The intercomm "merge" function can create a linkage between procs that was not reflected anywhere in a modex, and so at least some of the procs in the resulting communicator don't know how to talk to some of the new communicator's peers.
For example, consider the case where:
1. parent job A comm_spawns a process (job B) - these processes exchange modex and can communicate
2. parent job A now comm_spawns another process (job C) - again, these can communicate, but the proc in C knows nothing of B
3. do an intercomm merge across the communicators created by the two comm_spawns. This puts B and C into the same communicator, but they know nothing about how to talk to each other as they were not involved in any exchange of contact info. Hence, collectives on that communicator now fail.
This fix adds an API to the ompi/dpm framework that (a) exchanges the modex info across the procs in the merge to ensure all procs know how to communicate, and (b) calls add_procs to give the btl's a chance to select transports to any new procs.
cmr:v1.7.3:reviewer=jsquyres
This commit was SVN r29166.
The following Trac tickets were found above:
Ticket 2904 --> https://svn.open-mpi.org/trac/ompi/ticket/2904
* paccept - establish a persistent listening port for async connect requests
* pconnect - async connect to remote process that has posted a paccept port. Provides a timeout mechanism, and allows the underlying implementation to retry until timeout
* pclose - shuts down a prior paccept posting
Includes example programs paccept.c and pconnect.c in orte/test/mpi. New MPI extension interfaces coming...
This commit was SVN r29063.
*** THIS RFC INCLUDES A MINOR CHANGE TO THE MPI-RTE INTERFACE ***
Note: during the course of this work, it was necessary to completely separate the MPI and RTE progress engines. There were multiple places in the MPI layer where ORTE_WAIT_FOR_COMPLETION was being used. A new OMPI_WAIT_FOR_COMPLETION macro was created (defined in ompi/mca/rte/rte.h) that simply cycles across opal_progress until the provided flag becomes false. Places where the MPI layer blocked waiting for RTE to complete an event have been modified to use this macro.
***************************************************************************************
I am reissuing this RFC because of the time that has passed since its original release. Since its initial release and review, I have debugged it further to ensure it fully supports tests like loop_spawn. It therefore seems ready for merge back to the trunk. Given its prior review, I have set the timeout for one week.
The code is in https://bitbucket.org/rhc/ompi-oob2
WHAT: Rewrite of ORTE OOB
WHY: Support asynchronous progress and a host of other features
WHEN: Wed, August 21
SYNOPSIS:
The current OOB has served us well, but a number of limitations have been identified over the years. Specifically:
* it is only progressed when called via opal_progress, which can lead to hangs or recursive calls into libevent (which is not supported by that code)
* we've had issues when multiple NICs are available as the code doesn't "shift" messages between transports - thus, all nodes had to be available via the same TCP interface.
* the OOB "unloads" incoming opal_buffer_t objects during the transmission, thus preventing use of OBJ_RETAIN in the code when repeatedly sending the same message to multiple recipients
* there is no failover mechanism across NICs - if the selected NIC (or its attached switch) fails, we are forced to abort
* only one transport (i.e., component) can be "active"
The revised OOB resolves these problems:
* async progress is used for all application processes, with the progress thread blocking in the event library
* each available TCP NIC is supported by its own TCP module. The ability to asynchronously progress each module independently is provided, but not enabled by default (a runtime MCA parameter turns it "on")
* multi-address TCP NICs (e.g., a NIC with both an IPv4 and IPv6 address, or with virtual interfaces) are supported - reachability is determined by comparing the contact info for a peer against all addresses within the range covered by the address/mask pairs for the NIC.
* a message that arrives on one TCP NIC is automatically shifted to whatever NIC that is connected to the next "hop" if that peer cannot be reached by the incoming NIC. If no TCP module will reach the peer, then the OOB attempts to send the message via all other available components - if none can reach the peer, then an "error" is reported back to the RML, which then calls the errmgr for instructions.
