During the announcement of VFCache, Pat Gelsinger, President and COO of EMC Information Infrastructure Products, forecasted that in the future nearly all active data would be held in flash and that the days of high-speed disk drives were numbered.
Moreover, according to Alan Benway, a master performance consultant with HDS, “10K RPM SFF drives have most of the performance of 15K RPM LFF drives - less than 10% delta in our extensive lab tests when running tests on many LUNs from many RAID Groups (120 disks or more under load). They are the same for heavy write loads. The 15K drives are too costly to make for the volume and will not be manufactured much longer (18-24 months at most). Development on 15K drives has stopped, and they cannot be increased in capacity due to physics.”
Note that during Wikibon’s Peer Incite call on VFCache, EMC’s Barry Burke disagreed with Alan and claimed that many EMC customers need 15K drives for their performance advantage over 10K drives.
Nonetheless, although high-RPM drives have held the edge in Tier 1 applications, they are clearly being challenged by solid-state drives and caches – especially as the cost of flash memory keeps dropping like a rock. So why doesn’t the industry just make faster spinning drives – say 20K – since they are still much less costly than solid state drives? Ultrahigh-speed HDDs rotating at speeds exceeding 20K rpm have been researched but not commercialized due to heat generation, power consumption, noise, vibration, and other problems in characteristics, and a lack of long term reliability. Recall that the power required of a drive is proportional to nearly the cubed power of its RPM, and power translates to heat. Also note that while scientists have successfully demonstrated higher areal densities and transfer rates, they have not been able to significantly improve mechanical delays.
So, with faster hard drives out of the question and a lack of or diminishing investment in higher performance 15K drives just how long will 15K drives be available? Wikibon believes that production will begin stopping in the 2014-2015 time frame.
Action Item: Users strategic plans should include aggressive adoption of solid-state storage technologies for high performance applications and the phasing out of higher RPM hard drives. This phase-out will also alter power and cooling needs.
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