Amazon allows users to test their cloud for free for the first year, there are of course quite a few limitations, perhaps the most important of which is that you can only use the micro instance, which has 613 MB of RAM, I guess the hypervisor memory footprint must account for the ~150 MB that would make it up to 768 MB of memory usage.
At any rate, I wanted to find out how well these machines would perform on Linpack, so I created a very small, 4 node, cluster using my own instructions and set it to work.
All I can say is that the performance is appalling, the best test was 0.72 Gflops, see below.
It took over an hour to run a problem size of 15000, but unfortunately it crashed before it finished, even so I can't image the performance improving by much. These instances are unlikely to have even a single core all to themselves and network traffic was within Amazon's network rather than dedicated networks.
This is hardly surprising as Amazon has cluster specific instances available, still I'm pretty disappointed at the results.
I might try again with MKL to see if the performance improves somewhat.
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T/V N NB P Q Time Gflops
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WR11C2R4 1000 128 2 2 0.93 7.223e-01
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||Ax-b||_oo/(eps*(||A||_oo*||x||_oo+||b||_oo)*N)= 0.0064465 ...... PASSED
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T/V N NB P Q Time Gflops
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WR11C2R4 5000 128 2 2 254.06 3.282e-01
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||Ax-b||_oo/(eps*(||A||_oo*||x||_oo+||b||_oo)*N)= 0.0061108 ...... PASSED
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T/V N NB P Q Time Gflops
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WR11C2R4 10000 128 2 2 965.92 6.903e-01
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||Ax-b||_oo/(eps*(||A||_oo*||x||_oo+||b||_oo)*N)= 0.0060791 ...... PASSED
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Finished 3 tests with the following results:
3 tests completed and passed residual checks,
0 tests completed and failed residual checks,
0 tests skipped because of illegal input values.
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