(C) 2010 by Argonne National Laboratory.

    See COPYRIGHT in top-level directory.

Automatically generated

  by:   ./maint/extractcvars

  at:   Fri Nov 10 20:21:16 2017

DO NOT EDIT!!!

This file lists the various environment variables available to change the

behavior of the MPICH library.  These are intended to be used by advanced

users.

---------------------------------------------------------------------------

MPIR_CVAR_DEBUG_HOLD

    Aliases: MPIR_PARAM_DEBUG_HOLD

             MPICH_DEBUG_HOLD

    Description: If true, causes processes to wait in MPI_Init and

        MPI_Initthread for a debugger to be attached.  Once the debugger

        has attached, the variable 'hold' should be set to 0 in order to

        allow the process to continue (e.g., in gdb, "set hold=0").

    Default: 0

MPIR_CVAR_ERROR_CHECKING

    Aliases: MPIR_PARAM_ERROR_CHECKING

             MPICH_ERROR_CHECKING

    Description: If true, perform checks for errors, typically to verify

        valid inputs to MPI routines.  Only effective when MPICH is

        configured with --enable-error-checking=runtime .

    Default: 1

MPIR_CVAR_ASYNC_PROGRESS

    Aliases: MPIR_PARAM_ASYNC_PROGRESS

             MPICH_ASYNC_PROGRESS

    Description: If set to true, MPICH will initiate an additional thread

        to make asynchronous progress on all communication operations

        including point-to-point, collective, one-sided operations and I/O.

         Setting this variable will automatically increase the

        thread-safety level to MPI_THREAD_MULTIPLE.  While this improves

        the progress semantics, it might cause a small amount of

        performance overhead for regular MPI operations.  The user is

        encouraged to leave one or more hardware threads vacant in order to

        prevent contention between the application threads and the progress

        thread(s).  The impact of oversubscription is highly system

        dependent but may be substantial in some cases, hence this

        recommendation.

    Default: 0

MPIR_CVAR_DEFAULT_THREAD_LEVEL

    Aliases: MPIR_PARAM_DEFAULT_THREAD_LEVEL

             MPICH_DEFAULT_THREAD_LEVEL

    Description: Sets the default thread level to use when using MPI_INIT.

        This variable is case-insensitive.

    Default: "MPI_THREAD_SINGLE"

MPIR_CVAR_MEMDUMP

    Aliases: MPIR_PARAM_MEMDUMP

             MPICH_MEMDUMP

    Description: If true, list any memory that was allocated by MPICH and

        that remains allocated when MPI_Finalize completes.

    Default: 1

MPIR_CVAR_SUPPRESS_ABORT_MESSAGE

    Aliases: MPIR_PARAM_SUPPRESS_ABORT_MESSAGE

             MPICH_SUPPRESS_ABORT_MESSAGE

    Description: Disable printing of abort error message.

    Default: 0

MPIR_CVAR_REDUCE_SHORT_MSG_SIZE

    Aliases: MPIR_PARAM_REDUCE_SHORT_MSG_SIZE

             MPICH_REDUCE_SHORT_MSG_SIZE

    Description: the short message algorithm will be used if the send

        buffer size is <= this value (in bytes)

    Default: 2048

MPIR_CVAR_ENABLE_SMP_REDUCE

    Aliases: MPIR_PARAM_ENABLE_SMP_REDUCE

             MPICH_ENABLE_SMP_REDUCE

    Description: Enable SMP aware reduce.

    Default: 1

MPIR_CVAR_MAX_SMP_REDUCE_MSG_SIZE

    Aliases: MPIR_PARAM_MAX_SMP_REDUCE_MSG_SIZE

             MPICH_MAX_SMP_REDUCE_MSG_SIZE

    Description: Maximum message size for which SMP-aware reduce is used. 

        A value of '0' uses SMP-aware reduce for all message sizes.

