[denshi_karasu]

Hi. I'm the author of that presentation, and I just got a text message from a friend saying that I'm on the front page of Hacker News...

The one thing in that talk that I was never 100% sure of was whether it was block-mq that provided the performance improvement. It wasn't until about a year later that I came across some articles which confirmed that that it was actually due to the development of, and subsequent fixes to, the Xen persistent-grants feature.

In other words, ignore slides 15 and 16. =/

[robinanil]

Do you have updates on how the performance is on 4.x kernel versions?

[denshi_karasu]

Yes and no. I have all sorts of test results for the 4.x kernel, but they are for i3 instances rather than i2.*, so they wouldn't be directly comparable. Your question kind of makes me think I should put together an updated version of this talk; I've gathered enough material over the last couple of years that would probably be useful to somebody.

[robinanil]

Yes, that would be useful. 4.x kernels has some block io improvements and some recent phoronix benchmark shows ext4 making huge strides.

[mrmondo]

This was my first thought, kernel 3.x is more than a little dated now and there is a huge amount of IO performance and latency related changes that have been incorporated since the 3.x days.