WeeklyTelcon_20160412

Open MPI Weekly Telcon

---

• Dialup Info: (Do not post to public mailing list or public wiki)

Attendees

• Geoff Paulsen
• Jeff Squyres
• Edgar Gabriel
• Howard
• Josh Hursey
• Joshua Ladd
• Nathan Hjelm
• Ralph Castain
• Ryan Grant
• Sylvain Jeaugey
• Todd Kordenbrock

---

Agenda

Review 1.10

• Milestones: https://github.com/open-mpi/ompi-release/milestones/v1.10.3

  • Ralph will look at the ByNode thing today.
  • Allena reported a SLURM issue.
  • Issue 1530 Reason MTT was hanging was due to a test signal handler segving, cores taking a long time to dump.
  • Next 1.10 release. need to fix these issues, but looking like early May.

• Github Now DOES allow per-branch permissions, so will look at

Review 2.0.x

• Wiki: https://github.com/open-mpi/ompi/wiki/Releasev20

• Blocker Issues: https://github.com/open-mpi/ompi/issues?utf8=%E2%9C%93&q=is%3Aopen+milestone%3Av2.0.0+label%3Ablocker

  • 1 remaining blocker: to memory symbol patcher - Nathan / IBM / Mellanox.
    • Got the original code to stack with UCX. munmap on Linux has an optional argument. This doesn't work well with any style of hooking. Loader ends up patching a random function address. Didn't understand. Assembly looked okay, but munmap was randomly
    • When UCX is involved, seeing both Open MPI and UCX memhooks, which is great.
    • SPARC still having issues, so will need a solution for 2.0.1.
    • Nathan will work to remove ptmalloc on master, and have build time
    • on 2.0.0 Nathan will add a --enable-ptmalloc explicit configure option, but doesn't build by default.
      • If users configure --enable-ptmalloc, then it would disable the internal memhook frameworks entirely.
      • when this happens, will have to add some early code to tickle ptmalloc
      • need to document that if --enable-ptmalloc then munmap() calls may give wrong answers.
    • Nathan might due sparc assembly himself, since seeing weird dlsym issues on sparc, that might be related.
    • Now created first time creating an rcache.
    • Might need to tweak openib BTL, because it created rcache too early.
    • When you create a thread, it has to expand the heap sometimes.
    • When they expand heap, they protect entire heap with PROT_NOTE.
    • munmap, mremap (if new length is smaller than old length), shmdt (only on linux, not OSX), brk.
      • need sbrk also (for negative increment).
    • Nathan will look at README for memory hook stuff.
    • OPENFABRICS should get it's act together and put in something in kernel to alleviate ll of this.
  • Question, do we want new prettier ompi_info output. Didn't change parsable output.
    • Low risk, got contributor agreement (works for SuSE). Can pull 1515, 1516, 1518 into 2.0.

• Milestones: https://github.com/open-mpi/ompi-release/milestones/v2.0.0 *

Review Master?

• Absoft failure. Need to fix configure stuff with atomics. On Master.
• Nathan - this failure should go into 2.0.1. Absoft MTT shows that

MTT status:

• IBM has a client facing cluster
  • Working on getting Jenkins setup on IBM side to ensure Pull Requests get tested on Power also.
  • Hoping to have online this week?
• Better upload interface using by both Ralph and Josh.
• Plugins to support SLURM, Copy tree, Shell commands. Compiler version detection.
• Looking at establishing MTT release .tarballs.
• Timeframe: Sooner rather than later

Status Updates:

1. Cisco - a bunch of release engineering work for both libfabric and OMPI.
   • assisting on a number of bugs.
2. NVIDIA - Sylvian - An issue on MTT - looking into.

---

Status Update Rotation

1. Cisco, ORNL, UTK, NVIDIA
2. Mellanox, Sandia, Intel
3. LANL, Houston, IBM

---

Back to 2016 WeeklyTelcon-2016