variables that are not initialized and are declared in a file that
doesn't export any globally visible function are marked as
non-initialized constants, i.e. uninitialized common symbols. For some
obscure reasons, they get removed from the object files on Mac OS X.
So far I found two solution to this problem. One require the addition
of "-c" to the linker command, the second one (corresponding to this
patch) force them to became a common initialized symbol.
This commit was SVN r21739.
in this directory and it's causing "make dist" to break.
Shiqing -- is there a missing file in this directory? If so, please
add it and restore the EXTRA_DIST line I just removed. Thanks!
This commit was SVN r21340.
Add a new tm ess module that exploits this capability.
Update the various plm modules to enable it - just a minor change reflecting an added param to a plm base function.
Additional fixes included:
1. remove an erroneous cleanup of session directories in the tool finalize procedure - tools don't create session directories to begin with!
2. fix a duplicate free when attempting to execute a non-existent app
3. cleanup an typo in the comm utilities
4. fix comm_spawn - was perturbed by the changes in pack/unpack of orte_job_t to properly support orte-ps
Been tested on slurm and tm machines, using all tests in orte/test/mpi. May run into issue with command line length on large jobs due to inclusion of node info to support static ports - will fix this next with addition of regexp generator to compress that info.
This commit was SVN r21248.
This causes the orteds in the routing tree to remain alive until all termination "acks" from orteds below them have passed through. Thus, if we use static ports, we no longer require a direct orted-to-mpirun connection.
Also modify the binomial routed module so it conforms to what all the other routed modules do and have all messages pass along the routing tree instead of short-circuiting between orteds. This further reduces the number of ports being opened on backend nodes.
This commit was SVN r21203.
- Delete unnecessary header files using
contrib/check_unnecessary_headers.sh after applying
patches, that include headers, being "lost" due to
inclusion in one of the now deleted headers...
In total 817 files are touched.
In ompi/mpi/c/ header files are moved up into the actual c-file,
where necessary (these are the only additional #include),
otherwise it is only deletions of #include (apart from the above
additions required due to notifier...)
- To get different MCAs (OpenIB, TM, ALPS), an earlier version was
successfully compiled (yesterday) on:
Linux locally using intel-11, gcc-4.3.2 and gcc-SVN + warnings enabled
Smoky cluster (x86-64 running Linux) using PGI-8.0.2 + warnings enabled
Lens cluster (x86-64 running Linux) using Pathscale-3.2 + warnings enabled
This commit was SVN r21096.
In case we use memcmp, strlen, strup and friends include <string.h>
Also several constants.h are not included directly
- Let's have mca_topo_base_cart_create return ompi-errors in
ompi/mca/topo/base/topo_base_cart_create.c
This commit was SVN r20773.
Adapt orte_process_info to orte_proc_info, and
change orte_proc_info() to orte_proc_info_init().
- Compiled on linux-x86-64
- Discussed with Ralph
This commit was SVN r20739.
get bitten by header depending on having already included
the corresponding [opal|orte|ompi]_config.h header.
When separating, things like [OPAL|ORTE|OMPI]_DECLSPEC
are missed.
Script to add the corresponding header in front of all following
(taking care of possible #ifdef HAVE_...)
- Including some minor cleanups to
- ompi/group/group.h -- include _after_ #ifndef OMPI_GROUP_H
- ompi/mca/btl/btl.h -- nclude _after_ #ifndef MCA_BTL_H
- ompi/mca/crcp/bkmrk/crcp_bkmrk_btl.c -- still no need for
orte/util/output.h
- ompi/mca/pml/dr/pml_dr_recvreq.c -- no need for mpool.h
- ompi/mca/btl/btl.h -- reorder to fit
- ompi/mca/bml/bml.h -- reorder to fit
- ompi/runtime/ompi_mpi_finalize.c -- reorder to fit
- ompi/request/request.h -- additionally need ompi/constants.h
- Tested on linux/x86-64
This commit was SVN r20720.
Note: this requires that nodes not be shared by jobs/users. SLURM developers are working on an enhancement to remove this constraint.
Note 2: yes, the direct routed module returned! However, it is vastly different than the old one and has zero support for such things as comm_spawn. It is solely to support non-daemon, direct-launch environments.
This commit was SVN r20601.
