Per discussion on https://github.com/open-mpi/ompi/pull/1767 (and some
subsequent phone calls and off-issue email discussions), the PSM
library is hijacking signal handlers by default. Specifically: unless
the environment variables `IPATH_NO_BACKTRACE=1` (for PSM / Intel
TrueScale) is set, the library constructor for this library will
hijack various signal handlers for the purpose of invoking its own
error reporting mechanisms.
This may be a bit *surprising*, but is not a *problem*, per se. The
real problem is that older versions of at least the PSM library do not
unregister these signal handlers upon being unloaded from memory.
Hence, a segv can actually result in a double segv (i.e., the original
segv and then another segv when the now-non-existent signal handler is
invoked).
This PSM signal hijacking subverts Open MPI's own signal reporting
mechanism, which may be a bit surprising for some users (particularly
those who do not have Intel TrueScale). As such, we disable it by
default so that Open MPI's own error-reporting mechanisms are used.
Additionally, there is a typo in the library destructor for the PSM2
library that may cause problems in the unloading of its signal
handlers. This problem can be avoided by setting `HFI_NO_BACKTRACE=1`
(for PSM2 / Intel OmniPath).
This is further compounded by the fact that the PSM / PSM2 libraries
can be loaded by the OFI MTL and the usNIC BTL (because they are
loaded by libfabric), even when there is no Intel networking hardware
present. Having the PSM/PSM2 libraries behave this way when no Intel
hardware is present is clearly undesirable (and is likely to be fixed
in future releases of the PSM/PSM2 libraries).
This commit sets the following two environment variables to disable
this behavior from the PSM/PSM2 libraries (if they are not already
set):
* IPATH_NO_BACKTRACE=1
* HFI_NO_BACKTRACE=1
If the user has set these variables before invoking Open MPI, we will
not override their values (i.e., their preferences will be honored).
Signed-off-by: Jeff Squyres <jsquyres@cisco.com>
WHAT: Merge the PMIx branch into the devel repo, creating a new
OPAL “lmix” framework to abstract PMI support for all RTEs.
Replace the ORTE daemon-level collectives with a new PMIx
server and update the ORTE grpcomm framework to support
server-to-server collectives
WHY: We’ve had problems dealing with variations in PMI implementations,
and need to extend the existing PMI definitions to meet exascale
requirements.
WHEN: Mon, Aug 25
WHERE: https://github.com/rhc54/ompi-svn-mirror.git
Several community members have been working on a refactoring of the current PMI support within OMPI. Although the APIs are common, Slurm and Cray implement a different range of capabilities, and package them differently. For example, Cray provides an integrated PMI-1/2 library, while Slurm separates the two and requires the user to specify the one to be used at runtime. In addition, several bugs in the Slurm implementations have caused problems requiring extra coding.
All this has led to a slew of #if’s in the PMI code and bugs when the corner-case logic for one implementation accidentally traps the other. Extending this support to other implementations would have increased this complexity to an unacceptable level.
Accordingly, we have:
* created a new OPAL “pmix” framework to abstract the PMI support, with separate components for Cray, Slurm PMI-1, and Slurm PMI-2 implementations.
* Replaced the current ORTE grpcomm daemon-based collective operation with an integrated PMIx server, and updated the grpcomm APIs to provide more flexible, multi-algorithm support for collective operations. At this time, only the xcast and allgather operations are supported.
* Replaced the current global collective id with a signature based on the names of the participating procs. The allows an unlimited number of collectives to be executed by any group of processes, subject to the requirement that only one collective can be active at a time for a unique combination of procs. Note that a proc can be involved in any number of simultaneous collectives - it is the specific combination of procs that is subject to the constraint
* removed the prior OMPI/OPAL modex code
* added new macros for executing modex send/recv to simplify use of the new APIs. The send macros allow the caller to specify whether or not the BTL supports async modex operations - if so, then the non-blocking “fence” operation is used, if the active PMIx component supports it. Otherwise, the default is a full blocking modex exchange as we currently perform.
* retained the current flag that directs us to use a blocking fence operation, but only to retrieve data upon demand
This commit was SVN r32570.
WHAT: Open our low-level communication infrastructure by moving all necessary components (btl/rcache/allocator/mpool) down in OPAL
All the components required for inter-process communications are currently deeply integrated in the OMPI layer. Several groups/institutions have express interest in having a more generic communication infrastructure, without all the OMPI layer dependencies. This communication layer should be made available at a different software level, available to all layers in the Open MPI software stack. As an example, our ORTE layer could replace the current OOB and instead use the BTL directly, gaining access to more reactive network interfaces than TCP. Similarly, external software libraries could take advantage of our highly optimized AM (active message) communication layer for their own purpose. UTK with support from Sandia, developped a version of Open MPI where the entire communication infrastucture has been moved down to OPAL (btl/rcache/allocator/mpool). Most of the moved components have been updated to match the new schema, with few exceptions (mainly BTLs where I have no way of compiling/testing them). Thus, the completion of this RFC is tied to being able to completing this move for all BTLs. For this we need help from the rest of the Open MPI community, especially those supporting some of the BTLs. A non-exhaustive list of BTLs that qualify here is: mx, portals4, scif, udapl, ugni, usnic.
This commit was SVN r32317.