* opal_buffer_t now conforms to standard object rules re OBJ_RETAIN as we no longer "unload" the incoming object
* NIC failure is reported to the TCP component, which then tries to resend the message across any other available TCP NIC. If that doesn't work, then the message is given back to the OOB base to try using other components. If all that fails, then the error is reported to the RML, which reports to the errmgr for instructions
* obviously from the above, multiple OOB components (e.g., TCP and UD) can be active in parallel
* the matching code has been moved to the RML (and out of the OOB/TCP component) so it is independent of transport
* routing is done by the individual OOB modules (as opposed to the RML). Thus, both routed and non-routed transports can simultaneously be active
* all blocking send/recv APIs have been removed. Everything operates asynchronously.
KNOWN LIMITATIONS:
* although provision is made for component failover as described above, the code for doing so has not been fully implemented yet. At the moment, if all connections for a given peer fail, the errmgr is notified of a "lost connection", which by default results in termination of the job if it was a lifeline
* the IPv6 code is present and compiles, but is not complete. Since the current IPv6 support in the OOB doesn't work anyway, I don't consider this a blocker
* routing is performed at the individual module level, yet the active routed component is selected on a global basis. We probably should update that to reflect that different transports may need/choose to route in different ways
* obviously, not every error path has been tested nor necessarily covered
* determining abnormal termination is more challenging than in the old code as we now potentially have multiple ways of connecting to a process. Ideally, we would declare "connection failed" when *all* transports can no longer reach the process, but that requires some additional (possibly complex) code. For now, the code replicates the old behavior only somewhat modified - i.e., if a module sees its connection fail, it checks to see if it is a lifeline. If so, it notifies the errmgr that the lifeline is lost - otherwise, it notifies the errmgr that a non-lifeline connection was lost.
* reachability is determined solely on the basis of a shared subnet address/mask - more sophisticated algorithms (e.g., the one used in the tcp btl) are required to handle routing via gateways
* the RML needs to assign sequence numbers to each message on a per-peer basis. The receiving RML will then deliver messages in order, thus preventing out-of-order messaging in the case where messages travel across different transports or a message needs to be redirected/resent due to failure of a NIC
This commit was SVN r29058.
Notes:
- This commit also eliminates the need for an available components list in use
in several frameworks. None of the code in question was making use of the
priority field of the priority component list item so these extra lists were
removed.
- Cleaned up selection code in several frameworks to sort lists using opal_list_sort.
- Cleans up the ompi/orte-info functions. Expose the functions that construct the
list of params so they can be used elsewhere.
patches for mtl/portals4 from brian
missed a few output variables in openib
This commit was SVN r28241.
Roll in the ORTE state machine. Remove last traces of opal_sos. Remove UTK epoch code.
Please see the various emails about the state machine change for details. I'll send something out later with more info on the new arch.
This commit was SVN r26242.
Turns out, this isn't necessarily true. The Cray, for example, launches processes in a toroidal pattern, thus causing the daemons to wind up somewhere other than what we thought. Other environments (e.g., slurm) are also capable of such behavior, depending upon the default mapping algorithm they are told to use.
Resolve this problem by making the daemon-to-node assignment in the affected environments when the daemon calls back and tells us what node it is on. Order the nodes in the mapping list so they are in daemon-vpid order as opposed to the order in which they show in the allocation. For environments that don't exhibit this mapping behavior (e.g., rsh), this won't have any impact.
Also, clean up the vm launch procedure a little bit so it more closely aligns with the state machine implementation that is coming, and remove some lingering "slave" code.
This commit was SVN r25551.
https://svn.open-mpi.org/trac/ompi/wiki/ProcessPlacement
The wiki page is incomplete at the moment, but I hope to complete it over the next few days. I will provide updates on the devel list. As the wiki page states, the default and most commonly used options remain unchanged (except as noted below). New, esoteric and complex options have been added, but unless you are a true masochist, you are unlikely to use many of them beyond perhaps an initial curiosity-motivated experimentation.
