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Comment by letmethink12 | Hacker News Reader

Nice option, how much compute power does these ARM servers offer though?

Really silly test

10$/mo droplet

  $ sysbench --test=cpu --cpu-max-prime=2000 run
  sysbench 0.4.12:  multi-threaded system evaluation benchmark

  Running the test with following options:
  Number of threads: 1

  Doing CPU performance benchmark

  Threads started!
  Done.

  Maximum prime number checked in CPU test: 2000


  Test execution summary:
      total time:                          1.5297s
      total number of events:              10000
      total time taken by event execution: 1.5219
      per-request statistics:
           min:                                  0.14ms
           avg:                                  0.15ms
           max:                                  4.68ms
           approx.  95 percentile:               0.16ms

  Threads fairness:
      events (avg/stddev):           10000.0000/0.00
      execution time (avg/stddev):   1.5219/0.00

  $ sysbench --test=cpu --cpu-max-prime=2000 run
  sysbench 0.4.12:  multi-threaded system evaluation benchmark

  Running the test with following options:
  Number of threads: 1

  Doing CPU performance benchmark

  Threads started!
  Done.

  Maximum prime number checked in CPU test: 2000


  Test execution summary:
      total time:                          27.0053s
      total number of events:              10000
      total time taken by event execution: 26.9926
      per-request statistics:
           min:                                  2.69ms
           avg:                                  2.70ms
           max:                                  2.84ms
           approx.  95 percentile:               2.72ms

  Threads fairness:
      events (avg/stddev):           10000.0000/0.00
      execution time (avg/stddev):   26.9926/0.00

Not that it'd cover for the difference but note that you're only using one of the 4 threads of the C1.

If I'm not mistaken you only have 1 CPU for a droplet at this price.

The Arm cores are also dedicated while the one on digital ocean is shared.

  ubuntu@c1-10-1-18-157:~$ sysbench --test=cpu --cpu-max-prime=2000 --num-threads=4 run                                                                           
  sysbench 0.4.12:  multi-threaded system evaluation benchmark                    
                                                                                
  Running the test with following options:                                        
  Number of threads: 4                                                            
                                                                                
  Doing CPU performance benchmark                                                 
                                                                                
  Threads started!                                                                
  Done.                                                                           
                                                                                
  Maximum prime number checked in CPU test: 2000                                  
                                                                                
                                                                                
  Test execution summary:                                                         
      total time:                          6.7674s                                
      total number of events:              10000                                  
      total time taken by event execution: 27.0485                                
      per-request statistics:                                                     
           min:                                  2.69ms                           
           avg:                                  2.70ms                           
           max:                                  7.00ms                           
           approx.  95 percentile:               2.70ms                           
                                                                                
  Threads fairness:                                                               
      events (avg/stddev):           2500.0000/17.36                              
      execution time (avg/stddev):   6.7621/0.00

For comparison, Cortex-A15-based (32-bit Tegra K1) Acer Chromebook 13:

    sysbench 0.4.12:  multi-threaded system evaluation benchmark
    
    Running the test with following options:
    Number of threads: 1
    
    Doing CPU performance benchmark
    
    Threads started!
    Done.
    
    Maximum prime number checked in CPU test: 2000
    
    
    Test execution summary:
        total time:                          8.8170s
        total number of events:              10000
        total time taken by event execution: 8.8083
        per-request statistics:
             min:                                  0.83ms
             avg:                                  0.88ms
             max:                                 21.43ms
             approx.  95 percentile:               0.95ms
    
    Threads fairness:
        events (avg/stddev):           10000.0000/0.00
        execution time (avg/stddev):   8.8083/0.00

Total time is 2.4926s with --num-threads=4.

Not a scientific measure by ANY measure, but a similar core I googled appears to kick out about 200 bogomips whereas a virtual Xeon E5-2690 v2 core on one of my machines knocks out 5984 bogomips.

I have 20 of those Xeon cores and 128Gb of RAM in a 2U.

Comparing the ratio of bogomips you'd have to get 598 of those ARM machines in a 2U to get the same bogomips.

Like I said this isn't even slightly scientific but is at least interesting trivia.

Thanks for the trivia. Just to continue on this path, how many virtualized instances can you put on your machine ?

Not tried to push it but it has 20 Windows Server 2012 R2 instances running on it at the moment all with 8Gb of memory (this is overcommitted dynamic memory). Disk is on a SAN larger than my kitchen. I span up a Linux VM quickly to do a bogomips on :)

I can probably push 40 of those onto it without it bending too terribly. If I knock the RAM down to 2Gb an instance I could probably quite happily get 64-100 on it in theory. I think memory bandwidth might kill it before CPU does.

We have two almost full (18 each) 42U racks of those machines (bar switches) so across the 720 E5 cores with 4.6TiB of RAM there is about 4.3 million bogomips.

Fun :)

(most of this is corporate fileservers, exchange, AD, various crappy apps, network appliances, web servers, SQL servers and idles at around 20% in use). If it all went off you'd need earplugs and fireman's equipment.

I found other source where they said it's around 1200 bogomips for a single core. That would means that you only need 5 times more core which is far from being an issue, 100 cores, which means only 25 processors.

Interesting!

However if you want one fast core, you're screwed :)

Yes, but considering that newer CPUs do not have increasing frequencies, I guess you are more or less doomed to scale horizontally, and not vertically anymore.

ARMv7 means they are probably using 32-bit Cortex A9 processors. Those are quite old, and probably on a 40nm process. The state of the art right now are these from Applied Micro:

http://www8.hp.com/us/en/products/proliant-servers/product-d...

AMD will enter the market soon, too, but I think Applied Micro will hold its first mover advantage with its 3rd gen chips coming next year.

http://www.eetimes.com/document.asp?doc_id=1324104

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