[Kernel-meetup] Pune kernel meetup for February - meeting minutes

[Pankaj Gupta]

Hello,

Thanks everyone for attending this meet-up in Red Hat premises Pune.

Below is summary of meetup:

* Approximately >20 guys attended the meet-up. Overall there was diverse
  crowd comprised of people from different companies/institutes. Some were
  experienced in kernel and related areas, want to learn more and contribute.
  Also, there were few students who were genuinely interested in the topic.
  
  I later realized python meetup happening in parallel, thanks to that as well.


* First session was: "Submitting first patch upstream" by Jeetendra. It was
  a nice interactive session with an example of how to send your first patch.

  Started with version control system and benefits concentrating on git.
  Jeetendra demonstrated use of "checkpatch.pl", "get_maintainer.pl" with some 'git' concepts
  like create new branch for every new work and commit individual changes to new patch in
  that branch.

  He created a patch and compiled kernel after fixing a 'trivial style issue'.
  He used 'git format-patch' to create patch from local commit and sent patch
  using 'git-sent-mail' to staging mailing list.
  Some discussion about git trees like staging, stable, linus and distro etc.
  He also pointed to kernel documentation for all the steps. Attendees asked some doubts.

  Siddhesh added with some benefits of git version control and more tips.

* Next we had 10 minutes meetup/Networking till next session starts. Also, small
  refreshment (Thanks to Red Hat )

* After that I presented session on "Overview of Linux Memory Management"
  I tried to explain, why we we need 'virtual memory' and how linux supports
  it with the help of 'paging'. Idea was to start with basics. Also explained some
  of the internals with MMU, TLB & page tables. Memory allocation using kmalloc & vmalloc.
  Also, gave a small overview of MM concepts out of scope pf this session.
  Attendees asked good questions...
  - One question I got 'algo of buddy allocator'
  - Zone vs Node relation. how zone manage pages?
  - TLB flush for PTE update? entire TLB flush or just one entry
  - kmalloc/vmalloc discussion
  - What is high memory?
  - Someone asked about OOM killer and its decision criteria?

  Jeetendra asked me to can we do code walk through of any small part in coming meetups
  and I noted.

* Siddhesh, 'Amit Kucheria' and me(Pankaj) requested attendees to join mailing list. Everyone
  agreed to do regular meetup on last weekend of every month. Amit asked people to come
  up with the ideas on topic of interests. As anyone can be interested in new topics as well.
  So, different topics can be learning opportunity for everyone.
  
  - 'Nitin Bansal' agreed to present session on 'crash' debugging with example.
  - 'Jeetendra will give "session on ext filesystem in general"
  -  Amit asked me(Pankaj), can we include pending 'Networking session with QEMU/KVM' which I noted.
     As initially we are planning to have two sessions on every meetup, we will have to see
     if we can plan this for future meetups.

This is all the talk we had in the meetup. I really enjoyed attending it and enthusiasm of attendees
was awesome. I hope we will have more meetups in future and sessions to learn and share knowledge.

Thank you Guys!

Feel free to add if I missed any thing.

-----------------

Some of the my topics of interests are for future meet-ups on which i want to talk are:

* "Code walk through of any one topic of MM". Also I am interested to discuss about kVM MM internals.
* "Code walk through of any one topic of RT Kernel" or in general.
* "Overview of some of the kernel synchronization techniques or code overview of atleast one :-)"

Please share your thoughts or interested topics as well.

Best regards,
Pankaj