Any noticeable difference in mixing sata speeds

[jdabb]

I need to extend my zpool, just need the drives, I noticed that my Supermicro X10SL7-F has additional four SATA II 3.0gbps ports and two SATA III 6.0gbps ports. Will I see any difference when adding 6 new drives if I am mixing the two different speeds 3.0 and 6.0gbps? I will have a total of 12 boards after adding six newer ones most of the are on SATA III 6.0gbps ports. I also need to figure how to fit 6 more in my case :).

 

[Yorick]

Nope, you'll be fine. That's 375 300 MB/s, more than any one hard drive can do read or write. Your SATA II ports won't be a bottleneck.

I am assuming you have a 6-wide raidz2 and you are planning to add a second?

 

[jdabb]

Yes, I currently have 6 in raidz2 and plan on adding a second set. My usage is getting near 95% so I might have just buy the drive off amazon and stop waiting for a deal.

 

[Yorick]

What's the size of your current drives?

 

[jdabb]

I just remember I don't even know if my Seasonic 550W Power Supply would be okay handling 12 drives?

This is the one I have.

G Series SSR-550RM 80+ Gold 550W

 

[jdabb]

4TB

 

[Yorick]

That'll be tough, you should allow 25-30W startup draw for your drives. That'd be 360W for the drives alone during startup, leaving you 190W for the rest of the system. "Probably okay", depending on motherboard and CPU.

With 4TB, you could do this: Buy 8TB or 10TB WD Elements or similar, they are inexpensive. Shuck, make sure not to supply 3.3V to them, and resilver into your existing pool one by one. You'll have double (or a little more) the capacity you have now, and you can eBay those 4TB, and you won't need to worry about physical space, heat, and power draw.

Edit: Pinout repository is at https://www.modders-inc.com/power-supply-pinout-repository/

And this is the pin to be popped out on the PSU side on a Seasonic PSU. Note other brands will have it in a different location.

 

[jdabb]

Oh wow didn't realize you can swap all them out to get more space not a bad idea. I wouldn't probably get much out of the 4TB drives, I bought them used on ebay already but I like your idea. I will check into it.

BTW, I have a Intel® Xeon® Processor E3-1231 v3 and a Supermicro X10SL7-F Mobo.

 

[Yorick]

Yeah that's a great feature, it makes expanding usable space without actually expanding the pool so easy. You get that extra space once all drives have been replaced, not before.

Caveat that 2-6TB WD Elements and WD Red are likely to be DM-SMR, that's why I suggested 8TB or 10TB. That and because getting "at least double the space" sounds like the right move.

 

[jdabb]

That'll be tough, you should allow 25-30W startup draw for your drives. That'd be 360W for the drives alone during startup, leaving you 190W for the rest of the system. "Probably okay", depending on motherboard and CPU.

With 4TB, you could do this: Buy 8TB or 10TB WD Elements or similar, they are inexpensive. Shuck, make sure not to supply 3.3V to them, and resilver into your existing pool one by one. You'll have double (or a little more) the capacity you have now, and you can eBay those 4TB, and you won't need to worry about physical space, heat, and power draw.

Edit: Pinout repository is at https://www.modders-inc.com/power-supply-pinout-repository/

And this is the pin to be popped out on the PSU side on a Seasonic PSU. Note other brands will have it in a different location.

What is the reason for not supplying the drives with 3.3v? excuse my ignorance but never thought about what voltage was being supplied to the drives.

 

[Yorick]

What is the reason for not supplying the drives with 3.3v?

Enterprise drives like the HGST HE8 have a feature where they will not spin up when they detect 3.3V, and spin up once 3.3V is gone. That's a feature for staggered spin-up in data centers, because of that initial 25-30W draw. Better to stagger the initial draw and have the PSUs spec'd for ~10W running draw, than over-provision for all drives spinning up at once.

Unsurprisingly, our little hobby boxes don't know anything about that, and although drives don't use 3.3V for anything, still supply 3.3V. Which means those enterprise drives won't spin up. Remove 3.3V, the drives are happy.

That's specific to the He8 / He10 that you get from shucked WD externals; it's not true for WD Red. WD Red will spin up just fine with 3.3V present.

 

[jdabb]

cool learned something, did not know this.