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Why Auto-Scaling In the Cloud Is a Bad Idea

Posted by kdawson on from the nobody-expects-the-spanish-inquisition dept.

George Reese writes "It seems a lot of people are mistaking the very valuable benefit that cloud computing enables — dynamically scaling your infrastructure — with the potentially dangerous ability to scale your infrastructure automatically in real-time based on actual demand. An O'Reilly blog entry discusses why auto-scaling is not as cool a feature as you might think."

7 of 124 comments (clear)

  1. I don't think so by Yvan256 · · Score: 5, Funny

    I think auto-scaling the clouds based on actual demand is a really great idea. I think farmers would really like that feature, in fact.

    Wait, what clouds?!

  2. Like cellphones by Tablizer · · Score: 5, Insightful

    Without a hard-limit, some people run up big cell-phone bills. If you are forced to stop and plan and budget when you exceed resources, then you have better control over them. Cloud companies will likely not make metering very easy or cheap because they *want* you to get carried away.

    --
    Table-ized A.I.
    1. Re:Like cellphones by lysergic.acid · · Score: 4, Interesting

      i think the author's point is that dynamic scaling should always be planned; partly because it results in better understanding of traffic patterns, and thus better long-term capacity planning, and partly because you need to be able to distinguish between valid traffic and DDoS attacks. still, i think the author is overstating it a bit. one of the main draws of cloud computing to smaller businesses is the ability to pool resources more efficiently through multitenancy, part of which is precisely due to auto-scaling. without the cloud being able to dynamically allocate resources to different applications as needed in real-time (i.e. without human intervention), there isn't much of an advantage to sharing a cloud infrastructure over leasing dedicated servers.

      for instance, let's say there are 10 different startups with similar hosting needs, and they can each afford to lease 10 application servers on their own. so using traditional hosting models they would each lease 10 servers and balance the load between the them. but after a few months they realize that 75% of the time they only really need 5 servers, and 20% of the time they need all 10, but an occasional 5% of the time they need more than 10 servers to adequately handle their user traffic. this means that in their current arrangement, they're wasting money on more computing resources than they actually need most of the time, and yet they still have service availability issues during peak loads 5% of the time (that's over 2.5 weeks a year).

      all 10 of these startups share a common problem--they each have variable/fluctuating traffic loads severely reducing server utilization & efficiency. luckily, cloud computing allows them to pool their resources together. since the majority of the time each startup needs only 5 servers, the minimum number of virtual servers their cloud infrastructure needs is 50. and since each startup needs double that 20% of the time, 10 extra virtual servers are needed (shared through auto-scaling). but since each startup needs more than 10 servers for about 2.5 weeks each year, we'll add another 15 extra virtual servers. so all in total, the 10 startups are now sharing the equivalent of 75 servers in their cloud.

      by hosting their applications together on a cloud network, each startup not only has their hosting needs better met, but they also stand to save a lot of money because of better server utilization. and each startup now has access to up to 30 virtual servers when their application requires it. this kind of efficiency would not be possible without a cloud infrastructure and auto-scaling.

  3. Author makes some valid points, but... by Anonymous Coward · · Score: 4, Insightful

    THe author states that one reason he doesn't like autoscaling is because it can take a while to take effect. Thats bad technology, waiting for someone to come along and improve it.

    He also says he doesnt like autoscaling even with limiters. Autoscaling with limiters makes sense to me, especially if the limits are things along the line of 'dont spend more than XXX over time Y'.

    Finally, not using autoscaling because you might get DDoS'd is just stupid. You lose business/visitors. Thats worse than paying more to avoid being taken down, because your reputation gets hurt AS WELL AS losing you business.

  4. Want to be hip /.? by Daimanta · · Score: 5, Funny

    The blogosphere has disagreed with the use of web2.0 in the cloud. Sure, we all know that data is king and that's why we use software as a service nowadays with the web as a platform using AJAX and RSS extensively. This has helped to solve the challenge of findability since lightweight companies helps to connect user needs. The fact is that the long tail is part of the paradigm of user as co-developers in server wiki-like sites. Unfortunately this brings up the problem of ownership of user generated content. But I think that perpetual betas help the architecture of participation to stimulate web2.0. Interaction does make the experience good.

    --
    Knowledge is power. Knowledge shared is power lost.
  5. Get Off My Lawn! by chill · · Score: 5, Funny

    Someone get this guy a cane to shake at the whipper-snappers. "In my day, you learned proper capacity planning or you didn't enter the data center!"

    It can take up to 10 minutes for your EC2 instances to launch. That's 10 minutes between when your cloud infrastructure management tool detects the need for extra capacity and the time when that capacity is actually available. That's 10 minutes of impaired performance for your customers (or perhaps even 10 minutes of downtime).

    Like, you could do it so much faster than 10 minutes without auto-scaling. Bah! If you've read The Art of Capacity Planning you would've mailed in the coupon for the free crystal ball and seen this coming!

    Properly used, automation is a good thing. Blindly relying on it will get you burned, but to totally dismiss it out of hand is foolish.

    --
    Learning HOW to think is more important than learning WHAT to think.
    1. Re:Get Off My Lawn! by VoidEngineer · · Score: 4, Insightful

      Properly used, automation is a good thing. Blindly relying on it will get you burned, but to totally dismiss it out of hand is foolish.

      First Rule of Automation: Automation applied to an efficient task increases it's efficiency; likewise, automation applied to an inefficient task will simply increase the problem until it's an all out clusterfuck.

      Second Rule of Automation: Automation applied to an effective task will be effective; likewise, automation applied to an ineffective task will still be a pointless waste of time.

      Or something like that. My eloquence appears to be -1 today.