Often, orte/util/show_help.h is included, although no functionality
is required -- instead, most often opal_output.h, or
orte/mca/rml/rml_types.h
Please see orte_show_help_replacement.sh commited next.
- Local compilation (Linux/x86_64) w/ -Wimplicit-function-declaration
actually showed two *missing* #include "orte/util/show_help.h"
in orte/mca/odls/base/odls_base_default_fns.c and
in orte/tools/orte-top/orte-top.c
Manually added these.
Let's have MTT the last word.
This commit was SVN r20557.
y combination of comma-separated values and ranges. Daemons will use the first port in the range, MPI procs will use the other ports in the range assuming that they know their node rank in time and enough ports were specified.
NOTE: this capability only works under specific conditions. I will outline more about this in a note to devel as the remainder of the implementation progresses. For now, the only environment where this works is slurm. The linear routed module has also been adjusted to work with static ports so that all messaging flows strictly through the topology, including the initial daemon callback - thus limiting the number of sockets opened by mpirun.
This commit was SVN r20390.
This commit does that by ensuring that daemons retain knowledge of proc location for all procs in their job family. It required a minor change to the ESS API to allow the daemons to update their pidmaps as data was received. In addition, the routed modules have been updated to take advantage of the newly available info, and the encode/decode pidmap utilities have been updated to communicate the required info in the launch message.
This commit was SVN r20022.
1. register "mpi_preconnect_all" as a deprecated synonym for "mpi_preconnect_mpi"
2. remove "mpi_preconnect_oob" and "mpi_preconnect_oob_simultaneous" as these are no longer valid.
3. remove the routed framework's "warmup_routes" API. With the removal of the direct routed component, this function at best only wasted communications. The daemon routes are completely "warmed up" during launch, so having MPI procs order the sending of additional messages is simply wasteful.
4. remove the call to orte_routed.warmup_routes from MPI_Init. This was the only place it was used anyway.
The FAQs will be updated to reflect this changed situation, and a CMR filed to move this to the 1.3 branch.
This commit was SVN r19933.
1. remove direct routed module (hooray!)
2. add radix tree routed module (binomial remains default)
3. remove duplicate data storage - orteds were storing nidmap and pidmap data in odls, everyone else in ess
4. add ess APIs to update nidmap, add new pidmap - used only by orteds for MPI-2 support
5. modify code to eliminate multiple calls to orte_routed.update_route that recreated info already in ess pidmap. Add ess API to lookup that info instead. Modify routed modules to utilize that capability
6. setup new ability to shutdown orteds without sending back an "ack" message to mpirun - not utilized yet, will require some changes to plm terminate_orteds functions in managed environments (coming soon)
Initial tests indicating that fully routing comm via defined routing trees may not actually have a significant cost for operations like IB QP setup. More tests required to confirm.
This will require an autogen...
This commit was SVN r19866.
Refers to ticket #1548. Although this appears to fix the problem, the ticket will be held open pending further test prior to transition to the 1.3 branch.
This commit was SVN r19674.
* add "register" function to mca_base_component_t
* converted coll:basic and paffinity:linux and paffinity:solaris to
use this function
* we'll convert the rest over time (I'll file a ticket once all
this is committed)
* add 32 bytes of "reserved" space to the end of mca_base_component_t
and mca_base_component_data_2_0_0_t to make future upgrades
[slightly] easier
* new mca_base_component_t size: 196 bytes
* new mca_base_component_data_2_0_0_t size: 36 bytes
* MCA base version bumped to v2.0
* '''We now refuse to load components that are not MCA v2.0.x'''
* all MCA frameworks versions bumped to v2.0
* be a little more explicit about version numbers in the MCA base
* add big comment in mca.h about versioning philosophy
This commit was SVN r19073.
The following Trac tickets were found above:
Ticket 1392 --> https://svn.open-mpi.org/trac/ompi/ticket/1392
1. add a new API delete_route(orte_process_name_t*) to delete the specified proc from the routing table
2. modify update_route so that it actually updates pre-existing routes instead of only adding routing info the end of the hash table
This fixes ticket #1403
This commit was SVN r18970.