    Default: 0

MPIR_CVAR_REDSCAT_COMMUTATIVE_LONG_MSG_SIZE

    Aliases: MPIR_PARAM_REDSCAT_COMMUTATIVE_LONG_MSG_SIZE

             MPICH_REDSCAT_COMMUTATIVE_LONG_MSG_SIZE

    Description: the long message algorithm will be used if the operation

        is commutative and the send buffer size is >= this value (in bytes)

    Default: 524288

MPIR_CVAR_BCAST_MIN_PROCS

    Aliases: MPIR_PARAM_BCAST_MIN_PROCS

             MPICH_BCAST_MIN_PROCS

    Description: Let's define short messages as messages with size <

        MPIR_CVAR_BCAST_SHORT_MSG_SIZE, and medium messages as messages

        with size >= MPIR_CVAR_BCAST_SHORT_MSG_SIZE but <

        MPIR_CVAR_BCAST_LONG_MSG_SIZE, and long messages as messages with

        size >= MPIR_CVAR_BCAST_LONG_MSG_SIZE. The broadcast algorithms

        selection procedure is as follows. For short messages or when the

        number of processes is < MPIR_CVAR_BCAST_MIN_PROCS, we do broadcast

        using the binomial tree algorithm. Otherwise, for medium messages

        and with a power-of-two number of processes, we do broadcast based

        on a scatter followed by a recursive doubling allgather algorithm.

        Otherwise, for long messages or with non power-of-two number of

        processes, we do broadcast based on a scatter followed by a ring

        allgather algorithm. (See also: MPIR_CVAR_BCAST_SHORT_MSG_SIZE,

        MPIR_CVAR_BCAST_LONG_MSG_SIZE)

    Default: 8

MPIR_CVAR_BCAST_SHORT_MSG_SIZE

    Aliases: MPIR_PARAM_BCAST_SHORT_MSG_SIZE

             MPICH_BCAST_SHORT_MSG_SIZE

    Description: Let's define short messages as messages with size <

        MPIR_CVAR_BCAST_SHORT_MSG_SIZE, and medium messages as messages

        with size >= MPIR_CVAR_BCAST_SHORT_MSG_SIZE but <

        MPIR_CVAR_BCAST_LONG_MSG_SIZE, and long messages as messages with

        size >= MPIR_CVAR_BCAST_LONG_MSG_SIZE. The broadcast algorithms

        selection procedure is as follows. For short messages or when the

        number of processes is < MPIR_CVAR_BCAST_MIN_PROCS, we do broadcast

        using the binomial tree algorithm. Otherwise, for medium messages

        and with a power-of-two number of processes, we do broadcast based

        on a scatter followed by a recursive doubling allgather algorithm.

        Otherwise, for long messages or with non power-of-two number of

        processes, we do broadcast based on a scatter followed by a ring

        allgather algorithm. (See also: MPIR_CVAR_BCAST_MIN_PROCS,

        MPIR_CVAR_BCAST_LONG_MSG_SIZE)

    Default: 12288

MPIR_CVAR_BCAST_LONG_MSG_SIZE

    Aliases: MPIR_PARAM_BCAST_LONG_MSG_SIZE

             MPICH_BCAST_LONG_MSG_SIZE

    Description: Let's define short messages as messages with size <

        MPIR_CVAR_BCAST_SHORT_MSG_SIZE, and medium messages as messages

        with size >= MPIR_CVAR_BCAST_SHORT_MSG_SIZE but <

        MPIR_CVAR_BCAST_LONG_MSG_SIZE, and long messages as messages with

        size >= MPIR_CVAR_BCAST_LONG_MSG_SIZE. The broadcast algorithms

        selection procedure is as follows. For short messages or when the

        number of processes is < MPIR_CVAR_BCAST_MIN_PROCS, we do broadcast

        using the binomial tree algorithm. Otherwise, for medium messages

        and with a power-of-two number of processes, we do broadcast based

        on a scatter followed by a recursive doubling allgather algorithm.

        Otherwise, for long messages or with non power-of-two number of

        processes, we do broadcast based on a scatter followed by a ring

        allgather algorithm. (See also: MPIR_CVAR_BCAST_MIN_PROCS,

        MPIR_CVAR_BCAST_SHORT_MSG_SIZE)

    Default: 524288

MPIR_CVAR_ENABLE_SMP_BCAST

    Aliases: MPIR_PARAM_ENABLE_SMP_BCAST

             MPICH_ENABLE_SMP_BCAST

    Description: Enable SMP aware broadcast (See also:

        MPIR_CVAR_MAX_SMP_BCAST_MSG_SIZE)

