Hi ... just precleared a couple of 4TB drives (99 hrs for 3 cycles!!).

 

Checked all the reports and everything is fine, no errors before or after.

 

But ..... i have this line in my report

 

'SATA Version is:  SATA 3.1, 6.0 Gb/s (current: 3.0 Gb/s)'

 

It shows 'current' as 3.0Gb/s ... my hardware is an HP54L microserver and i've modded it to enable all ports to run at full speed (or so I thought).

 

Is this a problem or should i be digging deeper?

One of your SATA cables may have failed to qualify for 6.0Gb operation.  It's irrelevant, however, since no spinning platter drive exceeds the SATA-II speeds (3.0Gb) operation anyway.    You can try replacing the cables, but I'd not worry about this at all.  If the reports are clear, the drives are fine.

 

Thanks garycase ... think i need to get my head around this but you're saying that no SATA3 drives, advertised as 6Gb/s capable actually transfer at higher than 3Gb/s, yes? Yet 'addon' sata cards also state 6Gb/s capabality so i'm trying to square that circle. These drives are Seagate NAS sata3, are you saying they will never reach 6Gb/s even with an addon controller? Apologies for the dumbness but i'm confused now ... thx!

 

One more question to do with starting sector.

 

In my UnRaid settings I have default as 'MBR 4k aligned'.

 

I did not use any switch (-a or-A) in my preclear command as I was told that the script handled any advanced format drive without the need for swithces and would align accordingly. My report shows a start sector of '1' when I would have expected a start sector of 64, correct or not?

The only time the actual transfers between the PC's memory and the hard drive will be at interface speed (i.e. 6Gb/s for SATA-III) is when data is being transferred to/from the disk's buffer.    That is a VERY tiny percentage of the time (well below 1%) ... it's essentially irrelevant in terms of overall system performance.  The sustained data rate -- i.e. the speed at which data can be transferred off of the platters -- is well under 200MB/s => and it's nowhere near that high unless you're using disks with high areal density (e.g. 1TB/platter or a 7200rpm unit with 800MB platters).

 

The ONLY time a SATA-III controller really makes a difference is if you're using it with a SATA-III SSD.

 

The only time the actual transfers between the PC's memory and the hard drive will be at interface speed (i.e. 6Gb/s for SATA-III) is when data is being transferred to/from the disk's buffer.    That is a VERY tiny percentage of the time (well below 1%) ... it's essentially irrelevant in terms of overall system performance.  The sustained data rate -- i.e. the speed at which data can be transferred off of the platters -- is well under 200MB/s => and it's nowhere near that high unless you're using disks with high areal density (e.g. 1TB/platter or a 7200rpm unit with 800MB platters).

 

The ONLY time a SATA-III controller really makes a difference is if you're using it with a SATA-III SSD.

 

So, let's say that i need an extra couple of sata ports (this microserver has 6 available on mobo inc esata) at some point, i'm wasting my money by going for a sata3 addon card and would be as good going for a sata2, yes?

 

I've just checked the N54L specs and it only has an onboard 3Gb/s controller which i hadn't realised. Doesn't matter then as i'm assuming there's no sata 2 4TB drives around anyway and it's capacity, not performance, i'm after.

 

Any ideas on my preclear starting sector of 1?

I've just checked the N54L specs and it only has an onboard 3Gb/s controller which i hadn't realised.

 

:)

... as I noted above, that's completely irrelevant.  Your performance would be NO different if the ports were SATA-III (6Gb/s).

 

 

 

Any ideas on my preclear starting sector of 1?

 

Not a problem.  If you look at the drives in UnRAID, you'll see they're GPT, 4k-aligned.  That's all that matters.

 

 

Thanks ... glad i havent got to go through another 99 hours  .

 

Understood on the sata front, cheers!