(http://www.open-mpi.org/community/lists/devel/2012/04/10905.php), set
opal_cache_line_size via hwloc data, if we have it.
opal_cache_line_size will be set to an hwloc-inspired value by the end
of orte_init(), but will always have a safe value to use (i.e., a
default value 128) -- even before opal_init() has completed.
Default to the same value of 128 that Open MPI has used for several
years if a) we have no hwloc data, or b) we weren't able to find L2
objects in the hwloc data.
This commit was SVN r26322.
#define CACHE_LINE_SIZE to 128. This name has a conflict on NetBSD,
and it seems kinda odd to have a header file that ''only'' defines a
single value. Also, we'll soon be raising hwloc to be a first-class
item, so having this file around seemed kinda weird.
Therefore, I replaced CACHE_LINE_SIZE with opal_cache_line_size, an
int (in opal/runtime/opal_init.c and opal/runtime/opal.h) on the
rationale that we can fill this in at runtime with hwloc info (trunk
and v1.5/beyond, only). The only place we ''needed'' a compile-time
CACHE_LINE_SIZE was in the BTL SM (for struct padding), so I made a
new BTL_SM_ preprocessor macro with the old CACHE_LINE_SIZE value
(128). That use isn't suitable for run-time hwloc information,
anyway.
This commit was SVN r23349.
friends also receive &argc and &argv (George asked Jeff to Ralph to
review before committing). The thought is that passing argv and argc
to opal/orte_init be useful to other projects outside of OMPI that are
using OPAL and/or ORTE (especially in conjunction with some other
bootstrapping code where it is helpful to modify argv). It's such a
small thing that it's easy to apply here to make others' lives a
little easier.
Ask George for more details; I'm just the messenger. :-)
Judging by the copyrights on this patch, it's been around for a
while. :-)
This commit was SVN r22260.
1. minor modification to include two new opal MCA params:
(a) opal_profile: outputs what components were selected by each framework
currently enabled for most, but not all, frameworks
(b) opal_profile_file: name of file that contains profile info required
for modex
2. introduction of two new tools:
(a) ompi-probe: MPI process that simply calls MPI_Init/Finalize with
opal_profile set. Also reports back the rml IP address for all
interfaces on the node
(b) ompi-profiler: uses ompi-probe to create the profile_file, also
reports out a summary of what framework components are actually
being used to help with configuration options
3. modification of the grpcomm basic component to utilize the
profile file in place of the modex where possible
4. modification of orterun so it properly sees opal mca params and
handles opal_profile correctly to ensure we don't get its profile
5. similar mod to orted as for orterun
6. addition of new test that calls orte_init followed by calls to
grpcomm.barrier
This is all completely benign unless actively selected. At the moment, it only supports modex-less launch for openib-based systems. Minor mod to the TCP btl would be required to enable it as well, if people are interested. Similarly, anyone interested in enabling other BTL's for modex-less operation should let me know and I'll give you the magic details.
This seems to significantly improve scalability provided the file can be locally located on the nodes. I'm looking at an alternative means of disseminating the info (perhaps in launch message) as an option for removing that constraint.
This commit was SVN r20098.
made in r18345 for ompi_version_string. This was done per request from Jeff
Squyres to maintain consistency and to remove some warnings caused by the
non-use of some static const char.
This commit was SVN r18461.
The following SVN revision numbers were found above:
r18345 --> open-mpi/ompi@8dd0421015
This commit moves the initalization/finalization of opal_event and opal_progress
to opal_init/finalize. These were previously init/final in ORTE which is an
abstraction violation. After talking about it we concluded that there are no
ordering issues that require these to be init/final in ORTE instead of OPAL.
I ran the IBM test suite against this commit and it didn't turn up any new
failures so I think it is good to go.
Let us know if this causes problems.
This commit was SVN r14773.
This merge adds Checkpoint/Restart support to Open MPI. The initial
frameworks and components support a LAM/MPI-like implementation.
This commit follows the risk assessment presented to the Open MPI core
development group on Feb. 22, 2007.
This commit closes trac:158
More details to follow.
This commit was SVN r14051.
The following SVN revisions from the original message are invalid or
inconsistent and therefore were not cross-referenced:
r13912
The following Trac tickets were found above:
Ticket 158 --> https://svn.open-mpi.org/trac/ompi/ticket/158
different macros, one for each project. Therefore, now we have OPAL_DECLSPEC,
ORTE_DECLSPEC and OMPI_DECLSPEC. Please use them based on the sub-project.
This commit was SVN r11270.
- move files out of toplevel include/ and etc/, moving it into the
sub-projects
- rather than including config headers with <project>/include,
have them as <project>
- require all headers to be included with a project prefix, with
the exception of the config headers ({opal,orte,ompi}_config.h
mpi.h, and mpif.h)
This commit was SVN r8985.
r8698), with changes below:
- Split wrapper flags into those required for each of the three projects,
and cleaned up some cruft (including the LIBMPI_EXTRA_*FLAGS) through-
out the build system
- Added opal_init_util and opal_finalize_util to allow init / cleanup
of all the opal code that doesn't require the MCA system
- Create standalone key=value file parser, based on the one that used
to be in the mca param parser, so that it can be shared in multiple
places
- Add wrapper datafiles for opal, orte, and ompi wrappers, and add
wrapper compiler with support for all the old features
This commit was SVN r8699.
The following SVN revisions from the original message are invalid or
inconsistent and therefore were not cross-referenced:
r8690
r8698
