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Bubba|TWO raid initiate very high Load_Cycle_Count

Posted: 15 Jan 2010, 13:52
by agkbill
Hi,

After reading the post http://forum.excito.net/viewtopic.php?f=9&t=1554 I started to look at my two identical disks in my Bubba2 raid setup.

I found that the Load_Cycle_Count was far higher on /dev/sdb then /dev/sda and on top of that the count is increasing much faster.

Data I got so far show:

smartctl -d ata -a /dev/sdb | grep Load_Cycle_Count

gives:

Date Output
100112 193 Load_Cycle_Count 0x0032 200 200 000 Old_age Always - 2679
193 Load_Cycle_Count 0x0032 200 200 000 Old_age Always - 38


100113 193 Load_Cycle_Count 0x0032 200 200 000 Old_age Always - 39
193 Load_Cycle_Count 0x0032 200 200 000 Old_age Always - 2725

100115 193 Load_Cycle_Count 0x0032 200 200 000 Old_age Always - 39
193 Load_Cycle_Count 0x0032 200 200 000 Old_age Always - 2750

Will this kill my /dev/sdb disk? In the same way that are described in post "[SOLVED] [Old] WD Green Power drives may kill themselves !!"

Now it looks like I can not use the Raid function due to this.

Best regards.
/Christer

Re: Bubba|TWO raid initiate very high Load_Cycle_Count

Posted: 18 Jan 2010, 04:01
by johannes
Dear Christer,

A load cycle count increase at that rate is fully normal. If using your first sample (46 LCC/day) it will take 17 years before reaching the specified limit at 300k load cycles. Using the second pair (13 LCC/day) it will take 63 years.

Remember, the load/unload feature in the disk is to save power, and it is normal for it to operate. Problems come when they do loads/unloads every few seconds, reaching the limit (300k at some disks, 600k at others) within the normal life time of the disk.

You should not need to worry about this.

Re: Bubba|TWO raid initiate very high Load_Cycle_Count

Posted: 18 Jan 2010, 14:20
by agkbill
Dear Johannes,

Thank you for answer.

Yes, it is no practical problem, 17 years is a long, long time for a hard-drive.

But most interesting is the difference between the drives. I installed and start to use them at the same time in Bubba2 in raid mode.

Best regards,
/Christer

Re: Bubba|TWO raid initiate very high Load_Cycle_Count

Posted: 19 Jan 2010, 16:07
by vegard
Reading this thread, checking my own system, I find my /dev/sdb in a RAID has a load cycle count of 120.000 !

What, exactly, is the firmware fix that fixed the problem? Is it possible that it just works on the internal disk?

- Vegard

Re: Bubba|TWO raid initiate very high Load_Cycle_Count

Posted: 20 Jan 2010, 02:04
by johannes
Strange. And you have a newer disk, how old? Has that disk always been raid:ed, or been used for other things before? Does the LCC still increase? The updates on the newer disks should be that the timeout before entering offload mode is longer, hence it will not be "loaded" by linux again every few seconds. Should do just the same for an external disk.

Re: Bubba|TWO raid initiate very high Load_Cycle_Count

Posted: 20 Jan 2010, 15:22
by agkbill
Hi,

My disks are /dev/sda is a WDC WD10EADS-00L5B1 and /dev/sdb is a WDC WD10EADS-00P8B0

Both disk I bought new and the never been used in anything else then my Bubba2 and bubba storage in raid mode.

I used it maybe one month.

Yes LCC still increase, now it is.

2010-01-20
193 Load_Cycle_Count 0x0032 200 200 000 Old_age Always - 39
193 Load_Cycle_Count 0x0032 200 200 000 Old_age Always - 2885

That is the reason I think it might be something with how bubba2 manage raid.

Best regards,
/Christer