    Default: 1

MPIR_CVAR_MAX_SMP_BCAST_MSG_SIZE

    Aliases: MPIR_PARAM_MAX_SMP_BCAST_MSG_SIZE

             MPICH_MAX_SMP_BCAST_MSG_SIZE

    Description: Maximum message size for which SMP-aware broadcast is

        used.  A value of '0' uses SMP-aware broadcast for all message

        sizes. (See also: MPIR_CVAR_ENABLE_SMP_BCAST)

    Default: 0

MPIR_CVAR_GATHERV_INTER_SSEND_MIN_PROCS

    Aliases: MPIR_PARAM_GATHERV_INTER_SSEND_MIN_PROCS

             MPICH_GATHERV_INTER_SSEND_MIN_PROCS

    Description: Use Ssend (synchronous send) for intercommunicator

        MPI_Gatherv if the "group B" size is >= this value.  Specifying

        "-1" always avoids using Ssend.  For backwards compatibility,

        specifying "0" uses the default value.

    Default: 32

MPIR_CVAR_ALLREDUCE_SHORT_MSG_SIZE

    Aliases: MPIR_PARAM_ALLREDUCE_SHORT_MSG_SIZE

             MPICH_ALLREDUCE_SHORT_MSG_SIZE

    Description: the short message algorithm will be used if the send

        buffer size is <= this value (in bytes)

    Default: 2048

MPIR_CVAR_ENABLE_SMP_COLLECTIVES

    Aliases: MPIR_PARAM_ENABLE_SMP_COLLECTIVES

             MPICH_ENABLE_SMP_COLLECTIVES

    Description: Enable SMP aware collective communication.

    Default: 1

MPIR_CVAR_ENABLE_SMP_ALLREDUCE

    Aliases: MPIR_PARAM_ENABLE_SMP_ALLREDUCE

             MPICH_ENABLE_SMP_ALLREDUCE

    Description: Enable SMP aware allreduce.

    Default: 1

MPIR_CVAR_MAX_SMP_ALLREDUCE_MSG_SIZE

    Aliases: MPIR_PARAM_MAX_SMP_ALLREDUCE_MSG_SIZE

             MPICH_MAX_SMP_ALLREDUCE_MSG_SIZE

    Description: Maximum message size for which SMP-aware allreduce is

        used.  A value of '0' uses SMP-aware allreduce for all message

        sizes.

    Default: 0

MPIR_CVAR_GATHER_VSMALL_MSG_SIZE

    Aliases: MPIR_PARAM_GATHER_VSMALL_MSG_SIZE

             MPICH_GATHER_VSMALL_MSG_SIZE

    Description: use a temporary buffer for intracommunicator MPI_Gather if

        the send buffer size is < this value (in bytes) (See also:

        MPIR_CVAR_GATHER_INTER_SHORT_MSG_SIZE)

    Default: 1024

MPIR_CVAR_GATHER_INTER_SHORT_MSG_SIZE

    Aliases: MPIR_PARAM_GATHER_INTER_SHORT_MSG_SIZE

             MPICH_GATHER_INTER_SHORT_MSG_SIZE

    Description: use the short message algorithm for intercommunicator

        MPI_Gather if the send buffer size is < this value (in bytes) (See

        also: MPIR_CVAR_GATHER_VSMALL_MSG_SIZE)

    Default: 2048

MPIR_CVAR_ENABLE_SMP_BARRIER

    Aliases: MPIR_PARAM_ENABLE_SMP_BARRIER

             MPICH_ENABLE_SMP_BARRIER

    Description: Enable SMP aware barrier.

    Default: 1

MPIR_CVAR_ALLGATHER_SHORT_MSG_SIZE

    Aliases: MPIR_PARAM_ALLGATHER_SHORT_MSG_SIZE

             MPICH_ALLGATHER_SHORT_MSG_SIZE

    Description: For MPI_Allgather and MPI_Allgatherv, the short message

        algorithm will be used if the send buffer size is < this value (in

        bytes). (See also: MPIR_CVAR_ALLGATHER_LONG_MSG_SIZE)

    Default: 81920

MPIR_CVAR_ALLGATHER_LONG_MSG_SIZE

    Aliases: MPIR_PARAM_ALLGATHER_LONG_MSG_SIZE

             MPICH_ALLGATHER_LONG_MSG_SIZE

    Description: For MPI_Allgather and MPI_Allgatherv, the long message

        algorithm will be used if the send buffer size is >= this value (in

        bytes) (See also: MPIR_CVAR_ALLGATHER_SHORT_MSG_SIZE)

