If we cannot resolve the route to the peer that we're trying to send
to, don't queue up the message in the TCP OOB -- instead, return it to
the upper layer (e.g., the RML) and let it decide what to do.
In the case of the routed RML, the tree component will queue it up for
later transmission. Hence, we don't want the message queued up both
here in the TCP OOB and the tree routed. Also see some more
discussion / explanation in #1171.
This commit was SVN r16540.
The following SVN revision numbers were found above:
r16513 --> open-mpi/ompi@7ae9589d70
The following Trac tickets were found above:
Ticket 1170 --> https://svn.open-mpi.org/trac/ompi/ticket/1170
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 The modex stage gate (STG1) has been replaced by a collective operation in the modex itself that performs an allgather on the required modex info.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
Cleanup ALL instances of output involving the printing of orte_process_name_t structures using the ORTE_NAME_ARGS macro so that the number of fields and type of data match. Replace those values with a new macro/function pair ORTE_NAME_PRINT that outputs a string (using the new thread safe data capability) so that any future changes to the printing of those structures can be accomplished with a change to a single point.
Note that I could not possibly find outputs that directly print the orte_process_name_t fields, but only dealt with those that used ORTE_NAME_ARGS. Hence, you may still have a few outputs that bark during compilation. Also, I could only verify those that fall within environments I can compile on, so other environments may yield some minor warnings.
This commit was SVN r15517.
VxWorks. Still some issues remaining, I'm sure.
Refs trac:1010
This commit was SVN r15320.
The following Trac tickets were found above:
Ticket 1010 --> https://svn.open-mpi.org/trac/ompi/ticket/1010
structures in the system. Instead of using memcmp, use the ns function.
This won't cause a problem as long as all three elements of the name are
ints, but if they have different sizes, alignment and padding rules
can cause memcmp() to compare padding space, which rarely holds a sane
value.
This commit was SVN r14998.
* Move ipv6comat.h code into opal_config_bottom.h and change into some
more intelligent testing of structures
* Change opal's if interface to use sockaddr instead of sockaddr_storage,
as the RFCs suggest we do
* Move the networking code in opal that isn't directly related to if
detection into net.h
* Add quicky function to get the port out of either a sockaddr_in
or sockaddr_in6, saving a bunch of code in the oob.
* Update TCP oob and btl with new interface
This commit was SVN r14679.
- make opal_sockaddr2str() take a sockaddr_storage instead of a sockaddr_in6
so that it works for IPv4 and IPv6 addresses, and remove a whole bunch
of #ifs in the OOOB code.
- Fix a compiler warning in the TCP BTL due to run-time determined
array size by making it a dynamicly allocated array.
- Fix the unpacking code of IPv4 addresses when using IPv6 support, so
that the address is in the correct location (instead of in an IPv6
structure, use an IPv4 structure). Refs trac:1005.
This commit was SVN r14514.
The following Trac tickets were found above:
Ticket 1005 --> https://svn.open-mpi.org/trac/ompi/ticket/1005
* Remove the connect() timeout code, as it had some nasty race conditions
when connections were established as the trigger was firing. A better
solution has been found for the cluster where this was needed, so just
removing it was easiest.
* When a fatal error (too many connection failures) occurs, set an error
on messages in the queue even if there isn't an active message. The
first message to any peer will be queued without being active (and
so will all subsequent messages until the connection is established),
and the orteds will hang until that first message completes. So if
an orted can never contact it's peer, it will never exit and just sit
waiting for that message to complete.
* Cover an interesting RST condition in the connect code. A connection
can complete the three-way handshake, the connector can even send
some data, but the server side will drop the connection because it
can't move it from the half-connected to fully-connected state because
of space shortage in the listen backlog queue. This causes a RST to
be received first time that recv() is called, which will be when waiting
for the remote side of the OOB ack. In this case, transition the
connection back into a CLOSED state and try to connect again.
* Add levels of debugging, rather than all or nothing, each building on
the previous level. 0 (default) is hard errors. 1 is connection
error debugging info. 2 is all connection info. 3 is more state
info. 4 includes all message info.
* Add some hopefully useful comments
This commit was SVN r14261.
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
its bigger than the timeout for the connect() call, just don't register
the handler by default and fall back to connect() timing out. Should give
much happier performance on big clusters.
This commit was SVN r13639.
Accordingly, there are new APIs to the name service to support the ability to get a job's parent, root, immediate children, and all its descendants. In addition, the terminate_job, terminate_orted, and signal_job APIs for the PLS have been modified to accept attributes that define the extent of their actions. For example, doing a "terminate_job" with an attribute of ORTE_NS_INCLUDE_DESCENDANTS will terminate the given jobid AND all jobs that descended from it.
I have tested this capability on a MacBook under rsh, Odin under SLURM, and LANL's Flash (bproc). It worked successfully on non-MPI jobs (both simple and including a spawn), and MPI jobs (again, both simple and with a spawn).
This commit was SVN r12597.
We were still waiting the entire duration of the timeout before we figured out that a connect() was successful. Re-introduce adding the peer_send_event so that we detect immediately when a connect() completes.
Also make sure to delete the timeout event in complete_connect().
Fixed a struct timeval initialization warning reported by Jeff.
Remove an erroneous opal_output().
This commit was SVN r11724.
The following SVN revision numbers were found above:
r11718 --> open-mpi/ompi@1b6231a9b5
Each 's' partition has its own TCP network. It's fine to use this network for jobs that fit inside the partition, but the TCP OOB errors when trying to connect across two partitions, because there are two disjoint networks. Each node also has another TCP network connecting ALL nodes together.
So the solution is to actually try all the available TCP interfaces on a node, instead of erroring when the first one fails.
Also, the default TCP connect() timeout is way too long (5 minutes) - use our own timeout mechanism, with the timeout value expressed as an MCA parameter.
This commit was SVN r11718.
- use the OPAL functions for PATH and environment variables
- make all headers C++ friendly
- no unamed structures
- no implicit cast.
Plus a full implementation for the orte_wait functions.
This commit was SVN r11347.
copy of the receive buffer based on the iovec struct that may have been updated
during partial reads to reflect the current offset. Need to make the copy using
the base address of the buffer.
Thanks to Sven Stork for finding this.
This should be backported to 1.0.X and 1.1.X branches.
This commit was SVN r9749.
- 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.
some orted's to stall on locks in the MPI Dynamics cases. Since it
is not essentual that we call these functions, they can so away.
Unlock the peer lock when aborting. This causes a potential deadlock
in do_waitall [see comment in code]. This was causing orteds to
deadlock at times when the seed had terminated. With proper interleaving
and timing the orted was deadlocking. This seems to have fixed this in
my stress testing with MPI 2 Dynamics.
This commit was SVN r7539.
CTRL-C'd.
We were calling orte_finalize recursively which caused a segv when it tried to
use a freed framework (orte_rmgr in this case).
I added a status flag to orte_universe_info to indicate where we are in the code.
This was needed to determine if we should call orte_abort or not when shutting
down in the tcp oob.
This commit was SVN r7160.
