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Multi-actuator drives are also coming in the next few years: https://blog.seagate.com/craftsman-ship/multi-actuator-technology-a-new-performance-breakthrough/

by dktoao 8y ago

Multi-actuator drives are also coming in the next few years: https://blog.seagate.com/craftsman-ship/multi-actuator-technology-a-new-performance-breakthrough/ https://blog.seagate.com/craftsman-ship/multi-actuator-techn... That will close the performance gap a bit too I suspect. I have to wonder about power consumption though.

wtallis 8y ago
Multi-actuator hard drives will not close any performance gap. They will just help slow the decline in IOPS/TB that higher capacity drives bring. They accomplish this by essentially being multiple hard drives sharing a common spindle and helium-filled enclosure. As Seagate is currently implementing the idea, you still have only one head per platter, and at most one independently moving head per platter (but currently the stack of platters is just divided into two groups). Thus, sequential performance does not improve at all (and actually is reduced by the number of independent actuators), and random I/O increases by a small integer factor when the gap between hard drives and the slowest SSDs is already more than two orders of magnitude. However, power consumption shouldn't be much higher for this kind of multi-actuator hard drive over existing hard drive designs.
bradknowles 8y ago
Back when I was an intern at Imprimis (before they got bought by Seagate), I worked with the Manufacturing Engineers for the Wren series of 5.25” drives, including the Wren VII, which was the first consumer SCSI drive with a capacity of 1GB or more. I looked at the drive actuators at the time, and I was incredulous when the guys told me that all operations were serial. I asked why they didn’t do parallel reads and writes, and I was told that technology was already common for mainframes but too expensive for consumer gear. So, fast forward from 1989 to now, and I’m sure that idea will come back — sooner or later.

by dktoao 8y ago

wtallis 8y ago

Multi-actuator hard drives will not close any performance gap. They will just help slow the decline in IOPS/TB that higher capacity drives bring. They accomplish this by essentially being multiple hard drives sharing a common spindle and helium-filled enclosure. As Seagate is currently implementing the idea, you still have only one head per platter, and at most one independently moving head per platter (but currently the stack of platters is just divided into two groups). Thus, sequential performance does not improve at all (and actually is reduced by the number of independent actuators), and random I/O increases by a small integer factor when the gap between hard drives and the slowest SSDs is already more than two orders of magnitude. However, power consumption shouldn't be much higher for this kind of multi-actuator hard drive over existing hard drive designs.

bradknowles 8y ago

Back when I was an intern at Imprimis (before they got bought by Seagate), I worked with the Manufacturing Engineers for the Wren series of 5.25” drives, including the Wren VII, which was the first consumer SCSI drive with a capacity of 1GB or more. I looked at the drive actuators at the time, and I was incredulous when the guys told me that all operations were serial. I asked why they didn’t do parallel reads and writes, and I was told that technology was already common for mainframes but too expensive for consumer gear. So, fast forward from 1989 to now, and I’m sure that idea will come back — sooner or later.