1. repair of the linear and direct routed modules
2. repair of the ompi/pubsub/orte module to correctly init routes to the ompi-server, and correctly handle failure to correctly parse the provided ompi-server URI
3. modification of orterun to accept both "file" and "FILE" for designating where the ompi-server URI is to be found - purely a convenience feature
4. resolution of a message ordering problem during the connect/accept handshake that allowed the "send-first" proc to attempt to send to the "recv-first" proc before the HNP had actually updated its routes.
Let this be a further reminder to all - message ordering is NOT guaranteed in the OOB
5. Repair the ompi/dpm/orte module to correctly init routes during connect/accept.
Reminder to all: messages sent to procs in another job family (i.e., started by a different mpirun) are ALWAYS routed through the respective HNPs. As per the comments in orte/routed, this is REQUIRED to maintain connect/accept (where only the root proc on each side is capable of init'ing the routes), allow communication between mpirun's using different routing modules, and to minimize connections on tools such as ompi-server. It is all taken care of "under the covers" by the OOB to ensure that a route back to the sender is maintained, even when the different mpirun's are using different routed modules.
6. corrections in the orte/odls to ensure proper identification of daemons participating in a dynamic launch
7. corrections in build/nidmap to support update of an existing nidmap during dynamic launch
8. corrected implementation of the update_arch function in the ESS, along with consolidation of a number of ESS operations into base functions for easier maintenance. The ability to support info from multiple jobs was added, although we don't currently do so - this will come later to support further fault recovery strategies
9. minor updates to several functions to remove unnecessary and/or no longer used variables and envar's, add some debugging output, etc.
10. addition of a new macro ORTE_PROC_IS_DAEMON that resolves to true if the provided proc is a daemon
There is still more cleanup to be done for efficiency, but this at least works.
Tested on single-node Mac, multi-node SLURM via odin. Tests included connect/accept, publish/lookup/unpublish, comm_spawn, comm_spawn_multiple, and singleton comm_spawn.
Fixes ticket #1256
This commit was SVN r18804.
This commit ensures that attempts to access information that is unknowable or undefined returns appropriate invalid or not_supported values to avoid unexpected behavior and/or segfaults.
This commit was SVN r18692.
Some minor changes to help facilitate debugger support so that both mpirun and yod can operate with it. Still to be completed.
This commit was SVN r18664.
After much work by Jeff and myself, and quite a lot of discussion, it has become clear that we simply cannot resolve the infinite loops caused by RML-involved subsystems calling orte_output. The original rationale for the change to orte_output has also been reduced by shifting the output of XML-formatted vs human readable messages to an alternative approach.
I have globally replaced the orte_output/ORTE_OUTPUT calls in the code base, as well as the corresponding .h file name. I have test compiled and run this on the various environments within my reach, so hopefully this will prove minimally disruptive.
This commit was SVN r18619.
such, the commit message back to the master SVN repository is fairly
long.
= ORTE Job-Level Output Messages =
Add two new interfaces that should be used for all new code throughout
the ORTE and OMPI layers (we already make the search-and-replace on
the existing ORTE / OMPI layers):
* orte_output(): (and corresponding friends ORTE_OUTPUT,
orte_output_verbose, etc.) This function sends the output directly
to the HNP for processing as part of a job-specific output
channel. It supports all the same outputs as opal_output()
(syslog, file, stdout, stderr), but for stdout/stderr, the output
is sent to the HNP for processing and output. More on this below.
* orte_show_help(): This function is a drop-in-replacement for
opal_show_help(), with two differences in functionality:
1. the rendered text help message output is sent to the HNP for
display (rather than outputting directly into the process' stderr
stream)
1. the HNP detects duplicate help messages and does not display them
(so that you don't see the same error message N times, once from
each of your N MPI processes); instead, it counts "new" instances
of the help message and displays a message every ~5 seconds when
there are new ones ("I got X new copies of the help message...")
opal_show_help and opal_output still exist, but they only output in
the current process. The intent for the new orte_* functions is that
they can apply job-level intelligence to the output. As such, we
recommend that all new ORTE and OMPI code use the new orte_*
functions, not thei opal_* functions.
=== New code ===
For ORTE and OMPI programmers, here's what you need to do differently
in new code:
* Do not include opal/util/show_help.h or opal/util/output.h.
Instead, include orte/util/output.h (this one header file has
declarations for both the orte_output() series of functions and
orte_show_help()).
