Fix race conditions in abnormal terminations. We had done a first-cut at this in a prior commit. However, the window remained partially open due to the fact that the HNP has multiple paths leading to orte_finalize. Most of our frameworks don't care if they are finalized more than once, but one of them does, which meant we segfaulted if orte_finalize got called more than once. Besides, we really shouldn't be doing that anyway.
So we now introduce a set of atomic locks that prevent us from multiply calling abort, attempting to call orte_finalize, etc. My initial tests indicate this is working cleanly, but since it is a race condition issue, more testing will have to be done before we know for sure that this problem has been licked.
Also, some updates relevant to the tool comm library snuck in here. Since those also touched the orted code (as did the prior changes), I didn't want to attempt to separate them out - besides, they are coming in soon anyway. More on them later as that functionality approaches completion.
This commit was SVN r17843.
methods (in order of precedence):
1. #pragma ident <ident string> (e.g., Intel and Sun)
1. #ident <ident string> (e.g., GCC)
1. static const char ident[] = <ident string> (all others)
By default, the ident string used is the standard Open MPI version string. Only
the following libraries will get the embedded version strings (e.g., DSOs will
not):
* libmpi.so
* libmpi_cxx.so
* libmpi_f77.so
* libopen-pal.so
* libopen-rte.so
* Added two new configure options:
* `--with-package-name="STRING"` (defaults to "Open MPI username@hostname
Distribution"). `STRING` is displayed by `ompi_info` next to the "Package"
heading.
* `--with-ident-string="STRING"` (defaults to the standard Open MPI version
string - e.g., X.Y.Zr######). `%VERSION%` will expand to the Open MPI
version string if it is supplied to this configure option.
This commit was SVN r16644.
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.
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.
The primary change that underlies all this is in the OOB. Specifically, the problem in the code until now has been that the OOB attempts to resolve an address when we call the "send" to an unknown recipient. The OOB would then wait forever if that recipient never actually started (and hence, never reported back its OOB contact info). In the case of an orted that failed to start, we would correctly detect that the orted hadn't started, but then we would attempt to order all orteds (including the one that failed to start) to die. This would cause the OOB to "hang" the system.
Unfortunately, revising how the OOB resolves addresses introduced a number of additional problems. Specifically, and most troublesome, was the fact that comm_spawn involved the immediate transmission of the rendezvous point from parent-to-child after the child was spawned. The current code used the OOB address resolution as a "barrier" - basically, the parent would attempt to send the info to the child, and then "hold" there until the child's contact info had arrived (meaning the child had started) and the send could be completed.
Note that this also caused comm_spawn to "hang" the entire system if the child never started... The app-failed-to-start helped improve that behavior - this code provides additional relief.
With this change, the OOB will return an ADDRESSEE_UNKNOWN error if you attempt to send to a recipient whose contact info isn't already in the OOB's hash tables. To resolve comm_spawn issues, we also now force the cross-sharing of connection info between parent and child jobs during spawn.
Finally, to aid in setting triggers to the right values, we introduce the "arith" API for the GPR. This function allows you to atomically change the value in a registry location (either divide, multiply, add, or subtract) by the provided operand. It is equivalent to first fetching the value using a "get", then modifying it, and then putting the result back into the registry via a "put".
This commit was SVN r14711.
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
yesterday and set it to "true" in orte_init(). But ompi_mpi_init()
doesn't call orte_init() -- it calls orte_init_stage1() and
orte_init_stage2(). So orte_initialized was never set to true, and
Badness happend from there (w.r.t. ompi_mpi_abort()).
This patch moves the setting of orte_initialized to orte_init_stage2()
so that everyone will always get it set properly.
It also moves setting orte_universe_info.state to RUNNING into
stage2() as well -- Ralph confirmed that that should have been there
for the same reasons that orte_initialized needs to be there.
This commit was SVN r13374.
completed successfully, Bad Things(tm) could happen.
* Now we explicitly check orte_initialized (a new global in ORTE
indicating whether we are between orte_init() and orte_finalize()
or not), and if so, react accordingly.
* If ORTE is initialized, use orte_system_info.nodename; otherwise,
use gethostname().
* Add loop protection to ensure that ompi_mpi_abort() is not invoked
multiple times recursively.
This commit was SVN r13354.
1. add a "cancel_operation" API to the pls components that allows orterun to demand that an orted operation (e.g., terminate_job) be immediately cancelled and abandoned.
2. changes the pls orted commands from blocking to non-blocking. This allows us to interrupt those operations should an orted be non-responsive. The change also adds an orte_abort_timeout that limits how long orterun will automatically wait for the orteds to respond - if the terminate command, for example, doesn't see orted response within that time, then we printout an appropriate error message and just give up.
3. modifies orterun to allow multiple ctrl-c's to simply abort the program even if the orteds have not responded
4. does some cleanup on the orte-level mca params so that their implementation looks a lot more like that of ompi - makes it easier to maintain. This change also includes the definition of an orte_abort_timeout struct and associated MCA param (can't have too many!) so you can set the time after which orterun gives up on waiting for orteds to respond
This needs more testing before migrating to 1.2.
This commit was SVN r13304.
- 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.
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.
orte_init_stage1(), since not all ORTE processes call orte_init().
* Expad opal_error test case to make sure ORTE error codes print
properly
* Make project error codes start at easy values (OPAL is -1 to -100,
ORTE is -101 to -200, OMPI is less than -201) to make it easier
to figure out what an error code as an integer means. Also has
the nice property of not changing the values of error codes ever
time a new error code is added.
This commit was SVN r7061.
- Change orte_base_infrastructre to orte_infrastructre to conform with
ompi_info's needs
- Move MCA Param registration in ORTE to a centralized function that is
called first in orte_init_stage1
- Set the infrastructre flag as an argument to orte_init
- Adjust initalization functions to properly pass down the infrastructre
flag.
This commit was SVN r7053.
OPAL_ERROR, same for all the other error codes. Also, make sure that there
are never conflicts between OPAL anr ORTE error codes (for example).
Finally, provide opal_perror(), opal_strerror(), and opal_strerror_r() to
give stringified error messages for the different error codes
This commit was SVN r6969.