    Default: 524288

MPIR_CVAR_ALLTOALL_SHORT_MSG_SIZE

    Aliases: MPIR_PARAM_ALLTOALL_SHORT_MSG_SIZE

             MPICH_ALLTOALL_SHORT_MSG_SIZE

    Description: the short message algorithm will be used if the

        per-destination message size (sendcount*size(sendtype)) is <= this

        value (See also: MPIR_CVAR_ALLTOALL_MEDIUM_MSG_SIZE)

    Default: 256

MPIR_CVAR_ALLTOALL_MEDIUM_MSG_SIZE

    Aliases: MPIR_PARAM_ALLTOALL_MEDIUM_MSG_SIZE

             MPICH_ALLTOALL_MEDIUM_MSG_SIZE

    Description: the medium message algorithm will be used if the

        per-destination message size (sendcount*size(sendtype)) is <= this

        value and larger than MPIR_CVAR_ALLTOALL_SHORT_MSG_SIZE (See also:

        MPIR_CVAR_ALLTOALL_SHORT_MSG_SIZE)

    Default: 32768

MPIR_CVAR_ALLTOALL_THROTTLE

    Aliases: MPIR_PARAM_ALLTOALL_THROTTLE

             MPICH_ALLTOALL_THROTTLE

    Description: max no. of irecvs/isends posted at a time in some alltoall

        algorithms. Setting it to 0 causes all irecvs/isends to be posted

        at once

    Default: 32

MPIR_CVAR_SCATTER_INTER_SHORT_MSG_SIZE

    Aliases: MPIR_PARAM_SCATTER_INTER_SHORT_MSG_SIZE

             MPICH_SCATTER_INTER_SHORT_MSG_SIZE

    Description: use the short message algorithm for intercommunicator

        MPI_Scatter if the send buffer size is < this value (in bytes)

    Default: 2048

MPIR_CVAR_ALLGATHERV_PIPELINE_MSG_SIZE

    Aliases: MPIR_PARAM_ALLGATHERV_PIPELINE_MSG_SIZE

             MPICH_ALLGATHERV_PIPELINE_MSG_SIZE

    Description: The smallest message size that will be used for the

        pipelined, large-message, ring algorithm in the MPI_Allgatherv

        implementation.

    Default: 32768

MPIR_CVAR_CTXID_EAGER_SIZE

    Aliases: MPIR_PARAM_CTXID_EAGER_SIZE

             MPICH_CTXID_EAGER_SIZE

    Description: The MPIR_CVAR_CTXID_EAGER_SIZE environment variable allows

        you to specify how many words in the context ID mask will be set

        aside for the eager allocation protocol.  If the application is

        running out of context IDs, reducing this value may help.

    Default: 2

MPIR_CVAR_COMM_SPLIT_USE_QSORT

    Aliases: MPIR_PARAM_COMM_SPLIT_USE_QSORT

             MPICH_COMM_SPLIT_USE_QSORT

    Description: Use qsort(3) in the implementation of MPI_Comm_split

        instead of bubble sort.

    Default: 1

MPIR_CVAR_PROCTABLE_SIZE

    Aliases: MPIR_PARAM_PROCTABLE_SIZE

             MPICH_PROCTABLE_SIZE

    Description: Size of the "MPIR" debugger interface proctable (process

        table).

    Default: 64

MPIR_CVAR_PROCTABLE_PRINT

    Aliases: MPIR_PARAM_PROCTABLE_PRINT

             MPICH_PROCTABLE_PRINT

    Description: If true, dump the proctable entries at

        MPIR_WaitForDebugger-time.

    Default: 0

MPIR_CVAR_PRINT_ERROR_STACK

    Aliases: MPIR_PARAM_PRINT_ERROR_STACK

             MPICH_PRINT_ERROR_STACK

    Description: If true, print an error stack trace at error handling

        time.

    Default: 1

MPIR_CVAR_CHOP_ERROR_STACK

    Aliases: MPIR_PARAM_CHOP_ERROR_STACK

             MPICH_CHOP_ERROR_STACK

    Description: If >0, truncate error stack output lines this many

        characters wide.  If 0, do not truncate, and if <0 use a sensible

        default.

