4 ms·

The entire first page begs the question -- "what is eBPF?"

CoastalCoder 3y ago
It's actually answered (indirectly) on that page: "My report "What is eBPF?" and in-depth book "Learning eBPF" are both available for download [0] from Isovalent or with your subscription to O'Reilly's learning platform. You can buy "Learning eBPF" from any good bookstore (support your local bookshop by ordering it there!)" IIUC, you need to give contact info on that page to get the PDF. So this [1] might be a better starting point. [0] https://isovalent.com/ebpf/ https://isovalent.com/ebpf/ [1] https://ebpf.io/ https://ebpf.io/
Dylan16807 3y ago
Is a joke going over my head here, because the first sentence links to a document titled "what is eBPF?"
- yawnxyz 3y ago
  The joke is you have to give them all your information in a form to then download some B2B report... rather than add two sentences about what ePBF is
  - autoexec 3y ago
    Seriously. I really don't know why people think that's acceptable. Who sees a website titled "A beginner's guide to X" that makes people hand over their data to even get "X" defined, and thinks "This looks good to me! Sign me up!"
    - tptacek 3y ago
      This is a Github repository accompanying a book. Neither of those things were submitted here by their author. A real problem HN has sometimes is treating the entire Internet as if it was was written for HN specifically.
- tptacek 3y ago
  You can just type "What is eBPF" into Google, and the first hit will decisively answer this question for you.
  - aptwebapps 3y ago
    Although the fact that Google puts the Wikipedia BPF article in the sidebar might confuse you a little.
  - cinntaile 3y ago
    You can work around pretty much any issue like this, but you shouldn't have to. A beginner's guide should define the concept.
    - CTDOCodebases 3y ago
      I find this same issue with many things posted here. Even businesses marketing their product. My favourite is when they give you an abstraction salad instead of explaining something. I clicked the first link so I got the gist but how many other people just give up and disengage with their post? Or click the link then just close the tab without reading further.
noduerme 3y ago
After looking at the link first, this comment cracked me up. I skimmed most of the GH content without figuring out the answer; I wasn't going to click an O'Reilly link. So I gave up. Then my OCD kicked in and I got annoyed with myself for giving up, since if I'm going to waste time on HN I should really get to the bottom of things. So searched it. I found this: https://ebpf.io/what-is-ebpf/ https://ebpf.io/what-is-ebpf/ It runs sandboxed kernel extensions? Or it's a VM? Something like that? The writing of the page itself doesn't inspire a lot of confidence, but then maybe it's just over my head.
- Dylan16807 3y ago
  > It runs sandboxed kernel extensions? Or it's a VM? Yes to both of those. The kernel has a bunch of extension points that can run eBPF code in a VM. That code can make decisions for the kernel and/or track events. eBPF code can do basically any calculation you want, but it can't have infinite loops. It's loaded as bytecode, with a spec for how it's formatted and what the instructions do and what data structures are built in to the VM. The main benefit is that it runs in the kernel, so it can be triggered very very often with minimal performance impact.

It's actually answered (indirectly) on that page: "My report "What is eBPF?" and in-depth book "Learning eBPF" are both available for download [0] from Isovalent or with your subscription to O'Reilly's learning platform. You can buy "Learning eBPF" from any good bookstore (support your local bookshop by ordering it there!)" IIUC, you need to give contact info on that page to get the PDF. So this [1] might be a better starting point. [0] https://isovalent.com/ebpf/ https://isovalent.com/ebpf/ [1] https://ebpf.io/ https://ebpf.io/

Dylan16807 3y ago

Is a joke going over my head here, because the first sentence links to a document titled "what is eBPF?"

yawnxyz 3y ago
The joke is you have to give them all your information in a form to then download some B2B report... rather than add two sentences about what ePBF is
- autoexec 3y ago
  Seriously. I really don't know why people think that's acceptable. Who sees a website titled "A beginner's guide to X" that makes people hand over their data to even get "X" defined, and thinks "This looks good to me! Sign me up!"
  - tptacek 3y ago
    This is a Github repository accompanying a book. Neither of those things were submitted here by their author. A real problem HN has sometimes is treating the entire Internet as if it was was written for HN specifically.
tptacek 3y ago
You can just type "What is eBPF" into Google, and the first hit will decisively answer this question for you.
- aptwebapps 3y ago
  Although the fact that Google puts the Wikipedia BPF article in the sidebar might confuse you a little.
- cinntaile 3y ago
  You can work around pretty much any issue like this, but you shouldn't have to. A beginner's guide should define the concept.
  - CTDOCodebases 3y ago
    I find this same issue with many things posted here. Even businesses marketing their product. My favourite is when they give you an abstraction salad instead of explaining something. I clicked the first link so I got the gist but how many other people just give up and disengage with their post? Or click the link then just close the tab without reading further.

noduerme 3y ago

After looking at the link first, this comment cracked me up. I skimmed most of the GH content without figuring out the answer; I wasn't going to click an O'Reilly link. So I gave up. Then my OCD kicked in and I got annoyed with myself for giving up, since if I'm going to waste time on HN I should really get to the bottom of things. So searched it. I found this: https://ebpf.io/what-is-ebpf/ https://ebpf.io/what-is-ebpf/ It runs sandboxed kernel extensions? Or it's a VM? Something like that? The writing of the page itself doesn't inspire a lot of confidence, but then maybe it's just over my head.

Dylan16807 3y ago
> It runs sandboxed kernel extensions? Or it's a VM? Yes to both of those. The kernel has a bunch of extension points that can run eBPF code in a VM. That code can make decisions for the kernel and/or track events. eBPF code can do basically any calculation you want, but it can't have infinite loops. It's loaded as bytecode, with a spec for how it's formatted and what the instructions do and what data structures are built in to the VM. The main benefit is that it runs in the kernel, so it can be triggered very very often with minimal performance impact.