On Sat, 6 Dec 2008, John Robinson wrote:
On 06/12/2008 12:11, Justin Piszcz wrote:
As far the PSU, just btw/FYI, Velociraptors consume ~4-5 watts a piece,
These are the 2.5" drives, yes?
Yup.
Even then, I think that's very unlikely; they
don't even claim any better than 6W operating, I think 8-10W is more likely.
http://www.wdc.com/en/products/Products.asp?DriveID=494
Power Dissipation
Read/Write 6.08 Watts
Idle 4.53 Watts
Independent reviews (anandtech etc) also seem to confirm this finding.
They are roughly half a regular raptor150, my system uses 200-210 watts now
that I went back with the raptor150s in my main server. Before it used
around 100-120.
Even if they are running as low as 5-6W, they're so much smaller than 3.5"
drives that heat could still cause problems. Can you check what temps the
drives have reached, using smartctl?
The temps were always between 20-30c.
Nov 25 13:00:02 p34 hddtemp[9588]: /dev/sda: WDC WD3000HLFS-01G6U0: 27°C
Nov 25 13:00:02 p34 hddtemp[9588]: /dev/sdb: WDC WD3000HLFS-01G6U0: 24°C
Nov 25 13:00:02 p34 hddtemp[9588]: /dev/sdc: WDC WD3000GLFS-01F8U0: 24°C
Nov 25 13:00:02 p34 hddtemp[9588]: /dev/sdd: WDC WD3000GLFS-01F8U0: 22°C
Nov 25 13:00:02 p34 hddtemp[9588]: /dev/sde: WDC WD3000GLFS-01F8U0: 22°C
Nov 25 13:00:02 p34 hddtemp[9588]: /dev/sdf: WDC WD3000GLFS-01F8U0: 24°C
Nov 25 13:00:02 p34 hddtemp[9588]: /dev/sdg: WDC WD3000GLFS-01F8U0: 25°C
Nov 25 13:00:02 p34 hddtemp[9588]: /dev/sdh: WDC WD3000GLFS-01F8U0: 25°C
Nov 25 13:00:02 p34 hddtemp[9588]: /dev/sdi: WDC WD3000GLFS-01F8U0: 25°C
Nov 25 13:00:02 p34 hddtemp[9588]: /dev/sdj: WDC WD3000GLFS-01F8U0: 22°C
Nov 25 13:00:02 p34 hddtemp[9588]: /dev/sdk: WDC WD3000GLFS-01F8U0: 22°C
Nov 25 13:00:02 p34 hddtemp[9588]: /dev/sdl: WDC WD3000GLFS-01F8U0: 23°C
my entire system used ~100-120watts with all 12 velociraptors on a 650 watt
PSU (now moved into a test system).
Do you have your dozen drives on a staggered start or all at power-on?
All of them start at the same time, I do not use staggered start.
I could see 12 drives starting at once causing damage to almost any 650W PSU
unless it's designed specifically for hard drive enclosures, due to the
relatively enormous current draw at startup - called inrush current.
I wonder if this is a thing of the past, I have several PSUs, all 550+
and a number of systems have 12 drives+ in them, they all surge up to 500-550
watts or so on startup but no drive and no system has any problems whatsoever,
except the velociraptors.
BTW:
Latest update is I removed the velociraptors from my main system, replaced them
with Raptor150s and yeah it does use 500+ watts at startup according to the LCD
on the UPS and also a using Kill-A-Watt but all my problems are gone, I have
been writing to the disks, running smart tests, running RAID VERIFY over the
array, writing nearly continuously and not a single error of any kind.
I think there is something wrong with Velociraptors + Linux, at some point I
suppose it would be worth trying to use them in Windows and see if I can
reproduce the problems.
Justin.
