1PMSNAP(1) General Commands Manual PMSNAP(1)
2
6 pmsnap - generate performance summary snapshot images
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9 $PCP_BINADM_DIR/pmsnap [-NV?] [-c configs] [-C dir] [-f format] [-n
10 names] [-o dir]
11
13 pmsnap is a shell script that is normally run periodically from
14 crontab(1) to generate graphic images of pmchart(1) performance charts.
15 These images can be in any of the supported pmchart formats, including
16 png, bmp, and jpeg, and may be incorporated into the content offered by
17 the local web server. By default pmsnap generates no textual output
18 unless some error or warning condition is encountered.
19 pmsnap generates images according to its control file, $PCP_PMSNAPCON‐
21 TROL_PATH (or dir/control if the -C option is specified), and uses ar‐
22 chive logs created by pmlogger(1) or PCP archive folios created by
23 pmafm(1) and pmlogger_check(1). Before attempting to configure pmsnap,
24 it is strongly recommended that pmlogger be configured according to the
25 descriptions in pmlogger_daily(1), pmlogger_check(1) and pmlogger(1).
26 Once pmlogger has been configured, it is necessary to configure pmsnap
28 as follows;
29 1. Edit the control file $PCP_PMSNAPCONTROL_PATH. The syntax of
31 this file is described in the comment at the head of the file
32 and an example is supplied for one and twelve hour "Summary"
33 performance charts for the local host. Suitable arguments for
34 pmchart are also described in the comment. The user should con‐
35 sult pmchart for further details. Note that when pmsnap is run,
36 it globally substitutes the string LOCALHOSTNAME with the name
37 of the local host in the control file.
38 2. Test the configuration by running
40 $PCP_BINADM_DIR/pmsnap.
41 Without any arguments pmsnap will process every non-comment line
42 in $PCP_PMSNAPCONTROL_PATH. The output images will be placed in
43 the files named in the first field of each line in the control
44 file, with the file format appended if necessary. If these file
45 names do not start with / or . then they are assumed relative
46 to dir, as specified with the -o option. The default dir is the
47 current directory. Note that if pmlogger has only been recently
48 started (within about the last 15 minutes), snapshot images may
49 not be produced and no error messages will be issued - the rea‐
50 son is that pmchart can not use very short archives and hence,
51 neither can pmsnap. For debugging purposes the -V flag should
52 be used.
53 3. Add an appropriate entry for pmsnap in the root user's crontab.
55 An example is supplied in $PCP_VAR_DIR/config/pmlogger/crontab.
56 4. Incorporate the pmsnap images into the local WWW content. Usu‐
58 ally, WWW pages use images that are relative to a particular
59 document root, so it is often convenient to use the -o command
60 line option to specify a sub-directory of the local WWW content,
61 and then create a web page in this directory that shows the
62 snapshot images with text and other content appropriate to the
63 local environment.
64 A sample HTML page, suitable for the Summary snapshot may be found in
66 $PCP_VAR_DIR/config/pmsnap/Summary.html.
67 Although pmsnap attempts to flush stdio(3) output buffers in the rele‐
69 vant pmlogger processes before generating snapshots images, this may
70 fail for assorted reasons and no error message will be given.
71 pmsnap should not be invoked immediately after pmlogger_daily has
73 rolled the logs because the new archive logs will be too short to
74 obtain meaningful results. Note however that pmsnap will not report
75 errors from pmchart about not being able to comply with the -A option
76 on very short archives. In these cases no error will be reported and
77 no output images will be produced.
78
80 The available command line options are:
81 -c config-pattern
83 Only process lines in the control file which match the config-pat‐
84 tern regular expression in the Config column.
85 -C dir
87 The control file is located in the directory dir rather than in
88 the default $PCP_PMSNAPCONTROL_PATH location.
89 -f format
91 Set output image format. The defaults format is png.
92 -n name-pattern
94 Only process lines in the control file which match the name-pat‐
95 tern regular expression (see egrep(1)) in the Name column.
96 -N Enable a ``show me'' mode, where the actions are echoed, but not
98 executed, in the style of ``make -n''. Using -N in conjunction
99 with -V maximizes the diagnostic capabilities for debugging.
100 -o dir
102 The output images having file names which do not start with / or .
103 will be placed in a directory relative to dir, otherwise the out‐
104 put directory is relative to the current directory (i.e. the
105 default value for dir is ./). Note that dir must be a writable
106 directory path and may be on an NFS or CIFS file system.
107 -V Enable verbose mode.
109 -? Display usage message and exit.
111 When either -n or -c are used, pmsnap will only process lines in the
113 control file which match all the supplied patterns. If no patterns are
114 given, then all lines will be processed. These arguments allow multi‐
115 ple entries for pmsnap in crontab so that different performance summary
116 images can be generated at different times or with different frequen‐
117 cies.
118
120 $PCP_PMSNAPCONTROL_PATH
121 pmsnap control file
122 $PCP_VAR_DIR/config/pmsnap/Summary
124 summary view for pmchart
125 $PCP_VAR_DIR/config/pmsnap/Summary.html
127 sample HTML page for summary snapshot
128 $PCP_LOG_DIR/pmlogger/<hostname>/Latest
130 PCP archive folio for the host hostname, as generated by pmlog‐
131 ger_check
132 $PCP_VAR_DIR/config/pmlogger/crontab
134 example crontab entry
135
137 cron(1), crontab(1), egrep(1), pmafm(1), pmchart(1), pmlc(1), pmlog‐
138 ger(1) and pmlogger_daily(1).
139Performance Co-Pilot PMSNAP(1)