    Default: 0

MPIR_CVAR_NAMESERV_FILE_PUBDIR

    Aliases: MPIR_PARAM_NAMESERV_FILE_PUBDIR

             MPICH_NAMESERV_FILE_PUBDIR

             MPIR_CVAR_NAMEPUB_DIR

             MPIR_PARAM_NAMEPUB_DIR

             MPICH_NAMEPUB_DIR

    Description: Sets the directory to use for MPI service publishing in

        the file nameserv implementation.  Allows the user to override

        where the publish and lookup information is placed for

        connect/accept based applications.

    Default: NULL

MPIR_CVAR_ABORT_ON_LEAKED_HANDLES

    Aliases: MPIR_PARAM_ABORT_ON_LEAKED_HANDLES

             MPICH_ABORT_ON_LEAKED_HANDLES

    Description: If true, MPI will call MPI_Abort at MPI_Finalize if any

        MPI object handles have been leaked.  For example, if MPI_Comm_dup

        is called without calling a corresponding MPI_Comm_free.  For

        uninteresting reasons, enabling this option may prevent all known

        object leaks from being reported.  MPICH must have been configure

        with "--enable-g=handlealloc" or better in order for this

        functionality to work.

    Default: 0

MPIR_CVAR_COLL_ALIAS_CHECK

    Aliases: MPIR_PARAM_COLL_ALIAS_CHECK

             MPICH_COLL_ALIAS_CHECK

    Description: Enable checking of aliasing in collective operations

    Default: 1

MPIR_CVAR_CH3_ENABLE_HCOLL

    Aliases: MPIR_PARAM_CH3_ENABLE_HCOLL

             MPICH_CH3_ENABLE_HCOLL

    Description: If true, enable HCOLL collectives.

    Default: 0

MPIR_CVAR_CH3_NOLOCAL

    Aliases: MPIR_PARAM_CH3_NOLOCAL

             MPICH_CH3_NOLOCAL

             MPIR_CVAR_CH3_NO_LOCAL

             MPIR_PARAM_CH3_NO_LOCAL

             MPICH_CH3_NO_LOCAL

    Description: If true, force all processes to operate as though all

        processes are located on another node.  For example, this disables

        shared memory communication hierarchical collectives.

    Default: 0

MPIR_CVAR_CH3_ODD_EVEN_CLIQUES

    Aliases: MPIR_PARAM_CH3_ODD_EVEN_CLIQUES

             MPICH_CH3_ODD_EVEN_CLIQUES

             MPIR_CVAR_CH3_EVEN_ODD_CLIQUES

             MPIR_PARAM_CH3_EVEN_ODD_CLIQUES

             MPICH_CH3_EVEN_ODD_CLIQUES

    Description: If true, odd procs on a node are seen as local to each

        other, and even procs on a node are seen as local to each other. 

        Used for debugging on a single machine.

    Default: 0

MPIR_CVAR_CH3_EAGER_MAX_MSG_SIZE

    Aliases: MPIR_PARAM_CH3_EAGER_MAX_MSG_SIZE

             MPICH_CH3_EAGER_MAX_MSG_SIZE

    Description: This cvar controls the message size at which CH3 switches

        from eager to rendezvous mode.

    Default: 131072

MPIR_CVAR_CH3_RMA_SLOTS_SIZE

    Aliases: MPIR_PARAM_CH3_RMA_SLOTS_SIZE

             MPICH_CH3_RMA_SLOTS_SIZE

    Description: Number of RMA slots during window creation. Each slot

        contains a linked list of target elements. The distribution of

        ranks among slots follows a round-robin pattern. Requires a

        positive value.

    Default: 262144

MPIR_CVAR_CH3_RMA_TARGET_LOCK_DATA_BYTES

    Aliases: MPIR_PARAM_CH3_RMA_TARGET_LOCK_DATA_BYTES

             MPICH_CH3_RMA_TARGET_LOCK_DATA_BYTES

    Description: Size (in bytes) of available lock data this window can

        provided. If current buffered lock data is more than this value,

        the process will drop the upcoming operation data. Requires a

        positive calue.

