3 ms·
As I understand it another driver in the same rack doing work is enough to effect the performance of the other drivers in the rack. This is why you use fancy ex
by doikor 5y ago
As I understand it another driver in the same rack doing work is enough to effect the performance of the other drivers in the rack. This is why you use fancy expensive "enterprise grade" drives as they can cope better with it.
https://www.dtc.umn.edu/publications/reports/2005_08.pdf https://www.dtc.umn.edu/publications/reports/2005_08.pdf
> In the presence of an external vibration caused
by adjacent disk drive seek operations the bandwidth
performance of a consumer-grade disk drive “feeling”
these vibrations will decrease about 10%-15% when
reading data and about 25%-40% when writing data
Don't really know if this is enough to actually cause damage if the disk does not have the hardware to detect this vibration.
- fuckyouriotshit 5y agoThere's also this great example of Brendan Gregg screaming at hard disks to demonstrate exactly that sort of latency spike: https://www.youtube.com/watch?v=tDacjrSCeq4 https://www.youtube.com/watch?v=tDacjrSCeq4 I don't know if the latency spike is caused by sensors detecting the extra vibrations and delaying a read or seek operation or if its just vibrations causing minor read-head errors which either require a 2nd pass (that isn't reported through to the OS via SMART) or some sort of extra processing to pull the correct signal out of the raised noisefloor. Edit: person shouting at the disks is Brendan Gregg, not Bryan Cantrill.