* Effectively s/opal_output/orte_output/gi throughout your code.
Note that orte_output_open() takes a slightly different argument
list (as a way to pass data to the filtering stream -- see below),
so you if explicitly call opal_output_open(), you'll need to
slightly adapt to the new signature of orte_output_open().
* Literally s/opal_show_help/orte_show_help/. The function signature
is identical.
=== Notes ===
* orte_output'ing to stream 0 will do similar to what
opal_output'ing did, so leaving a hard-coded "0" as the first
argument is safe.
* For systems that do not use ORTE's RML or the HNP, the effect of
orte_output_* and orte_show_help will be identical to their opal
counterparts (the additional information passed to
orte_output_open() will be lost!). Indeed, the orte_* functions
simply become trivial wrappers to their opal_* counterparts. Note
that we have not tested this; the code is simple but it is quite
possible that we mucked something up.
= Filter Framework =
Messages sent view the new orte_* functions described above and
messages output via the IOF on the HNP will now optionally be passed
through a new "filter" framework before being output to
stdout/stderr. The "filter" OPAL MCA framework is intended to allow
preprocessing to messages before they are sent to their final
destinations. The first component that was written in the filter
framework was to create an XML stream, segregating all the messages
into different XML tags, etc. This will allow 3rd party tools to read
the stdout/stderr from the HNP and be able to know exactly what each
text message is (e.g., a help message, another OMPI infrastructure
message, stdout from the user process, stderr from the user process,
etc.).
Filtering is not active by default. Filter components must be
specifically requested, such as:
{{{
$ mpirun --mca filter xml ...
}}}
There can only be one filter component active.
= New MCA Parameters =
The new functionality described above introduces two new MCA
parameters:
* '''orte_base_help_aggregate''': Defaults to 1 (true), meaning that
help messages will be aggregated, as described above. If set to 0,
all help messages will be displayed, even if they are duplicates
(i.e., the original behavior).
* '''orte_base_show_output_recursions''': An MCA parameter to help
debug one of the known issues, described below. It is likely that
this MCA parameter will disappear before v1.3 final.
= Known Issues =
* The XML filter component is not complete. The current output from
this component is preliminary and not real XML. A bit more work
needs to be done to configure.m4 search for an appropriate XML
library/link it in/use it at run time.
* There are possible recursion loops in the orte_output() and
orte_show_help() functions -- e.g., if RML send calls orte_output()
or orte_show_help(). We have some ideas how to fix these, but
figured that it was ok to commit before feature freeze with known
issues. The code currently contains sub-optimal workarounds so
that this will not be a problem, but it would be good to actually
solve the problem rather than have hackish workarounds before v1.3 final.
This commit was SVN r18434.
Make it all work with comm_spawn in the case of all procs on previously occupied nodes, some new procs on new nodes, and mixtures of the two.
Note: comm_spawn now works with both binomial and linear routed modules. There remains a problem of spawned procs not properly getting updated contact info for the parent proc when run in the direct routed mode...but that's for another day.
This commit was SVN r18385.
http://www.open-mpi.org/community/lists/devel/2008/04/3779.php
{{{
svn merge -r 18276:18380 https://svn.open-mpi.org/svn/ompi/tmp-public/jjh-mca-play .
}}}
Any components not in the trunk, but in one of the effected frameworks *must* be
updated. Contact the list, look at the RFC, or look at the diff for how to do this.
Sorry for the early commit of this, but I wanted to get it in today (per RFC) and
didn't know if I would have a chance later today.
This commit was SVN r18381.
Modify grpcomm xcast so it now uses the selected routed module - eliminates cross-wiring of xcast and routing paths. Suboptimal at the moment, but better implementation is on its way.
Cleanup ignore properties on the new routed components.
This commit was SVN r18377.
Add two new API's to the routed framework - stub them out so that collaborators can work on them in various components without conflicts.
Remove a "finalize" from the select function that could cause problems as the component had not had its initialize called yet.
This commit was SVN r18369.
Update the rsh tree spawn capability so we spawn the next wave of daemons before launching our own local procs.
Add an ability to encode nodenames for large clusters with contiguous node name numbering schemes - this allows communication of all node names in a few bytes instead of tens-of-bytes/node.
