pshpstuningguidew p040105.doc Page 23
MEMORY_AFFINITY
Single Thread Usage(MP_SINGLE_THREAD)
Hints Filtered (MP_HINTS_FILTERED)
MPI-I/O Buffer Size (MP_IO_BUFFER_SIZE)
MPI-I/O Error Logging (MP_IO_ERRLOG)
MPI-I/O Node File (MP_IO_NODEFILE)
MPI-I/O Task List (MP_IO_TASKLIST)
System Checkpointable (CHECKPOINT)
LoadLeveler Gang Scheduler
DMA Receive FIFO Size (Bytes)
Max outsta ndi ng packets
LAPI Max Packet Size (Bytes)
LAPI Ack Threshold (MP_ACK_THRESH)
LAPI Max retransmit buf size (MP_REXMIT_BUF_SIZE)
LAPI Max retransmit buf count (MP_REXMIT_BUF_CNT)
LAPI Maximum Atom Size
LAPI use bulk transfer (MP_USE_BULK_XFER)
LAPI bulk min message size (MP_BULK_MIN_MSG_SIZE)
LAPI no debug timeout (MP_DEBUG_NOTIMEOUT)
Develop Mode (MP_EUIDEVELOP)
Standard Input Mode (MP_STDINMODE)
Standard Output Mode (MP_STDOUTMODE)
Statistics Collection Enabled (MP_STATISTICS)
Number of Service Variables set (MP_S_*)
Interrupt Delay (us) (MP_INTRDELAY)
Sync on Connect Usage (MP_SYNC_ON_CONNECT)
Internal Pipe Size (KBytes)(MP_PIPE_SIZE)
Ack Interval (count)(MP_ACK_INTERVAL)
LAPI Buffer Copy Size (MP_COPY_SEND_BUF_SIZE)
User Script Name (MP_PRINTENV)
Size of User Script Output
If MP_STATISTICS is set to yes, statistics are collected. However, t hese sta tistics are written
only when a call is made to mp_statistics_write, which takes a pointer to a file descriptor as its
sole argument. These statistics can be zeroed out with a call to mp_statistics_zero. This can be
used with calls to mp_statistics_write to determine the communication statistics in different
portions of the us er app licatio n . These s t atist i c s are us e ful for d etermin ing if th ere are ex cessi ve
packet retransmits, in addition to giving the total number of packets, messages, and data sent or
received. The late arrivals are useful in determining how often a receive was posted before the
matching message arrived. Early arrivals indicate how often a message is received before the
posting of the matching receive.
MP_STATISTICS take the values yes and print. If the value is set to print, the statistics
are printed for each task in the job at MPI_FINALIZE. If you set MP_STATISTICS to print,
you should also set MP_LABELIO to yes so you know which task each line of output came
from.
The following is a sample output of the statistics.