SATA question

[Andy Burns]

Ivan Gyurdiev wrote:

> I thought you got 2228MB/s ?

You're right, copy and paste error from
"4456 MB in 2.00 seconds = 2229.43 MB/sec",
4456MB/s would be truly impressive.

> Me: 400Mhz single-channel Kingston 1GB, Athlon64 3700+ 1MB L2, hdparm: 
> 1200 MB/s
> Friend: 3200 Corsair dual-channel, hdparm: 1800 MB/s
> you: p4 630 dual ddr2 667Mhz,  hdparm: <insert high # here>

yes it was 2228MB/s

and dragoran get 2765.83 MB/s on his AMD64 DDR474

> Hmm... allright. I guess dual channel helps.

I should hope so ...

> It no longer seems like an intelligent idea to remove my PATA drive from 
> the LVM group for reasons of speed, it has exactly the same performance 
> as the other one, and I get extra 80G (and not having to deal with the 
> rescue CD to shrink partitions - which btw doesn't work at the moment)

Have you tried LVM on RAID0 (if you can stand the loss of reliability)
I can't remember the hdparm numbers I got from it, I think it was not 
quite linear for the uncached part i.e. > 100MB/s, will test again soon.

I think it is also possible to do LVM stripe straight onto the disks, 
rather than LVM on top of mdraid stripe, but I can't seem to do it in 
the installer, perhaps that's considered too esoteric for anaconda, and 
I could manage it if left the space and created the LVM by hand afterwards.

Not sure if there would be a speed advantage by reducing the layering.
I will eventually split my 2x250GB drives something like 2x50GB mirrored 
and 2x200GB striped, to give me a reliable area and a large/fast area.