Searching for the Server in Serverless

Function as a Service (FaaS) products like AWS Lambda are more popular than ever. How do we measure and design for performance and learn more about how these services are built?

Presented at dotScale Paris 4/24/17.

Transcript

1. Searching for the Server
   in Serverless
   @smithclay
   New Relic
   dotScale April 24, 2017
   

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2. λ
   HTTP Requests
   Client App
   Simple App Architecture with FaaS
   Functions + API Gateway
   Is this going to
   (not) work for me?
   Managed Infrastructure
   λ
   λ
   λ
   

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3. Event
   Trigger
   1. Invoke
   λ
   2. Run 3. End
   Result
   Error
   Timeout
   or
   or
   

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4. FaaS: Typical Metrics
   Error Count
   Function Invocation Count
   Function Duration (ms)
   

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5. Cold Start vs Warm Start
   Event
   Trigger Handler
   Warm
   Function Invocation Time
   Create Initialize Handler
   Cold
   

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6. λ Running Commands
   const exec = require('child_process').exec;
   exports.handler = (trigger, cb) => {
   exec('whoami', (err, stdout) => {
   console.log(stdout);
   return cb(null);
   });
   }
   [LOG TIME] sbxuser_1066
   

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7. λ Discovery v2 with SSH Server
   λ
   ssh process
   
   

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8. Info from /proc
   2x Intel(R) Xeon(R) CPU E5-2666 v3 @ 2.90GHz
   cat /proc/cpuinfo
   3857664 kB
   cat /proc/meminfo
   ixgbevf (EC2 10Gbps Network Driver)
   cat /proc/modules
   c4.large EC2 Compute-Optimized Instance (?)
   

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9. c4.large instance
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   λs on a VM
   10 Gbps
   λ = 128 MB Function
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10. Cold Start Discovery in Code
    var SO_SO_COLD = true;
    exports.handler = function(trigger, cb) {
    console.log('Cold? %s', SO_SO_COLD);
    SO_SO_COLD = false;
    return callback(cb)
    }
    https://github.com/smithclay/lambda-proc-info
    

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11. Warming methodology
    Scheduled
    Event
    λ Only effective for non-
    concurrent execution!
    4 minute interval
    

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12. Cold starts, visually
    ~7 hrs ~8 hrs
    

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13. λ Host Hopping
    10.13
    10.12 10.11 10.13 10.12 10.12 10.12
    10.
    11
    # of AZs in us-west-2: 3
    

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14. Design Your Own FAAS
    High availability (multi-AZ or region)
    Elastic VMs and Automagic Freezing Containers
    Really good scheduling algorithm
    

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15. FaaS: No Silver Bullet
    "I've got a quick, computationally-intensive task that I need to
    perform occasionally in response to a well-defined event that
    isn't that sensitive to latency."
    —The Ideal FaaS Developer
    // TO DO:
    measure &&
    share
    

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16. Thanks.
    @smithclay
    New Relic
    dotScale April 24, 2017
    

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