In a nutshell, this commit revamps the map/rank/bind procedure to take into account topology info on the compute nodes. I have, for the most part, preserved the default behaviors, with three notable exceptions:
1. I have at long last bowed my head in submission to the system admin's of managed clusters. For years, they have complained about our default of allowing users to oversubscribe nodes - i.e., to run more processes on a node than allocated slots. Accordingly, I have modified the default behavior: if you are running off of hostfile/dash-host allocated nodes, then the default is to allow oversubscription. If you are running off of RM-allocated nodes, then the default is to NOT allow oversubscription. Flags to override these behaviors are provided, so this only affects the default behavior.
2. both cpus/rank and stride have been removed. The latter was demanded by those who didn't understand the purpose behind it - and I agreed as the users who requested it are no longer using it. The former was removed temporarily pending implementation.
3. vm launch is now the sole method for starting OMPI. It was just too darned hard to maintain multiple launch procedures - maybe someday, provided someone can demonstrate a reason to do so.
As Jeff stated, it is impossible to fully test a change of this size. I have tested it on Linux and Mac, covering all the default and simple options, singletons, and comm_spawn. That said, I'm sure others will find problems, so I'll be watching MTT results until this stabilizes.
This commit was SVN r25476.
To enable the epochs and the resilient orte code, use the configure flag:
--enable-resilient-orte
This will define both:
ORTE_ENABLE_EPOCH
ORTE_RESIL_ORTE
This commit was SVN r25093.
Apparently, gcc 4.4.x and 4.5.x complain about the ''possibility'' of
us calling free() on a non-heap variable. We know that this case can
never happen because the refcount will absolutely not go to zero
here. We think it may be gcc being a bit too aggressive on the
warnings.
However, since this happens with gcc 4.4.x and 4.5.x, and since gcc
4.5.x ship in RHEL6 and Fedora 14 (and others), someone '''will'''
complain about this in the future, so we might as well code around it
so that we don't have to keep explaining "despite the warning, it's
really ok."
The workaround is pretty simple: just OBJ_RELEASE the values from
ompi_mpi_comm_parent before it is re-assigned to the new
intercommunicator. Then the compiler's static code analysis can't
possibly tell that it's not a heap variable, and we're ok.
So yes, we are still calling OBJ_RELEASE on a non-heap variable. But
free() '''will never be called''' on it because of the refcount.
This commit was SVN r24214.
The following Trac tickets were found above:
Ticket 2669 --> https://svn.open-mpi.org/trac/ompi/ticket/2669
Create an ability to store the contact info for multiple HNPs being used to route between different job families. Modify the dpm orte module to pass the resulting store during the connect_accept procedure so that all jobs involved in the resulting communicator know how to route OOB messages between them.
Add a test provided by Philippe that tests this ability.
This commit was SVN r23438.
(OMPI_ERR_* = OPAL_SOS_GET_ERR_CODE(ret)), since the return value could be a
SOS-encoded error. The OPAL_SOS_GET_ERR_CODE() takes in a SOS error and returns
back the native error code.
* Since OPAL_SUCCESS is preserved by SOS, also change all calls of the form
(OPAL_ERROR == ret) to (OPAL_SUCCESS != ret). We thus avoid having to
decode 'ret' to get the native error code.
This commit was SVN r23162.
Add a ''map_bynode'' info key to determine if the job to be started by comm_spawn* should be mapped by node or by slot. Default is to map according to the default policy set when the parent job was started.
cmr:v1.5.1
This commit was SVN r22564.
in the v1.2 series the cid's could never go above the max. allowed for a
particular pml. Because of that, pml_add_comm never checked for the cid, and
in fact pml_add_comm was called in comm_set, which is *before* we knew the
cid.
in the v1.3 series (and trunk) we check now the cid to detect overflow, and
because of that pml_add_comm has been moved *after* the cid allocation
routine, namely into the comm_activate routine.
in the v1.2 series, the comm_activate contained a synchronization step of the
old communicator in order to prevent incoming fragments on the new
communicator, with the main problem being that the allreduce in the
communicator allocation finished at different times on different processes,
and thus, this scenario could and did really occur.
in the v1.3 series, the comm_activate does not contain the synchronization
step anymore, since we introduced the new queue for fragments with unknown
cid. The problem is however, that whether a fragment is known or not is
decided by using ompi_comm_lookup(), which will return something useful as
soon as the cid allocation finished, even before pml_add_comm has been
called. So there is a small time gap where we will not post a message into
queue for unknown cid's, but we can also not look up the process structure
belonging to the rank in that comm ( that is in pml_ob1_match_recv_frag or
something like that).
