Is this Bad I/O for this setup?

Comments

• Damian Member

  March 2012

  FWIW, regarding "Green" drives:

  In terms of cost, using a green hard drive compared to a normal one makes very little difference. Assuming your drive spends 4 hours reading and writing and 20 hours idle per day, switching from the WD Black to Green saves you only 45 kilowatt-hours per year. The national average cost of a kilowatt-hour is 11.93 cents, netting you a whopping $5.38 per year for your sacrifice of 1800 RPM. For comparison, changing one 60-watt lightbulb used 4 hours a day to a 7-watt fluorescent one saves you more, about $9.23 per year.
• MrDOS Member

  March 2012 edited March 2012

  I also know that once upon a time, WD Greens were highly disadvised for use in any form of RAID (I think due to some sort of aggressive write queuing, but I could be way off); I'm not sure if that's still the case or not.
• Jacob Member

  March 2012

  @MrDOS
  You are right, Gren drives are not built to be put into RAID Arrays and doing so will cause bad I/O and the WD Ears series have problems syncing if using different models/makes of drives.
• torqhost Member

  March 2012

  Well, for software RAID they are fine. They should not be used in hardware RAID configurations. But in any case the performance will be inconsistent even if you disable the power saving features.
• Maounique Host Rep, Veteran

  March 2012 edited March 2012

  @dmmcintyre3 said: Single WD green drive (250gb)

  dd if=/dev/zero of=test bs=16k count=64k conv=fdatasync;rm test

  65536+0 records in
  65536+0 records out
  1073741824 bytes (1.1 GB) copied, 12.5311 s, 85.7 MB/s

  root@debmain:~# dd if=/dev/zero of=test bs=16k count=64k conv=fdatasync;rm test
  65536+0 records in
  65536+0 records out
  1073741824 bytes (1.1 GB) copied, 16.0442 s, 66.9 MB/s
  That is my machine with 2 TB green WD doing almost nothing regarding I/O. They arent too fast, still faster than Samsung, tho. SATA 2. My home server uses samsung EcoGreen because they are even quieter and cooler.
  M