same speed as 1 drive. I  
guess you'd need a humongous readahead in order to read from both disks.