    Default: 655360

MPIR_CVAR_CH3_RMA_OP_PIGGYBACK_LOCK_DATA_SIZE

    Aliases: MPIR_PARAM_CH3_RMA_OP_PIGGYBACK_LOCK_DATA_SIZE

             MPICH_CH3_RMA_OP_PIGGYBACK_LOCK_DATA_SIZE

    Description: Specify the threshold of data size of a RMA operation

        which can be piggybacked with a LOCK message. It is always a

        positive value and should not be smaller than

        MPIDI_RMA_IMMED_BYTES. If user sets it as a small value, for middle

        and large data size, we will lose performance because of always

        waiting for round-trip of LOCK synchronization; if user sets it as

        a large value, we need to consume more memory on target side to

        buffer this lock request when lock is not satisfied.

    Default: 65536

MPIR_CVAR_CH3_RMA_SCALABLE_FENCE_PROCESS_NUM

    Aliases: MPIR_PARAM_CH3_RMA_SCALABLE_FENCE_PROCESS_NUM

             MPICH_CH3_RMA_SCALABLE_FENCE_PROCESS_NUM

    Description: Specify the threshold of switching the algorithm used in

        FENCE from the basic algorithm to the scalable algorithm. The value

        can be nagative, zero or positive. When the number of processes is

        larger than or equal to this value, FENCE will use a scalable

        algorithm which do not use O(P) data structure; when the number of

        processes is smaller than the value, FENCE will use a basic but

        fast algorithm which requires an O(P) data structure.

    Default: 1024

MPIR_CVAR_CH3_RMA_DELAY_ISSUING_FOR_PIGGYBACKING

    Aliases: MPIR_PARAM_CH3_RMA_DELAY_ISSUING_FOR_PIGGYBACKING

             MPICH_CH3_RMA_DELAY_ISSUING_FOR_PIGGYBACKING

    Description: Specify if delay issuing of RMA operations for

        piggybacking LOCK/UNLOCK/FLUSH is enabled. It can be either 0 or 1.

        When it is set to 1, the issuing of LOCK message is delayed until

        origin process see the first RMA operation and piggyback LOCK with

        that operation, and the origin process always keeps the current

        last operation until the ending synchronization call in order to

        piggyback UNLOCK/FLUSH with that operation. When it is set to 0, in

        WIN_LOCK/UNLOCK case, the LOCK message is sent out as early as

        possible, in WIN_LOCK_ALL/UNLOCK_ALL case, the origin process still

        tries to piggyback LOCK message with the first operation; for

        UNLOCK/FLUSH message, the origin process no longer keeps the

        current last operation but only piggyback UNLOCK/FLUSH if there is

        an operation avaliable in the ending synchronization call.

    Default: 0

MPIR_CVAR_CH3_RMA_ACTIVE_REQ_THRESHOLD

    Aliases: MPIR_PARAM_CH3_RMA_ACTIVE_REQ_THRESHOLD

             MPICH_CH3_RMA_ACTIVE_REQ_THRESHOLD

    Description: Threshold of number of active requests to trigger blocking

        waiting in operation routines. When the value is negative, we never

        blockingly wait in operation routines. When the value is zero, we

        always trigger blocking waiting in operation routines to wait until

        no. of active requests becomes zero. When the value is positive, we

        do blocking waiting in operation routines to wait until no. of

        active requests being reduced to this value.

    Default: 65536

MPIR_CVAR_CH3_RMA_POKE_PROGRESS_REQ_THRESHOLD

    Aliases: MPIR_PARAM_CH3_RMA_POKE_PROGRESS_REQ_THRESHOLD

             MPICH_CH3_RMA_POKE_PROGRESS_REQ_THRESHOLD

    Description: Threshold at which the RMA implementation attempts to

        complete requests while completing RMA operations and while using

        the lazy synchonization approach.  Change this value if programs

        fail because they run out of requests or other internal resources

    Default: 128

MPIR_CVAR_CH3_RMA_OP_WIN_POOL_SIZE

    Aliases: MPIR_PARAM_CH3_RMA_OP_WIN_POOL_SIZE

             MPICH_CH3_RMA_OP_WIN_POOL_SIZE

    Description: Size of the window-private RMA operations pool (in number

        of operations) that stores information about RMA operations that

        could not be issued immediately.  Requires a positive value.

