генерировать код C для упрощения обработки показателей производительности (generate C code to simplify handling of performance metrics)
Имя (Name)
pmgenmap - generate C code to simplify handling of performance
metrics
Синопсис (Synopsis)
pmgenmap [infile]
Описание (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 standard 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
pmLookupName(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 metricname is expected to be a valid performance
metrics name (see PMNS(5) 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 */
Примеры (Examples)
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.
Файлы (Files)
$PCP_VAR_DIR/pmns/*
default PMNS specification files
Окружение PCP (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(5).
Смотри также (See also)
cpp(1), PMAPI(3), pmFetch(3), pmLookupName(3), pmNewContext(3),
pcp.conf(5), pcp.env(5) and PMNS(5).
