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old-gregg makes a great observation here. The addition of a ZFS benchmark without-compression is needed to isolate the compression as a factor in the speedup.

That aside, I thought this was a wonderful article with non-intuitive findings. Very interesting, CirtusDB [edit: er, CitusDB]. :-)

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old-gregg's point is valid. Since we didn't benchmark ZFS without compression we can't say for sure how much of the performance improvement is attributable to compression vs. just ZFS.

As far as AWS goes, we have noticed ephemeral disks connected to the same instance can exhibit fairly large performance differences, and attempted to control for that in our tests by reusing the same disk for each test run.

I always question benchmarks on ec2 because of "noisy neighbor" effects - maybe that's in the noise, but someone trying to replicate your results would perhaps see significantly different results depending whether their VM landed on a busy node or not... Tag this one #ymmv

+1 on testing uncompressed ZFS

I did see a blog post about MySQL with similar results (at least compression was a significant win) some time ago - disks are so slow compared to what throughput modern CPUs are capable of on these sorts of compression algorithms.

Citus

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