Re: [gentoo-user] Are those "green" drives any good?

[Mark Knecht]

On Thu, May 10, 2012 at 11:13 AM, Norman Invasion
<invasivenorman@×××××.com> wrote:
> On 10 May 2012 14:01, Mark Knecht <markknecht@×××××.com> wrote:
>> On Thu, May 10, 2012 at 9:20 AM, Norman Invasion
>> <invasivenorman@×××××.com> wrote:
>>> On 9 May 2012 04:47, Dale <rdalek1967@×××××.com> wrote:
>>>> Hi,
>>>>
>>>> As some know, I'm planning to buy me a LARGE hard drive to put all my
>>>> videos on, eventually.  The prices are coming down now.  I keep seeing
>>>> these "green" drives that are made by just about every company nowadays.
>>>>  When comparing them to a non "green" drive, do they hold up as good?
>>>> Are they as dependable as a plain drive?  I guess they are more
>>>> efficient and I get that but do they break quicker, more often or no
>>>> difference?
>>>>
>>>> I have noticed that they tend to spin slower and are cheaper.  That much
>>>> I have figured out.  Other than that, I can't see any other difference.
>>>>  Data speeds seem to be about the same.
>>>>
>>>
>>> They have an ugly tendency to nod off at 6 second intervals.
>>> This runs up "193 Load_Cycle_Count" unacceptably: as many
>>> as a few hundred thousand in a year & a million cycles is
>>> getting close to the lifetime limit on most hard drives.  I end
>>> up running some iteration of
>>> # hdparm -B 255 /dev/sda
>>> every boot.
>>>
>>
>> Very true about the 193 count. Here's a drive in a system that was
>> built in Jan., 2010 so it's a bit over 2 years old at this point. It's
>> on 24/7 and not rebooted except for more major updates, etc. My tests
>> say the drive spins down and starts back up every 2 minutes and has
>> been doing so for about 28 months. IIRC the 193 spec on this drive was
>> something like 300000 max with the drive currently clocking in at
>> 700488. I don't see any evidence that it's going to fail but I am
>> trying to make sure it's backed up often. Being that it's gone >2x at
>> this point I will swap the drive out in the early summer no matter
>> what. This week I'll be visiting where the machine is so I'm going to
>> put a backup drive in the box to get ready.
>>
>
> Yes, I just learned about this problem in 2009 or so, &
> checked on my FreeBSD laptop, which turned out to be
> at >400000.  It only made it another month or so before
> having unrecoverable errors.
>
> Now, I can't conclusively demonstrate that the 193
> Load_Cycle_Count was somehow causitive, but I
> gots my suspicions.  Many of 'em highly suspectable.
>

It's part of the 'Wear Out Failure' part of the Bathtub Curve posted
in the last few days. That said, some Toyotas go 100K miles, and
others go 500K miles. Same car, same spec, same production line,
different owners, different roads, different climates, etc.

It's not possible to absolutely know when any drive will fail. I
suspect that the 300K spec is just that, a spec. They'd replace the
drive if it failed at 299,999 and wouldn't replace it at 300,001. That
said, they don't want to spec thing too tightly, and I doubt many
people make a purchasing decision on a spec like this, so for the vast
majority of drives most likely they'd do far more than 300K.

At 2 minutes per count on that specific WD Green Drive, if a home
machine is turned on for instance 5 hours a day (6PM to 11PM) then
300K count equates to around 6 years. To me that seems pretty generous
for a low cost home machine. However for a 24/7 production server it's
a pretty fast replacement schedule.

Here's data for my 500GB WD RAID Edition drives in my compute server
here. It's powered down almost every night but doesn't suffer from the
same firmware issues. The machine was built in April, 2010, so it's a
bit of 2 years old.  Note that it's been powered on less than 1/2 the
number of hours but only has a 193 count of 907 vs > 700000!

