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    343 points cvallejo | 11 comments | | HN request time: 0s | source | bottom
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    mdasen ◴[] No.22358369[source]
    Since people from Google Cloud are likely here, one thing I'd like to ask/talk about: are we getting too many options for compute? One of the great things about Google Cloud was that it was very easy to order. None of this "t2.large" where you'd have to look up how much memory and CPU that it has and potentially how many credits you're going to get per hour and such. I think Google Cloud is still easier, but it's getting harder to know what is the right direction.

    For example, the N2D instances are basically the price of the N1 instances or even cheaper with committed-use discounts. Given that they provide 39% more performance, should the N1 instances be considered obsolete once the N2D exits beta? I know that there could be workloads that would be better on Intel than AMD, but it seems like there would be little reason to get an N1 instance once the N2D exits beta.

    Likewise, the N2D has the basically same sustained-use price as the E2 instances (which only have the performance of N1 instances). What's the point of E2 instances if they're the same price? Shouldn't I be getting a discount given that Google can more efficiently use the resources?

    It's great to see the improvements at Google Cloud. I'm glad to see lower-cost, high-performance options available. However, I guess I'm left wondering who is choosing what. I look at the pricing and think, "who would choose an N1 or N2 given the N2D?" Sure, there are people with specific requirements, but it seems like the N2D should be the default in my mind.

    This might sound a bit like complaining, but I do love how I can just lookup memory and CPU pricing easily. Rather than having to remember name-mappings, I just choose from one of the families (N1, N2, E2, N2D) and can look at the memory and CPU pricing. It makes it really simple to understand what you're paying. It's just that as more families get added and Google varies how it applies sustained-use and committed-use discounts between the families, it becomes more difficult to choose between them.

    For example, if I'm going for a 1-year commitment, should I go with an E2 at $10.03/vCPU or an N2D at $12.65/vCPU. The N2D should provide more performance than the 26% price increase, yes? Why can't I get an EPYC based E-series to really drive down costs?

    Again, I want to reiterate that Google Cloud's simpler pricing is great, but complications have crept in. E2 machines don't get sustained-use discounts which means they're really only valuable if you're doing a yearly commitment or non-sustained-use. The only time N1 machines are cheaper is in sustained-use - they're the same price as Intel N2 machines if you're doing a yearly commitment or non-sustained-use. Without more guidance on performance differences between the N2D and N2, why should I ever use N2? I guess this is a bit of rambling to say, "keep an eye on pricing complexity - I don't like spending a lot of time thinking about optimizing costs".

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    boulos ◴[] No.22360348[source]
    Disclosure: I work on Google Cloud (and really care about this).

    The challenge here is balancing diverse customer workloads against the processor vendors. Historically, at Google, we just bought a single server variant (basically) because almost all code is expected to care primarily about scale-out environments. That made the GCE decision simple: offer the same hardware we build for Google, at great prices.

    The problem is that many customers have workloads and applications that they can’t just change. No amount of rational discounting or incentives makes a 2 GHz processor compete with a 4 GHz processor (so now, for GCE, we buy some speedy cores and call that Compute Optimized). Even more strongly, no amount of “you’re doing it wrong” actually is the right answer for “I have a database on-prem that needs several sockets and several TB of memory” (so, Memory Optimized).

    There’s an important reason though that we refer to N1, N2, N2D, and E2 as “General purpose”: we think they’re a good balanced configuration, and they’ll continue to be the right default choice (and we default to these in the console). E2 is more like what we do internally at Google, by abstracting away processor choice, and so on. As a nit to your statement above, E2 does flip between Intel and AMD.

    You should choose the right thing for your workloads, primarily subject to the Regions you need them in. We’ll keep trying to push for simplicity in our API and offering, but customers really do have a wide range of needs, which imposes at least some minimum amount of complexity. For too long (probably) we attempted to refuse, because of complexity, both for us and customers. Feel free to ignore it though!

    replies(5): >>22360916 #>>22361132 #>>22361552 #>>22363902 #>>22365298 #
    alfalfasprout ◴[] No.22361132[source]
    I mean, this mentality often is wrong. Scaling out actually isn't the right solution for everyone. It works for Google given that primarily web services are offered. It does not work for workloads that heavily rely on the CPU (think financial workloads, ML, HPC/scientific workloads) or have realtime requirements. In fact, for many ETL workloads vertical scaling proves far more efficient.

