PMGENMAP(1)PMGENMAP(1)NAMEpmgenmap - generate C code to simplify handling of performance metrics
SYNOPSISpmgenmap [infile]
DESCRIPTION
Given one or more lists of metric names in infile or on standard input,
pmgenmap generates C declarations and cpp(1) macros suitable for use
across the Performance Metrics Programming Interface (PMAPI) on stan‐
dard output.
The declarations produced by pmgenmap simplify the coding for client
applications using the PMAPI.
The input should consist of one or more lists of metric names of the
form
listname {
metricname1 symbolname1
metricname2 symbolname2
...
}
which will generate C and cpp(1) declarations of the form
char *listname[] = {
#define symbolname1 0
"metricname1",
#define symbolname2 1
"metricname2",
...
};
The array declarations produced are suitable as parameters to pmLookup‐
Name(3) and the #defined constants may be used to index the vsets in
the pmResult structure returned by a pmFetch(3) call.
Obviously, listname must conform to the C identifier naming rules, each
symbolname must conform to the cpp(1) macro naming rules, and each met‐
ricname is expected to be a valid performance metrics name (see pmns(4)
for more details).
The input may include sh-style comment lines, i.e. with a `#' as the
first non-blank character of a line, and these are translated on output
to either single line or multi-line C comments in the K&R style. For
example, the input:
# leading block of multi-line comments
# initialization group
foo {
a.b.c ONE
d.e.f.g TWO
# embedded block of multi-lines
# comments and boring pad text
xx.yy.zz THREE
}
# trailing single line comment
Produces the output:
/*
* leading block of multi-line comments
* initialization group
*/
char *foo[] = {
#define ONE 0
"a.b.c",
#define TWO 1
"d.e.f.g",
/*
* embedded block of multi-lines
* comments and boring pad text
*/
#define THREE 2
"xx.yy.zz",
};
/* trailing single line comment */
EXAMPLE
For brevity we have removed the error handling code, and assumed the
chosen metrics do not have multiple values.
The input file
mystats {
kernel.percpu.cpu.idle IDLE
kernel.percpu.cpu.sys SYS
kernel.percpu.cpu.user USER
hinv.ncpu NCPU
}
produces the following C code, suitable for #include-ing
/*
* Performance Metrics Name Space Map
* Built by pmgenmap from the file
* mystats.metrics
* on Wed Dec 28 19:44:17 EST 1994
*
* Do not edit this file!
*/
char *mystats[] = {
#define IDLE 0
"kernel.percpu.cpu.idle",
#define SYS 1
"kernel.percpu.cpu.sys",
#define USER 2
"kernel.percpu.cpu.user",
#define NCPU 3
"hinv.ncpu",
};
Using the code generated by pmgenmap, we are now able to easily obtain
metrics from the Performance Metrics Collection Subsystem (PMCS) as
follows:
#define MAX_PMID 4
int trip = 0;
int numpmid = sizeof(mystats)/sizeof(mystats[0]);
double duration;
pmResult *resp;
pmResult *prev;
pmID pmidlist[MAX_PMID];
pmNewContext(PM_CONTEXT_HOST, "localhost");
pmLookupName(numpmid, mystats, pmidlist);
pmFetch(numpmid, pmidlist, &resp);
printf("%d CPUs: %d usr %d sys %d idle0,
resp->vset[NCPU]->vlist[0].value.lval,
resp->vset[USER]->vlist[0].value.lval,
resp->vset[SYS]->vlist[0].value.lval,
resp->vset[IDLE]->vlist[0].value.lval);
Some calls to ensure portability have been removed from the code above
for the sake of clarity - the example above should not be used as a
template for programming. In particular, the raw values of the metrics
were used when pmLookupDesc(3) should have been called to determine the
semantics of each metric.
More complete examples that demonstrate the use of pmgenmap which may
be used as a basis for program development are included in the PCP
demos, e.g. $PCP_DEMOS_DIR/pmclient.
FILES
$PCP_VAR_DIR/pmns/*
default PMNS specification files
PCP ENVIRONMENT
Environment variables with the prefix PCP_ are used to parameterize the
file and directory names used by PCP. On each installation, the file
/etc/pcp.conf contains the local values for these variables. The
$PCP_CONF variable may be used to specify an alternative configuration
file, as described in pcp.conf(4).
SEE ALSOcpp(1), PMAPI(3), pmFetch(3), pmLookupName(3), pmNewContext(3),
pcp.conf(4), pcp.env(4) and pmns(4).
Performance Co-Pilot SGI PMGENMAP(1)
