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Favorite quote from the articles so far about BPF:<p>Gregg started with a demonstration tool that he had just written: it's immediate manifestation was in the creation of a high-pitched tone that varied in frequency as he walked around the lectern. It was, it turns out, a BPF-based tool that extracts the signal strength of the laptop's WiFi connection from the kernel and creates a noise in response. As he interfered with that signal with his body, the strength (and thus the pitch of the tone) varied. By tethering the laptop to his phone, he used the tool to measure how close he was to the laptop. It may not be the most practical tool, but it did demonstrate how BPF can be used to do unexpected things.
I was surprised to see discussion of NFS. NFS certainly was a big deal "back in the day" but it had its own quirks and headaches. I haven't seen NFS in 20 years, but that could simply be because of the particular worlds I live in.<p>Is it still widely used and I just happen never to see it because the environments in which I work?<p>Or is it only used for a small number of sites (or certain applications) but they happen to be extremely important ones?
> System observability with BPF<p>Initially I thought this was about recent Spectre vulnerability variants related to BPF. Then I found it is actually discussed in BPF: what's good, what's coming, and what's needed
(<a href="https://lwn.net/Articles/787856/" rel="nofollow">https://lwn.net/Articles/787856/</a>)