This commit was SVN r18338.
{{{
svn merge -r 18218:18240 https://svn.open-mpi.org/svn/ompi/tmp/jjh-scratch .
}}}
Contains:
* Primarily a fix for a user reported problem where a cached file descriptor is causing a SIGPIPE on restart.
* Cleanup some small memory leaks from using mca_base_param_env_var() - Thanks Jeff
* Cleanup ORTE FT tool compilation in non-FT builds - Thanks Tim P.
* Cleanup mpi interface with missplaced {{{OPAL_CR_ENTER_LIBRARY}}} - Thanks Terry
* Some other sundry cleanup items all dealing with C/R functionality in the trunk.
This commit was SVN r18241.
Event uninit_use: Using uninitialized value "rc"
Instead of initializing rc in the beginning, rather use return value
of opal_hash_table_set_value_uint32.
This commit was SVN r17976.
Specifically, add two new APIs:
1. lost_route: allows the OOB to report that a connection has failed, thereby giving the routed module an opportunity to respond appropriately to its topology. Creating the API also allows each routed component to hold its own definition of "lifeline" - in some cases, this may be a single connection, but in others it may be multiple connections. Some modules may choose to re-route messaging if the lifeline or any other connection is lost, while others may choose to abort the job.
Both the tree and unity modules retain the current behavior and abort the job if the lifeline connection is lost, while ignoring other lost connections.
2. get_wireup_info: returns (in a provided buffer) info required to wireup connections for the specified job. Some routed modules do not need to return any info as they can wireup via alternative means, while some need to xchg data with their peers. If info is inserted into the buffer, the plm_base_launch_apps function will xcast the contents to the specified job.
The commit also removes the "lifeline" entry from the orte_process_info struct (and the associated ORTE_PROC_MY_LIFELINE definition) as the lifeline info is now contained within the respective routed module.
This commit was SVN r17969.
Ensure that direct xcast handles all its use-cases correctly.
Unity routed component needs to use the base recv function to properly operate.
This commit was SVN r17764.
This commit adds definition for a "lifeline" connection. For an HNP, there is no lifeline, so the lifeline proc is NULL. For a daemon, the lifeline is the HNP - the daemon should abort if it loses that connection.
For a proc using unity routed, the lifeline is the HNP since it connects directly to the HNP.
For a proc using tree routed, the lifeline is the local daemon.
Adjusted OOB to call abort if the lifeline (as opposed to HNP) connection is lost.
This commit was SVN r17761.
Basically, the method employed here is to have a recv create a zero-time timer event that causes the event library to execute a function that processes the message once the recv returns. Thus, any action taken as a result of processing the message occur outside of a recv.
Created two new macros to assist:
ORTE_MESSAGE_EVENT: creates the zero-time event, passing info in a new orte_message_event_t object
ORTE_PROGRESSED_WAIT: while waiting for specified conditions, just calls progress so messages can be recv'd.
Also fixed the failed_launch function as we no longer block in the orted callback function. Updated the error messages to reflect revision. No change in API to this function, but PLM "owners" may want to check their internal error messages to avoid duplication and excessive output.
This has been tested on Mac, TM, and SLURM.
This commit was SVN r17647.
about linkers, have all OPAL, ORTE, and OMPI components '''not'' link
against the OPAL, ORTE, or OMPI libraries.
See ttp://www.open-mpi.org/community/lists/users/2007/10/4220.php for
details (or https://svn.open-mpi.org/trac/ompi/wiki/Linkers for a
better-formatted version of the same info).
This commit was SVN r16968.
Note that this means ALL procs in the parent job are updated, even though they may not be participating in the comm_spawn. This doesn't really hurt anything - just unnecessary.
Comm_spawn still has a problem when a child process shares a node with a parent, so this doesn't fix everything. It only fixes the bug of ensuring all procs know how to talk to each other.
This commit was SVN r16460.
1. taking advantage of the fact that we no longer create the launch message via a GPR trigger. In earlier times, we had the GPR create the launch message based on a subscription. In that mode of operation, we could not guarantee the order in which the data was stored in the message - hence, we had no choice but to parse the message in a loop that checked each value against a list of possible "keys" until the corresponding value was found.
