Understanding L1 Terminal Fault aka Foreshadow: What You Need to Know

Re:Understanding L1 Terminal Fault aka Foreshadow: What You ... by cthalupa on Wednesday August 15, 2018 @02:28AM (#17764108)

You:

> If it’s a timesliced core, then it’s not what they say they’re selling (a hyperthread).

vs.

_msw_:

> A core can be sequentially time sliced between customer instances when you use a fractional (m3.medium) or burst (T2 instances) CPU instance type.

AWS instance types page ( https://aws.amazon.com/ec2/instance-types/ ):

> Each vCPU is a hyperthread of an Intel Xeon core except for T2 and m3.medium.

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Re:Understanding L1 Terminal Fault aka Foreshadow: What You ... by h4b4n3r0 on Wednesday August 15, 2018 @04:39AM (#17764538)

Not in Google’s case. There vCPU == hyperthread. To quote https://cloud.google.com/compute/docs/machine-types: "For the n1 series of machine types, a vCPU is implemented as a single hardware hyper-thread". One more area where Google is more explicit. Only their partial vCPU instances are timesliced: "Shared-core machine types provide one vCPU that is allowed to run for a portion of the time on a single hardware hyper-thread on the host CPU running your instance".

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Re:Understanding L1 Terminal Fault aka Foreshadow: What You ... by cthalupa on Wednesday August 15, 2018 @08:45PM (#17771015)

Except this thread has been about AWS, not Google.

Who cares how Google defines things?

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Re:Understanding L1 Terminal Fault aka Foreshadow: What You ... by h4b4n3r0 on Thursday August 16, 2018 @04:09PM (#17778062)

It was about both.

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