03-23-2010 11:40 AM - edited 03-23-2010 11:44 AM
I bought a WD Green Caviar for my new computer. I choose the green line because of its low noise level. But I am no longer sure that it was a good choice. Yes, the drive is really silent and it is fast enough for me. But I had two strange system crashes during the last 3 weeks ( with my old computer I had no system crash in 7 years!) where the kernel reported I/O errors during disk operations - after a reboot everything was fine again. I did a file system check and SMART self test with no errors found. There are similar reports in this forum which make me belief that the Green Caviar is responsible for these crashes.
But today I discovered something else that worries me. I had a look at the SMART data and I discovered a very high Load Cycle Count for this 1,5 month of operation. Here is the output of smartctl:
ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 4 Start_Stop_Count 0x0032 100 100 000 Old_age Always - 132 9 Power_On_Hours 0x0032 100 100 000 Old_age Always - 514 12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 131 193 Load_Cycle_Count 0x0032 189 189 000 Old_age Always - 35870
As you can see the drive has already gone through 6% of the permitted load cycles. The drive in my old computer had only ~1360 load cycles in three years .
Somebody told me these numbers are meaningless, but I am not so sure. What do you think?
Solved! Go to Solution.
03-24-2010 04:36 AM
I found out that it is a known problem - there are numerous reports around. The Green Caviar puts its heads into parking position after 8 seconds idle time. Now when the OS periodically performs a disk operation the heads will be permantly parked and un-parked on an low loaded system which causes the load cycle count to explode, So it is more a desktop than a server problem. There are romours that the Green Caviar is advertised as desktop product ...
I wounder what will happen when I return the drive to WD for replacement in a few month when it will surely have failed!
Green Caviar sucks!
03-25-2010 12:41 AM
03-25-2010 12:54 PM
hdparm -B doesn't work - you get an error message.
hdparm -i tells you that the drive doesn't support APM (AdvancedPM=no).
There are reports that WD is aware of the problem but doesn't officially admit the problem. When you contact WD support they will send you a DOS tool called wdidle3 which allows you to change the timer settings. I guess they use vendor specific commands. I contacted them yesterday - no response yet. I found a copy on the Internet but I won't use software from insecure sources.
Today I did a test: I set up a cron job that logged the load cycle count every 30 minutes. On my idle computer (I was at work) I got frightning results. Now here is an excerpt:
2010-03-25 10:00:01 37605 2010-03-25 10:30:02 37665 2010-03-25 11:00:01 37725 2010-03-25 11:30:01 37785 2010-03-25 12:00:01 37845 2010-03-25 12:30:01 37905
As you can see an increase of 60 every 30 minutes. That's because the kernel flushes dirty buffer pages every 30 seconds. If it goes on like this the drive will reach its life time limit within a few month.
03-25-2010 01:35 PM
03-25-2010 02:44 PM
03-26-2010 01:07 AM
Today I bought one and I have one week to return it..
I would return it and get a non-green one. This IntelliPark feature is total rubbish. It may save a few mW but its risks data loss and it noticeable slows down the drive. The Green Caviar drives are really bad designed products. Why haven't they implemented some smart algorithm that monitors how the OS accesses the drive and adjusts the idle time to a sane value? I am sure parking and unparking the heads every few seconds effectively increases the power consumption and destroys the the drive.
03-26-2010 06:32 AM - edited 03-26-2010 06:33 AM
did you read this (are you a Linux-user): http://wdc.custhelp.com/cgi-bin/wdc.cfg/php/enduse
I do'nt know how often the head is parking because I can't access the SMART-status (The drive is temporary external by a SATA to USB hub) Fysically the drive feels superb, sometimes I hear the heads, but it is no more than twice a minute. I have some days to decide on holding the drive.
03-26-2010 06:38 AM
What if you make a background job to intentionally touch the disk every 6 seconds to prevent it from parking? Or you can enable laptop mode to get the kernel to stop constantly flushing buffers it does not have to. This is how you get a disk to stay spun down when you put it to sleep. I'd say enable laptop mode and when you're going away, manually tell the drive to sleep with hdparm -y. That way it spins down and stays spun down, with no load/unload cycles while you aren't around.