Now, however, we construct the message "by hand", so we know precisely what data is in each location in the message. Thus, we no longer need to send the character string "keys" for each data value any more. This represents a rather large savings in the message size - to give you an example, we typically would use a 30-char "key" for a 2-byte data value. As you can see, the overhead can become very large.
2. sending node-specific data only once. Again, because we used to construct the message via subscriptions that were done on a per-proc basis, the data for each node (e.g., the daemon's name, whether or not the node was oversubscribed) would be included in the data for each proc. Thus, the node-specific data was repeated for every proc.
Now that we construct the message "by hand", there is no reason to do this any more. Instead, we can insert the data for a specific node only once, and then provide the per-proc data for that node. We therefore not only save all that extra data in the message, but we also only need to parse the per-node data once.
The savings become significant at scale. Here is a comparison between the revised trunk and the trunk prior to this commit (all data was taken on odin, using openib, 64 nodes, unity message routing, tested with application consisting of mpi_init/mpi_barrier/mpi_finalize, all execution times given in seconds, all launch message sizes in bytes):
Per-node scaling, taken at 1ppn:
#nodes original trunk revised trunk
time size time size
1 0.10 819 0.09 564
2 0.14 1070 0.14 677
3 0.15 1321 0.14 790
4 0.15 1572 0.15 903
8 0.17 2576 0.20 1355
16 0.25 4584 0.21 2259
32 0.28 8600 0.27 4067
64 0.50 16632 0.39 7683
Per-proc scaling, taken at 64 nodes
ppn original trunk revised trunk
time size time size
1 0.50 16669 0.40 7720
2 0.55 32733 0.54 11048
3 0.87 48797 0.81 14376
4 1.0 64861 0.85 17704
Condensing those numbers, it appears we gained:
per-node message size: 251 bytes/node -> 113 bytes/node
per-proc message size: 251 bytes/proc -> 52 bytes/proc
per-job message size: 568 bytes/job -> 399 bytes/job
(job-specific data such as jobid, override oversubscribe flag, total #procs in job, total slots allocated)
The fact that the two pre-commit trunk numbers are the same confirms the fact that each proc was containing the node data as well. It isn't quite the 10x message reduction I had hoped to get, but it is significant and gives much better scaling.
Note that the timing info was, as usual, pretty chaotic - the numbers cited here were typical across several runs taken after the initial one to avoid NFS file positioning influences.
Also note that this commit removes the orte_process_info.vpid_start field and the handful of places that passed that useless value. By definition, all jobs start at vpid=0, so all we were doing is passing "0" around. In fact, many places simply hardwired it to "0" anyway rather than deal with it.
This commit was SVN r16428.
The commit has been tested for C/R and Cray operations, and on Odin (SLURM, rsh) and RoadRunner (TM). I tried to update all environments, but obviously could not test them. I know that Windows needs some work, and have highlighted what is know to be needed in the odls process component.
This represents a lot of work by Brian, Tim P, Josh, and myself, with much advice from Jeff and others. For posterity, I have appended a copy of the email describing the work that was done:
As we have repeatedly noted, the modex operation in MPI_Init is the single greatest consumer of time during startup. To-date, we have executed that operation as an ORTE stage gate that held the process until a startup message containing all required modex (and OOB contact info - see #3 below) info could be sent to it. Each process would send its data to the HNP's registry, which assembled and sent the message when all processes had reported in.
In addition, ORTE had taken responsibility for monitoring process status as it progressed through a series of "stage gates". The process reported its status at each gate, and ORTE would then send a "release" message once all procs had reported in.
The incoming changes revamp these procedures in three ways:
1. eliminating the ORTE stage gate system and cleanly delineating responsibility between the OMPI and ORTE layers for MPI init/finalize. The modex stage gate (STG1) has been replaced by a collective operation in the modex itself that performs an allgather on the required modex info. The allgather is implemented using the orte_grpcomm framework since the BTL's are not active at that point. At the moment, the grpcomm framework only has a "basic" component analogous to OMPI's "basic" coll framework - I would recommend that the MPI team create additional, more advanced components to improve performance of this step.