    It's long been the "google way" to try and abstract out compute but it's led to an industry full of people trying to follow in their way and overcomplicating what can be solved on one or two machines.

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    1. erulabs ◴[] No.22361446{3}[source]
    Except, almost without exception, eventually the one or two machines will fall over. Ideally you can engineer your way around this ahead of time - but not always. Fundamentally relying on a few specific things (or people) will always be an existential risk to a big firm. Absolutely agree re: start small - but the problem with “scale out” is a lack of good tooling - not a fundamental philosophical one.
    replies(5): >>22361542 #>>22362219 #>>22362898 #>>22363481 #>>22363618 #
    2. aidenn0 ◴[] No.22361542[source]
    Plenty of services can deal with X hours of downtime when a single machine fails for values of X that are longer than it takes to restore to a new machine from backups.
    replies(2): >>22362715 #>>22364102 #
    3. alfalfasprout ◴[] No.22362219[source]
    It is a philosophical one when you design around scaling out at a high rate. You incur significant additional complexity in many cases along with increased overhead.

    It's fallacious to think that relying on "n" things is strictly safer than "3" things where n is large. That's not quite true due to the significant complexity increases when dealing with large "n" and accompanying overhead.

    For web applications (which I suspect the majority of HN readers work on) then sure, but plenty of realtime or safety critical applications are perfectly ok with three-way redundancy.

    replies(1): >>22364859 #
    4. chucky_z ◴[] No.22362715[source]
    I'd like to add to this and say that a server being down for 6 hours, that if over the life of its uptime (months? years?) saves uncountable number of hours on computations and complexity, is so worth it.

    Heck, even a machine like that being down for a week is usually still worth it.

    5. PudgePacket ◴[] No.22362898[source]
    I've heard lots of anecdotes from big sites doing fine with a small number of machines.

    eg stackoverflow only has 1 active DB server, and 1 backup.

    https://stackexchange.com/performance

    replies(1): >>22363499 #
    6. lmeyerov ◴[] No.22363481[source]
    Totally. We could replace our GPU stack with who knows how many CPUs to hit the same 20ms SLAs, and we'll just pretend data transfer overhead doesn't exist ;-)

    More seriously, we're adding multi-node stuff for isolation and multi-GPU for performance. Both are quite different... and useful!

    7. endymi0n ◴[] No.22363499[source]
    Actually, this makes a lot of sense. Reasoning about a single machine is just way simpler and keeps the full power of a modern transactional database at your fingertips. Backups keep taking longer and disaster recovery isn‘t as speedy anymore, but we‘re running on Postgres internally as well and I‘d scale that server as big as possible (even slightly beyond linear cost growth, which is pretty huge these days) before even thinking about alternatives.
    8. mrich ◴[] No.22363618[source]
    The solution often is to have a warm standby that can take over immediately. You do not get any distributed overhead that is present in a fully load-balanced system during normal operation, and only pay a small amount in the very exceptional failure case.
    9. darkwater ◴[] No.22364102[source]
    I do not agree, and it is not my experience.Mind you that I've always worked in small/mid-sized businesses (50-300 employees) and basically every service has someone needing it for their daily work. Sure, they may live without it for some times, but you will make their lives more miserable.

    And anyway if you already have all in place to completely rebuild every SPOF machine from scratch in a few hours, go the extra mile and make it an active/passive cluster, even manually switched, and make the downtime a minutes thing.

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    10. Bad_CRC ◴[] No.22364859[source]
    I work a lot with voip systems and it's much much easier to have one big machine that trying to make it work distributed...
    11. aidenn0 ◴[] No.22376467{3}[source]
    A small amount of work over a long period of time (i.e. setting up a redundant system) may be worse than losing a large amount of work in a short period of time.

    Single machines just don't fail that often. I managed a database server for an internal tool and the machine failed once in about 10 years. It was commodity hardware, so I just restored the backups to a spare workstation and it was back up in less than 2 hours. 15 people used this service and they could get some work done, without it, so there was less than 30 person-hours of productivity lost. If I spent 30 hours getting failover &c. working for this system over a 10 year period, it would have been more hours lost for the company than the failure caused.