The current fix reintroduces the synchronization step in comm_activate, and
ensures that no fragment can be received for a new communicator before the
synchronization occurs , and thus comm_nextcid() and pml_add_comm has been
called. It seems to be the safest and easiest way for now. Welcome back, v1.2.
This commit was SVN r21970.
happens when hierarch is used. . Two major items:
- modify the comm_activate step to take an additional argument, indicating
whether the new communicatio has to go through the collective selection
step. This is not required sometimes (e.g. when a process calls
MPI_COMM_SPLIT with color=MPI_UNDEFINED), and contributed significantly to
the exhaustion of cids.
- when freeing a communicator, check whether we can reuse the block of cids
assigned to that comm. This only works if the current front of the cid
assignment (cid_block_start) is right ater the block of cids assigned to this
comm.
Fixes trac:1904
Fixes trac:1926
This commit was SVN r21296.
The following Trac tickets were found above:
Ticket 1904 --> https://svn.open-mpi.org/trac/ompi/ticket/1904
Ticket 1926 --> https://svn.open-mpi.org/trac/ompi/ticket/1926
OMPI_* to OPAL_*. This allows opal layer to be used more independent
from the whole of ompi.
NOTE: 9 "svn mv" operations immediately follow this commit.
This commit was SVN r21180.
- 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.
We currently apply all of the MCA params in the parent job to the child. This commit allows a user to specify additional params for the child job, and to override any pre-existing params with the new value so they can better control behavior of the child job.
This commit was SVN r20989.
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.
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.
Fix a mistake in the dpm that hardcoded the update of routes to the HNP. This needs to be done by the individual routing modules so they can take whatever action is required - which will usually include updating the HNP, but might not...and might include additional steps. New routing modules are coming that violated this assumption, so it had to be moved back into init_routes.
All current routed modules know what to do - anyone with routed modules not in the current trunk may need to adjust them (see any of the current routed modules for examples of what to do).
This commit was SVN r20427.
I'm unable to split it in two parts, my patch and Edgar's one. So I just update
copyright information for both of us.
What this patch do:
- it use the unexpected queue create by commit r19562 to dispatch the
unexpected message to the right communicator (once this communicator
is created and initialized).
- delay the PML comm_add until we have the context_id for the new communicator.
- only do the PML comm_add on processes that really belong to the new
communicator. Please read the lengthy comment in the source code for the
reason behind this.
This commit was SVN r19929.
The following SVN revision numbers were found above:
r19562 --> open-mpi/ompi@acd3406aa7
1. completely and cleanly separates responsibilities between the HNP, orted, and tool components.
2. removes all wireup messaging during launch and shutdown.
3. maintains flow control for stdin to avoid large-scale consumption of memory by orteds when large input files are forwarded. This is done using an xon/xoff protocol.
4. enables specification of stdin recipients on the mpirun cmd line. Allowed options include rank, "all", or "none". Default is rank 0.
5. creates a new MPI_Info key "ompi_stdin_target" that supports the above options for child jobs. Default is "none".
6. adds a new tool "orte-iof" that can connect to a running mpirun and display the output. Cmd line options allow selection of any combination of stdout, stderr, and stddiag. Default is stdout.
7. adds a new mpirun and orte-iof cmd line option "tag-output" that will tag each line of output with process name and stream ident. For example, "[1,0]<stdout>this is output"
This is not intended for the 1.3 release as it is a major change requiring considerable soak time.
This commit was SVN r19767.
