freebsd-dev/share
Adrian Chadd 6520495abc Add an initial NUMA affinity/policy configuration for threads and processes.
This is based on work done by jeff@ and jhb@, as well as the numa.diff
patch that has been circulating when someone asks for first-touch NUMA
on -10 or -11.

* Introduce a simple set of VM policy and iterator types.
* tie the policy types into the vm_phys path for now, mirroring how
  the initial first-touch allocation work was enabled.
* add syscalls to control changing thread and process defaults.
* add a global NUMA VM domain policy.
* implement a simple cascade policy order - if a thread policy exists, use it;
  if a process policy exists, use it; use the default policy.
* processes inherit policies from their parent processes, threads inherit
  policies from their parent threads.
* add a simple tool (numactl) to query and modify default thread/process
  policities.
* add documentation for the new syscalls, for numa and for numactl.
* re-enable first touch NUMA again by default, as now policies can be
  set in a variety of methods.

This is only relevant for very specific workloads.

This doesn't pretend to be a final NUMA solution.

The previous defaults in -HEAD (with MAXMEMDOM set) can be achieved by
'sysctl vm.default_policy=rr'.

This is only relevant if MAXMEMDOM is set to something other than 1.
Ie, if you're using GENERIC or a modified kernel with non-NUMA, then
this is a glorified no-op for you.

Thank you to Norse Corp for giving me access to rather large
(for FreeBSD!) NUMA machines in order to develop and verify this.

Thank you to Dell for providing me with dual socket sandybridge
and westmere v3 hardware to do NUMA development with.

Thank you to Scott Long at Netflix for providing me with access
to the two-socket, four-domain haswell v3 hardware.

Thank you to Peter Holm for running the stress testing suite
against the NUMA branch during various stages of development!

Tested:

* MIPS (regression testing; non-NUMA)
* i386 (regression testing; non-NUMA GENERIC)
* amd64 (regression testing; non-NUMA GENERIC)
* westmere, 2 socket (thankyou norse!)
* sandy bridge, 2 socket (thankyou dell!)
* ivy bridge, 2 socket (thankyou norse!)
* westmere-EX, 4 socket / 1TB RAM (thankyou norse!)
* haswell, 2 socket (thankyou norse!)
* haswell v3, 2 socket (thankyou dell)
* haswell v3, 2x18 core (thankyou scott long / netflix!)

* Peter Holm ran a stress test suite on this work and found one
  issue, but has not been able to verify it (it doesn't look NUMA
  related, and he only saw it once over many testing runs.)

* I've tested bhyve instances running in fixed NUMA domains and cpusets;
  all seems to work correctly.

Verified:

* intel-pcm - pcm-numa.x and pcm-memory.x, whilst selecting different
  NUMA policies for processes under test.

Review:

This was reviewed through phabricator (https://reviews.freebsd.org/D2559)
as well as privately and via emails to freebsd-arch@.  The git history
with specific attributes is available at https://github.com/erikarn/freebsd/
in the NUMA branch (https://github.com/erikarn/freebsd/compare/local/adrian_numa_policy).

This has been reviewed by a number of people (stas, rpaulo, kib, ngie,
wblock) but not achieved a clear consensus.  My hope is that with further
exposure and testing more functionality can be implemented and evaluated.

Notes:

* The VM doesn't handle unbalanced domains very well, and if you have an overly
  unbalanced memory setup whilst under high memory pressure, VM page allocation
  may fail leading to a kernel panic.  This was a problem in the past, but it's
  much more easily triggered now with these tools.

* This work only controls the path through vm_phys; it doesn't yet strongly/predictably
  affect contigmalloc, KVA placement, UMA, etc.  So, driver placement of memory
  isn't really guaranteed in any way.  That's next on my plate.

Sponsored by:	Norse Corp, Inc.; Dell
2015-07-11 15:21:37 +00:00
..
colldef Add META_MODE support. 2015-06-13 19:20:56 +00:00
dict Add META_MODE support. 2015-06-13 19:20:56 +00:00
doc Readd merge.awk forgotten while importing the old vi documentation directly into 2015-06-20 00:13:28 +00:00
dtrace Add missing DTrace scripts that exist in the source tree to the Makefile for 2015-06-30 18:23:08 +00:00
examples Add missing shebang 2015-07-04 02:24:47 +00:00
i18n new depends 2015-06-16 23:37:19 +00:00
keys Remove scary comment about this being a test key. 2014-01-13 20:55:15 +00:00
man Add an initial NUMA affinity/policy configuration for threads and processes. 2015-07-11 15:21:37 +00:00
me Add META_MODE support. 2015-06-13 19:20:56 +00:00
misc Add myself to committers-src.dot 2015-07-08 03:20:28 +00:00
mk Fix typo which breaks build of manpages when WITHOUT_MANCOMPRESS is set 2015-07-08 22:24:55 +00:00
mklocale Add META_MODE support. 2015-06-13 19:20:56 +00:00
monetdef Add META_MODE support. 2015-06-13 19:20:56 +00:00
msgdef Add META_MODE support. 2015-06-13 19:20:56 +00:00
numericdef Add META_MODE support. 2015-06-13 19:20:56 +00:00
security Add META_MODE support. 2015-06-13 19:20:56 +00:00
sendmail Add META_MODE support. 2015-06-13 19:20:56 +00:00
skel Add META_MODE support. 2015-06-13 19:20:56 +00:00
snmp Add META_MODE support. 2015-06-13 19:20:56 +00:00
syscons Add META_MODE support. 2015-06-13 19:20:56 +00:00
tabset Add META_MODE support. 2015-06-13 19:20:56 +00:00
termcap Add META_MODE support. 2015-06-13 19:20:56 +00:00
tests Add some sample test programs. 2013-11-18 12:57:46 +00:00
timedef Add META_MODE support. 2015-06-13 19:20:56 +00:00
vt kbdmap(1): Correct menu title: keyboards have a layout, not a language 2015-05-14 18:09:56 +00:00
zoneinfo Add META_MODE support. 2015-06-13 19:20:56 +00:00
Makefile Only build share/dtrace if MK_CDDL != no 2015-01-25 00:32:17 +00:00
Makefile.inc