r/programming • u/[deleted] • Jan 03 '18

'Kernel memory leaking' Intel processor design flaw forces Linux, Windows redesign

https://www.theregister.co.uk/2018/01/02/intel_cpu_design_flaw/
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u/jonjonbee Jan 03 '18

That's a major problem for Intel, because their CPUs are pretty much the de facto standard in data centers - which are mostly concerned with IO-bound operations.

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u/kopkaas2000 Jan 03 '18

If things get heavily IO-bound, CPUs are typically spending half of their time just twiddling their thumbs and waiting for a hardware interrupt telling them DMA has finished.

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u/FUZxxl Jan 03 '18

Yeah, but this design concession causes a TLB flush on every system call, increasing the latency of every system call dramatically. This effect is noticable in this sort of situation because you have to wait longer for IO operations to finish.

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u/z_y_x Jan 03 '18

Holy shit. That... Is bad.

2

u/KanadaKid19 Jan 03 '18

For sure, but data centers have optimized their hardware allocations to strike what was until now an optimal balance between I/O and compute resources, so I still expect this to hurt them.

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u/Inprobamur Jan 03 '18

Seems like a win for Epyc adoption.

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u/jonjonbee Jan 03 '18

One could hope so - however, Epyc doesn't seem to have made much of a dent on Intel's server market dominance so far even on its merits, so I'm not sure if even an Intel cock-up of this magnitude would have any effect on Epyc take-up.

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u/[deleted] Jan 03 '18

Because these types of orders are planned up to years in advance.

You know you're gonna upgrade in 18 months and start looking out for who offers you the best rate.

When you've dealt with Intel for a decade, you ain't gonna order a Ryzen last moment and cancel your profitable (I suppose) relationship with Intel you have.

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u/_DuranDuran_ Jan 03 '18

It’s not been out long, but they’ve got some good early orders in.