Cheers,
Mark


c2stable ~ # smartctl -a /dev/sda
smartctl 5.42 2011-10-20 r3458 [x86_64-linux-3.2.12-gentoo] (local build)
Copyright (C) 2002-11 by Bruce Allen, http://smartmontools.sourceforge.net

=== START OF INFORMATION SECTION ===
Model Family:     Western Digital RE3 Serial ATA
Device Model:     WDC WD5002ABYS-02B1B0
Serial Number:    WD-WCASYA846988
LU WWN Device Id: 5 0014ee 2042c3477
Firmware Version: 02.03B03
User Capacity:    500,107,862,016 bytes [500 GB]
Sector Size:      512 bytes logical/physical
Device is:        In smartctl database [for details use: -P show]
ATA Version is:   8
ATA Standard is:  Exact ATA specification draft version not indicated
Local Time is:    Thu May 10 11:45:45 2012 PDT
SMART support is: Available - device has SMART capability.
SMART support is: Enabled

=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED

General SMART Values:
Offline data collection status:  (0x84) Offline data collection activity
                                        was suspended by an
interrupting command from host.
                                        Auto Offline Data Collection: Enabled.
Self-test execution status:      (   0) The previous self-test routine completed
                                        without error or no self-test has ever
                                        been run.
Total time to complete Offline
data collection:                ( 9480) seconds.
Offline data collection
capabilities:                    (0x7b) SMART execute Offline immediate.
                                        Auto Offline data collection
on/off support.
                                        Suspend Offline collection upon new
                                        command.
                                        Offline surface scan supported.
                                        Self-test supported.
                                        Conveyance Self-test
supported.
                                        Selective Self-test supported.
SMART capabilities:            (0x0003) Saves SMART data before
entering
                                        power-saving mode.
                                        Supports SMART auto save
timer.
Error logging capability:        (0x01) Error logging supported.
                                        General Purpose Logging
supported.
Short self-test routine
recommended polling time:        (   2) minutes.
Extended self-test routine
recommended polling time:        ( 112) minutes.
Conveyance self-test routine
recommended polling time:        (   5) minutes.
SCT capabilities:              (0x303f) SCT Status supported.
                                        SCT Error Recovery Control
supported.
                                        SCT Feature Control supported.
                                        SCT Data Table supported.

SMART Attributes Data Structure revision number: 16
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE
UPDATED  WHEN_FAILED RAW_VALUE
  1 Raw_Read_Error_Rate     0x002f   200   200   051    Pre-fail
Always       -       0
  3 Spin_Up_Time            0x0027   239   235   021    Pre-fail
Always       -       1050
  4 Start_Stop_Count        0x0032   100   100   000    Old_age
Always       -       935
  5 Reallocated_Sector_Ct   0x0033   200   200   140    Pre-fail
Always       -       0
  7 Seek_Error_Rate         0x002e   200   200   000    Old_age
Always       -       0
  9 Power_On_Hours          0x0032   091   091   000    Old_age
Always       -       7281
 10 Spin_Retry_Count        0x0032   100   100   000    Old_age
Always       -       0
 11 Calibration_Retry_Count 0x0032   100   100   000    Old_age
Always       -       0
 12 Power_Cycle_Count       0x0032   100   100   000    Old_age
Always       -       933
192 Power-Off_Retract_Count 0x0032   200   200   000    Old_age
Always       -       27
193 Load_Cycle_Count        0x0032   200   200   000    Old_age
Always       -       907
194 Temperature_Celsius     0x0022   106   086   000    Old_age
Always       -       41
196 Reallocated_Event_Count 0x0032   200   200   000    Old_age
Always       -       0
197 Current_Pending_Sector  0x0032   200   200   000    Old_age
Always       -       0
198 Offline_Uncorrectable   0x0030   200   200   000    Old_age
Offline      -       0
199 UDMA_CRC_Error_Count    0x0032   200   200   000    Old_age
Always       -       0
200 Multi_Zone_Error_Rate   0x0008   200   200   000    Old_age
Offline      -       0