    Default: 256

MPIR_CVAR_CH3_RMA_OP_GLOBAL_POOL_SIZE

    Aliases: MPIR_PARAM_CH3_RMA_OP_GLOBAL_POOL_SIZE

             MPICH_CH3_RMA_OP_GLOBAL_POOL_SIZE

    Description: Size of the Global RMA operations pool (in number of

        operations) that stores information about RMA operations that could

        not be issued immediatly.  Requires a positive value.

    Default: 16384

MPIR_CVAR_CH3_RMA_TARGET_WIN_POOL_SIZE

    Aliases: MPIR_PARAM_CH3_RMA_TARGET_WIN_POOL_SIZE

             MPICH_CH3_RMA_TARGET_WIN_POOL_SIZE

    Description: Size of the window-private RMA target pool (in number of

        targets) that stores information about RMA targets that could not

        be issued immediately.  Requires a positive value.

    Default: 256

MPIR_CVAR_CH3_RMA_TARGET_GLOBAL_POOL_SIZE

    Aliases: MPIR_PARAM_CH3_RMA_TARGET_GLOBAL_POOL_SIZE

             MPICH_CH3_RMA_TARGET_GLOBAL_POOL_SIZE

    Description: Size of the Global RMA targets pool (in number of targets)

        that stores information about RMA targets that could not be issued

        immediatly.  Requires a positive value.

    Default: 16384

MPIR_CVAR_CH3_RMA_TARGET_LOCK_ENTRY_WIN_POOL_SIZE

    Aliases: MPIR_PARAM_CH3_RMA_TARGET_LOCK_ENTRY_WIN_POOL_SIZE

             MPICH_CH3_RMA_TARGET_LOCK_ENTRY_WIN_POOL_SIZE

    Description: Size of the window-private RMA lock entries pool (in

        number of lock entries) that stores information about RMA lock

        requests that could not be satisfied immediatly.  Requires a

        positive value.

    Default: 256

MPIR_CVAR_ENABLE_FT

    Aliases: MPIR_PARAM_ENABLE_FT

             MPICH_ENABLE_FT

    Description: Enable fault tolerance functions

    Default: 0

MPIR_CVAR_NEMESIS_SHM_EAGER_MAX_SZ

    Aliases: MPIR_PARAM_NEMESIS_SHM_EAGER_MAX_SZ

             MPICH_NEMESIS_SHM_EAGER_MAX_SZ

    Description: This cvar controls the message size at which Nemesis

        switches from eager to rendezvous mode for shared memory. If this

        cvar is set to -1, then Nemesis will choose an appropriate value.

    Default: -1

MPIR_CVAR_NEMESIS_SHM_READY_EAGER_MAX_SZ

    Aliases: MPIR_PARAM_NEMESIS_SHM_READY_EAGER_MAX_SZ

             MPICH_NEMESIS_SHM_READY_EAGER_MAX_SZ

    Description: This cvar controls the message size at which Nemesis

        switches from eager to rendezvous mode for ready-send messages.  If

        this cvar is set to -1, then ready messages will always be sent

        eagerly.  If this cvar is set to -2, then Nemesis will choose an

        appropriate value.

    Default: -2

MPIR_CVAR_NEMESIS_ENABLE_CKPOINT

    Aliases: MPIR_PARAM_NEMESIS_ENABLE_CKPOINT

             MPICH_NEMESIS_ENABLE_CKPOINT

    Description: If true, enables checkpointing support and returns an

        error if checkpointing library cannot be initialized.

    Default: 0

MPIR_CVAR_NEMESIS_NETMOD

    Aliases: MPIR_PARAM_NEMESIS_NETMOD

             MPICH_NEMESIS_NETMOD

    Description: If non-empty, this cvar specifies which network module

        should be used for communication. This variable is

        case-insensitive.

    Default: ""

MPIR_CVAR_NEMESIS_LMT_DMA_THRESHOLD

    Aliases: MPIR_PARAM_NEMESIS_LMT_DMA_THRESHOLD

             MPICH_NEMESIS_LMT_DMA_THRESHOLD

    Description: Messages larger than this size will use the "dma" (knem)

        intranode LMT implementation, if it is enabled and available.

    Default: 2097152

MPIR_CVAR_POLLS_BEFORE_YIELD

    Aliases: MPIR_PARAM_POLLS_BEFORE_YIELD

             MPICH_POLLS_BEFORE_YIELD

    Description: When MPICH is in a busy waiting loop, it will periodically

        call a function to yield the processor.  This cvar sets the number

        of loops before the yield function is called.  A value of 0

        disables yielding.

