1PMEQUIVINDOM(3) Library Functions Manual PMEQUIVINDOM(3)
2
3
4
6 __pmEquivInDom - check if two instance domains are equivalent
7
9 #include <pcp/pmapi.h>
10 #include <pcp/libpcp.h>
11
12 int __pmEquivInDom(pmInDom a, pmInDom b)
13
14 cc ... -lpcp
15
17 This documentation is intended for internal Performance Co-Pilot (PCP)
18 developer use.
19
20 These interfaces are not part of the PCP APIs that are guaranteed to
21 remain fixed across releases, and at some point in the future they may
22 not work or may provide different semantics.
23
25 Within the Performance Co-Pilot (PCP) each instance domain is assigned
26 a unique Instance Domain Identifier (pmInDom). Internally a pmInDom is
27 constructed from 2 fields: the domain number (of the associated Perfor‐
28 mance Metrics Domain Agent, or PMDA) and the serial number (assigned by
29 the PMDA).
30
31 In some unusual circumstances different PMDAs may support independent
32 Instance Domains that are semantically equivalent, e.g. per CPU or per
33 process identifier. __pmEquivInDom provides a mechanism to determine
34 if Instance Domain a is equivalent to Instance Domain b.
35
36 The ``equivalence'' of Instance Domains is defined by an external con‐
37 figuration file, identified by the environment variable $PCP_INDOM_CON‐
38 FIG or $PCP_ETC_DIR/pcp/indom.config by default. The format for the
39 configuration file is defined in the CONFIGURATION FILE section below.
40
41 If $PCP_INDOM_CONFIG is an empty string, no equivalence mapping is
42 loaded.
43
45 An Instance Domain equivalence mapping file conforms to the folowing
46 syntax:
47 1. Lines beginning with optional white space, followied by ``#'' are
48 considered comments.
49 2. Blank lines are ignored.
50 3. Each remaining line defines one `equivalence map'' with a list of
51 white-space separated instance domains, each consisting of a number
52 (the domain number), a period ``.'' and a number (the serial num‐
53 ber). As a special case to ``match all serial numbers'', the se‐
54 rial number part can be ``*''.
55
56 The format of a pmInDom demands that a domain number is in the range 0
57 to 511, and a numeric serial number is in the range 0 to 4194303.
58
60 The return value is 1 if the Instance Domains are equivalent, else 0 if
61 they are not. In rare cases a return value of -1 is used to indicate
62 some problem (reported on standard error) in opening or parsing the
63 configuration file.
64
66 pmLookupInDom(3) and PMAPI(3).
67
68
69
70Performance Co-Pilot PCP PMEQUIVINDOM(3)