1lamssi(7) LAM SSI OVERVIEW lamssi(7)
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6 LAM SSI - introduction to LAM System Services Interface (SSI)
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9 The SSI in LAM/MPI is used to select one (or more) system services
10 interfaces at run-time.
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13 LAM SSI instances are uniquely described in terms of "kinds" (also
14 referred to as "types") and "modules".
15 The "kind" refers to which set of system services the SSI instance will
17 apply to. For example, LAM currently has several kinds: "boot",
18 "coll", "cr" and "rpi". The "module" refers to a specific SSI instance
19 of a given kind. Each kind has o
20 boot modules are used to start the LAM run-time environment (i.e., they
22 provide the back-end functionality to lamboot(1)). boot modules are
23 discussed further in the lamssi_boot(7) man page.
24 coll modules provide back-end algorithms and functionality for the MPI
26 collective communications. coll modules are described in
27 lamssi_coll(7).
28 cr modules provide checkpoint/restart functionality for MPI jobs. See
30 lamssi_cr(7) for details.
31 rpi modules provide back-end functionality for MPI point-to-point com‐
33 munications. rpi modules are detailed in lamssi_rpi(7).
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36 The user can force SSI modules to be verbose by setting the
37 LAM_SSI_ssi_verbose environment variable before invoking mpirun, or by
38 using the -ssi command line switch to mpirun. For example:
39 mpirun -ssi ssi_verbose 1 C foo
41 Tell the SSI modules to be verbose, and default to sending their
42 output to stderr.
43 The ssi_verbose kind is a "pseudo-kind" in that it is used to pass
45 parameters to the main SSI meta-glue itself -- not to any particular
46 kind. It can take many different parameters to format where and how
47 the verbose output will be sent (note that at least one parameter must
48 be specified, even if it is an invalid parameter). Any combination of
49 the following parameters may follow the ssi_verbose kind (separated by
50 commas):
51 syslog
53 Send the verbose output to the syslog.
54 syslogpri:<priority>
56 Set the syslog output priority to <priority>. Using this paramter
57 implies the syslog parameter. The default priority is info
58 (LOG_INFO). Valid <priority> values are: notice (LOG_NOTICE),
59 info, and debug (LOG_DEBUG).
60 syslogid:<id>
62 Use the ID <id> for the syslog prefix.
63 stdout
65 Send the verbose output to stdout.
66 stderr
68 Send the verbose output to stderr.
69 file[:<filename>]
71 Send the verbose output to a file in the LAM per-user, per-node
72 meta information directory (usually located in /tmp). If <file‐
73 name> is specified, send the output to the file named lam-<file‐
74 name>. If <filename> is not specified, send the output to the file
75 named lam-ssi.txt.
76 fileappend
78 Append to the file when sending the verbose output (create the file
79 if it does not exist). If this parameter is not given, if the file
80 already exists, it will be overwritten. Using this parameter
81 implies the file parameter.
82 level:vlevel
84 Indicate the specific verbosity level to be used. Although the
85 specific meaning of the verbosity level is left up to individual
86 SSI modules, generally negative numbers mean no verbose messages, 0
87 means a minimal set of messages, and positive numbers mean more
88 messages (the greater the positive number, the more output messages
89 will be generated). If left unspecified any any other ssi_verbose
90 parameters are specified, the default level of 0 is used.
91 If multiple parameters are passed in ssi_verbose, the output will be
93 directed as implied by all the parameters. If no valid parameters are
94 passed (e.g., a single invalid parameter is passed), then output will
95 be directed to stderr by default.
96 Also note that as with all SSI parameters, all of these values may be
98 passed by setting the environment variable LAM_SSI_ssi_verbose before
99 invoking mpirun. However, parameters passed through "-ssi ssi_verbose"
100 will take precedence over environment variables.
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103 mpirun -ssi ssi_verbose 1 C foo
104 Since no valid parameters were passed, the verbose output will be
105 sent to stderr.
106 mpirun -ssi ssi_verbose file:output.txt,syslogpri:notice C foo
108 Send the verbose output to both the file lam-output.txt in the LAM
109 user meta directory as well as to the syslog with a priority of
110 LOG_NOTICE.
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113 lamssi_boot(7), lamssi_coll(7), lamssi_cr(7), lamssi_rpi(7), mpirun(1),
114 lamboot(1), recon(1), lamwipe(1), LAM User's Guide
115LAM 7.1.2 March, 2006 lamssi(7)