Minutes of Conference Call 8/15/05

[Kevin Stafford <kevinrs at us dot ibm dot com>]

Minutes of SystemTap Conference Call, Sept. 15, 2005

Participants:
IBM:
       Ananth Mavinakayanahalli (mananth@in.ibm.com -- Boston)
       Jim Keniston (jkenisto@us.ibm.com -- Beaverton)
       Hien Nguyen (nguyhien@us.ibm.com -- Beaverton)
       Kevin Stafford (kevinrs@us.ibm.com -- Beaverton)
       Prasanna Panchamukhi (prasanna@in.ibm.com -- Bangalore)
       Maneesh Soni (maneesh@in.ibm.com -- Bangalore)
       Tom Zanussi (trz@us.ibm.com -- Chicago)
Red Hat:
       Will Cohen (wcohen@redhat.com -- Raleigh)
       Martin Hunt (hunt@redhat.com -- Seattle)
       Graydon Hoare (graydon@redhat.com -- Vancouver)
Intel:
       Anil KeshavaMurthy (anil.s.keshavamurthy@intel.com -- Hillsboro)
       Josh Stone
Hitachi:
       Satoshi Oshima (soshima@redhat.com)

Actions Required (ARs):
>From 5/19/05:
19. Vara: Collect sample kprobes modules and post them to the
SystemTap web site.

22. Rusty: Look into x86_64 limitation re: temporary disarming of
reentrant probes.

23. Jim, Martin: Ensure that the runtime's stack-trace feature works
appropriately when there are return probes in the call stack.
[Update: Martin is working on this.  Jim will prototype an improvement
whereby the saved IP is updated before the handler is called.]

>From 6/9/05:
26. Rusty/Brad: Forward email address of Intel test person to Jay
Turner.  [Update: As of 7/7/05, Brad hasn't done this.  Did Rusty?]

>From 6/23/05:
30. Rusty: Review Will's rendition of Rusty's test that exercises
probes on a wide variety of instruction types.  [Update: As of 7/7/05,
Will still needs to hear back from Rusty.]

>From 7/7/05:
39. Ananth: Summarize the status of the ppc64 runtime port for Martin.
[Update 8/17/05: Jose Santos of the IBM pSeries performance team will
complete the port.]

>From 7/28/05:
41. Anil: Post a summary of known djprobes implementation issues.

>From 8/4/05:
43. Prasanna: Post work on user-space probes.  [Update: Design is
under review at IBM.  This is deferred until after current SystemTap
test/debug push.]

>From 8/11/05:
44. Tom: Automate relayfs tests and post them to mailing list.
[Update: In progress]

>From 8/18/05:
48. Elena, Vara: Manage planning of next face-to-face meeting.

50. Jim: Characterize the problem(s) we've seen when probing
schedule().  [DONE: #1229 is fixed by Ananth and Anil.]

53. Anil: Test RCU-based SMP scalability feature on ia64.

>From 8/25/05:
54. Vara: Report on availability of tech writer(s) at IBM to help
with user documentation.

55. Elena: Investigate approaches to making the full SystemTap bug
list available to SystemTap developers outside Red Hat.i

>From 9/8/05:

56. Will: Integate RH testsuite as part of std distro tests (rather
than local system testing).

57. Martin: Runtime build issues fix.

58. Ananth: Work on resolving PPC64 runtime issues.

59: Elena: Send out editable OLS slides

60: Will: Check into CVS - htdocs

61: Kevin: Post FC4 SystemTap installation instructions.

Translator freeze is set for end of next week (9/16).

RH team is continuing work on resolving translator bugs.

The Runtime has build errors, Martin will look into a fix.

Ananth is taking over work on the PPC64 shortcomings:
       -runtime problems
       -elfutils (dot prefix)

Anil will start ia64 testing this week.

SystemTap Installation:
       casual fc4 users simply "yum update systemtap"
       developers: Kevin will post howto doc to build
                   SystemTap from src.

       RHEL4 users: "up2date systemtap"

Insufficient debug info breaks some core functionalities
when running a stock kernel.
Possible fix: use -g option (make cflags+=-g or make -g)

perfmon/perfctr wars are over. Api controversy is settled:
Michael would like to go forward with perfmon.

See CVS for new SystemTap samples.

>From 9/15/05:

62. SystemTap priorities: continue to fix/report bugs & check tests into 
CVS.
   Tests are located in seperate test module in CVS.

63. Martin to post howto mail on running the test module from CVS to 
SystemTap
   ML.

64. Dj probes patches to be posted to SystemTap ML for review. Upon feedback
   Satoshi wishes to submit upstream.

65. Prasanna posted userspace probes document, and is awaiting feedback.

66. Ananth requests testing per-cpu locking patches on SMP machines using
   lmbench. (Prasanna will post benchmarks on 32-way machine.) Based on
   these results will post to LKML.

67. Andrew suggests moving kprobes from kernel hacking to new home, possibly
   profiling. Vara to send mail to oprofile/perfmon groups about merging.

70. Prasanna to post working userspace probes patches to ML.

71. Hien will test RCU patches on 4x PPC64 machine, post results to ML.

72. Jim to post user-space return probes design document. Awaits feedback.

--
Kevin Stafford
DES 2 | MS 2M3
Beaverton - OR
Linux Technology Center
IBM Systems & Technology
Phone: 1-503-578-3039
Email: kevinrs@us.ibm.com