The other stage gates have been replaced by orte_grpcomm barrier functions. We tried to use MPI barriers instead (since the BTL's are active at that point), but - as we discussed on the telecon - these are not currently true barriers so the job would hang when we fell through while messages were still in process. Note that the grpcomm barrier doesn't actually resolve that problem, but Brian has pointed out that we are unlikely to ever see it violated. Again, you might want to spend a little time on an advanced barrier algorithm as the one in "basic" is very simplistic.
Summarizing this change: ORTE no longer tracks process state nor has direct responsibility for synchronizing jobs. This is now done via collective operations within the MPI layer, albeit using ORTE collective communication services. I -strongly- urge the MPI team to implement advanced collective algorithms to improve the performance of this critical procedure.
2. reducing the volume of data exchanged during modex. Data in the modex consisted of the process name, the name of the node where that process is located (expressed as a string), plus a string representation of all contact info. The nodename was required in order for the modex to determine if the process was local or not - in addition, some people like to have it to print pretty error messages when a connection failed.
The size of this data has been reduced in three ways:
(a) reducing the size of the process name itself. The process name consisted of two 32-bit fields for the jobid and vpid. This is far larger than any current system, or system likely to exist in the near future, can support. Accordingly, the default size of these fields has been reduced to 16-bits, which means you can have 32k procs in each of 32k jobs. Since the daemons must have a vpid, and we require one daemon/node, this also restricts the default configuration to 32k nodes.
To support any future "mega-clusters", a configuration option --enable-jumbo-apps has been added. This option increases the jobid and vpid field sizes to 32-bits. Someday, if necessary, someone can add yet another option to increase them to 64-bits, I suppose.
(b) replacing the string nodename with an integer nodeid. Since we have one daemon/node, the nodeid corresponds to the local daemon's vpid. This replaces an often lengthy string with only 2 (or at most 4) bytes, a substantial reduction.
(c) when the mca param requesting that nodenames be sent to support pretty error messages, a second mca param is now used to request FQDN - otherwise, the domain name is stripped (by default) from the message to save space. If someone wants to combine those into a single param somehow (perhaps with an argument?), they are welcome to do so - I didn't want to alter what people are already using.
While these may seem like small savings, they actually amount to a significant impact when aggregated across the entire modex operation. Since every proc must receive the modex data regardless of the collective used to send it, just reducing the size of the process name removes nearly 400MBytes of communication from a 32k proc job (admittedly, much of this comm may occur in parallel). So it does add up pretty quickly.
3. routing RML messages to reduce connections. The default messaging system remains point-to-point - i.e., each proc opens a socket to every proc it communicates with and sends its messages directly. A new option uses the orteds as routers - i.e., each proc only opens a single socket to its local orted. All messages are sent from the proc to the orted, which forwards the message to the orted on the node where the intended recipient proc is located - that orted then forwards the message to its local proc (the recipient). This greatly reduces the connection storm we have encountered during startup.
It also has the benefit of removing the sharing of every proc's OOB contact with every other proc. The orted routing tables are populated during launch since every orted gets a map of where every proc is being placed. Each proc, therefore, only needs to know the contact info for its local daemon, which is passed in via the environment when the proc is fork/exec'd by the daemon. This alone removes ~50 bytes/process of communication that was in the current STG1 startup message - so for our 32k proc job, this saves us roughly 32k*50 = 1.6MBytes sent to 32k procs = 51GBytes of messaging.
Note that you can use the new routing method by specifying -mca routed tree - if you so desire. This mode will become the default at some point in the future.
There are a few minor additional changes in the commit that I'll just note in passing:
* propagation of command line mca params to the orteds - fixes ticket #1073. See note there for details.
* requiring of "finalize" prior to "exit" for MPI procs - fixes ticket #1144. See note there for details.
* cleanup of some stale header files
This commit was SVN r16364.
* General TCP cleanup for OPAL / ORTE
* Simplifying the OOB by moving much of the logic into the RML
* Allowing the OOB RML component to do routing of messages
* Adding a component framework for handling routing tables
* Moving the xcast functionality from the OOB base to its own framework
Includes merge from tmp/bwb-oob-rml-merge revisions:
r15506, r15507, r15508, r15510, r15511, r15512, r15513
This commit was SVN r15528.
The following SVN revisions from the original message are invalid or
inconsistent and therefore were not cross-referenced:
r15506
r15507
r15508
r15510
r15511
r15512
r15513
