[bullen]

Aha, thanks for that very valuable information!

T3 look cheaper and better than E2 then, my only problem is region placement where Iowa and Taiwan are more central than anything AWS offers (still no central US region!?).

I'm in the MMO business, so very specific requirements.

[boulos]

Disclosure: I work on Google Cloud.

T3 is pretty different (even in unlimited mode) than E2. As an example, t3.xlarge (4 vCPU, 16 GB, $.167/hr, so $.042/hr/vCPU roughly) only has a baseline performance of 40% (so 1.6 vCPU). If you cross that threshold in unlimited mode you pay an additional $.05/vCPU/hr (so more than doubling your cost). By comparison an e2-standard-4 is $.134/hour even if you run it flat out.

We take on the statistical multiplexing over the datacenter and move VMs around, instead of pushing it to you as an economic or performance-throttling risk when you need it most. If you want a burstable type, we do have an e2-{micro, small, medium} that only guarantees you 12.5%, 25% and 50% of your 2 guest-visible vCPUs. But that's more fit for dev workstations and so on.

[bullen]

Are the shared E2 cores (e1-micro f.ex.) guaranteed to be on different physical cores? See my reply to AWS below.

[ti_ranger]

> We take on the statistical multiplexing over the datacenter and move VMs around

You're implying here that EC2 doesn't do this.

On what basis?

[boulos]

Sorry if I was unclear. In unlimited mode, if you sustain greater than your baseline percentage, you pay for it (the key point of the sentence you’re quoting is that we take on the risk). One reason for this happens to be because AWS doesn’t do migration (yet?), but instead does an awesome job of doing in-place upgrades (see their talks on Nitro, for example).

[_msw_]

Disclosure: I work for AWS.

We have many tools in our toolbox at our disposal: non-disruptive in-service updates moves live migration from a "must have to operate compute cloud service at all" to "helpful in some scenarios when the workload and/or situation warrants the impact to performance during precopy / potential post-copy phases."

But I would not assume that EC2 does not have that particular tool in the "fully production, and used" toolbox.

[dodobirdlord]

I have my doubts, in the past I've received decom-notifications that EC2 was going to be shutting down my instances in the near future due to underlying hardware failure (very helpful, since I was in the middle of triaging why the instance was behaving strangely). Seems like a poor customer experience to reap running instances if live migration is on the table.

[bullen]

Are the T3 cores guaranteed to be on different physical cores?

When are you building a central US region?

[_msw_]

Disclosure: I work for AWS

T3 instances provide hyperthreadded vCPUs to EC2 instances, and the Nitro Hypervisor uses a core based scheduler (coscheduler) to ensure that cores are never shared between two EC2 instances.

Upstream Linux kernel changes that are based on some of the changes in the Nitro Hypervisor were posted to lkml in 2018: https://lwn.net/Articles/764482/

I hope to see the GCE team contributing more to the ongoing discussion on core based scheduling!

[bullen]

Are the E2 cores guaranteed to be on different physical cores?

[Dylan16807]

Every search result I can see says that EC2 doesn't do live migration. You can try to balance things but you can only do so much if you can only move a VM when it happens to reboot by itself. (And there's no evidence I can find that they even do that.)

[_msw_]

Disclosure: I work for AWS on EC2

EC2 instances that have no local storage state can move between hosts in response to events like reboots.