    Default: 1000

MPIR_CVAR_OFI_USE_PROVIDER

    Aliases: MPIR_PARAM_OFI_USE_PROVIDER

             MPICH_OFI_USE_PROVIDER

    Description: If non-null, choose an OFI provider by name

    Default: NULL

MPIR_CVAR_OFI_DUMP_PROVIDERS

    Aliases: MPIR_PARAM_OFI_DUMP_PROVIDERS

             MPICH_OFI_DUMP_PROVIDERS

    Description: If true, dump provider information at init

    Default: 0

MPIR_CVAR_CH3_INTERFACE_HOSTNAME

    Aliases: MPIR_PARAM_CH3_INTERFACE_HOSTNAME

             MPICH_CH3_INTERFACE_HOSTNAME

             MPIR_CVAR_INTERFACE_HOSTNAME

             MPIR_PARAM_INTERFACE_HOSTNAME

             MPICH_INTERFACE_HOSTNAME

    Description: If non-NULL, this cvar specifies the IP address that other

        processes should use when connecting to this process. This cvar is

        mutually exclusive with the MPIR_CVAR_CH3_NETWORK_IFACE cvar and it

        is an error to set them both.

    Default: NULL

MPIR_CVAR_CH3_PORT_RANGE

    Aliases: MPIR_PARAM_CH3_PORT_RANGE

             MPICH_CH3_PORT_RANGE

             MPIR_CVAR_PORTRANGE

             MPIR_CVAR_PORT_RANGE

             MPIR_PARAM_PORTRANGE

             MPIR_PARAM_PORT_RANGE

             MPICH_PORTRANGE

             MPICH_PORT_RANGE

    Description: The MPIR_CVAR_CH3_PORT_RANGE environment variable allows

        you to specify the range of TCP ports to be used by the process

        manager and the MPICH library. The format of this variable is

        <low>:<high>.  To specify any available port, use 0:0.

    Default: {0,0}

MPIR_CVAR_NEMESIS_TCP_NETWORK_IFACE

    Aliases: MPIR_PARAM_NEMESIS_TCP_NETWORK_IFACE

             MPICH_NEMESIS_TCP_NETWORK_IFACE

             MPIR_CVAR_NETWORK_IFACE

             MPIR_PARAM_NETWORK_IFACE

             MPICH_NETWORK_IFACE

    Description: If non-NULL, this cvar specifies which pseudo-ethernet

        interface the tcp netmod should use (e.g., "eth1", "ib0"). Note,

        this is a Linux-specific cvar. This cvar is mutually exclusive with

        the MPIR_CVAR_CH3_INTERFACE_HOSTNAME cvar and it is an error to set

        them both.

    Default: NULL

MPIR_CVAR_NEMESIS_TCP_HOST_LOOKUP_RETRIES

    Aliases: MPIR_PARAM_NEMESIS_TCP_HOST_LOOKUP_RETRIES

             MPICH_NEMESIS_TCP_HOST_LOOKUP_RETRIES

    Description: This cvar controls the number of times to retry the

        gethostbyname() function before giving up.

    Default: 10

MPIR_CVAR_NEMESIS_MXM_BULK_CONNECT

    Aliases: MPIR_PARAM_NEMESIS_MXM_BULK_CONNECT

             MPICH_NEMESIS_MXM_BULK_CONNECT

    Description: If true, force mxm to connect all processes at

        initialization time.

    Default: 0

MPIR_CVAR_NEMESIS_MXM_BULK_DISCONNECT

    Aliases: MPIR_PARAM_NEMESIS_MXM_BULK_DISCONNECT

             MPICH_NEMESIS_MXM_BULK_DISCONNECT

    Description: If true, force mxm to disconnect all processes at

        finalization time.

    Default: 0

MPIR_CVAR_NEMESIS_MXM_HUGEPAGE

    Aliases: MPIR_PARAM_NEMESIS_MXM_HUGEPAGE

             MPICH_NEMESIS_MXM_HUGEPAGE

    Description: If true, mxm tries detecting hugepage support.  On HPC-X

        2.3 and earlier, this might cause problems on Ubuntu and other

        platforms even if the system provides hugepage support.

    Default: 0