QA output created by 716
dbpmda> open pipe /usr/bin/env perl pmdasimple.pl
Start env PMDA: /usr/bin/env perl pmdasimple.pl
dbpmda> # on some platforms this may take a while ...
dbpmda> wait 2
dbpmda> getdesc on
dbpmda> desc simple.numfetch
PMID: 253.0.0
    Data Type: 32-bit unsigned int  InDom: PM_INDOM_NULL 0xffffffff
    Semantics: instant  Units: none
dbpmda> fetch simple.numfetch
PMID(s): 253.0.0
pmResult ... numpmid: 1
  253.0.0 (simple.numfetch): numval: 1 valfmt: 0 vlist[]:
   value NUMBER
dbpmda> text simple.numfetch
PMID: 253.0.0
[Number of pmFetch operations.]
The cumulative number of pmFetch operations directed to the "simple"
PMDA.

This counter may be modified with pmstore(1).
dbpmda> desc simple.color
PMID: 253.0.1
    Data Type: 32-bit int  InDom: 253.0 0x3f400000
    Semantics: instant  Units: none
dbpmda> fetch simple.color
PMID(s): 253.0.1
pmResult ... numpmid: 1
  253.0.1 (simple.color): numval: 3 valfmt: 0 vlist[]:
    inst [0 or ???] value NUMBER
    inst [1 or ???] value NUMBER
    inst [2 or ???] value NUMBER
dbpmda> text simple.color
PMID: 253.0.1
[Metrics which increment with each fetch]
This metric has 3 instances, designated "red", "green" and "blue".

The value of the metric is monotonic increasing in the range NUMBER to
255, then back to 0.  The different instances have different starting
values, namely 0 (red), 100 (green) and 200 (blue).

The metric values my be altered using pmstore(1).
dbpmda> desc simple.now
PMID: 253.2.4
    Data Type: 32-bit unsigned int  InDom: 253.1 0x3f400001
    Semantics: instant  Units: none
dbpmda> fetch simple.now
PMID(s): 253.2.4
pmResult ... numpmid: 1
  253.2.4 (simple.now): numval: 3 valfmt: 0 vlist[]:
    inst [0 or ???] value NUMBER
    inst [1 or ???] value NUMBER
    inst [2 or ???] value NUMBER
dbpmda> text simple.now
PMID: 253.2.4
[Time of day with a configurable instance domain]
The value reflects the current time of day through a dynamically
reconfigurable instance domain.  On each metric value fetch request,
the agent checks to see whether the configuration file in
$PCP_PMDAS_DIR/simple/simple.conf has been modified - if it has then
the file is re-parsed and the instance domain for this metric is again
constructed according to its contents.

This configuration file contains a single line of comma-separated time
tokens from this set:
  "sec"  (seconds after the minute),
  "min"  (minutes after the hour),
  "hour" (hour since midnight).

An example configuration file could be:  sec,min,hour
and in this case the simple.now metric would export values
for the three instances "sec", "min" and "hour" corresponding
respectively to the components seconds, minutes and hours of the
current time of day.

The instance domain reflects each token present in the file, and the
values reflect the time at which the PMDA processes the fetch.
dbpmda> instance 253.0
pmInDom: 253.0
[  0] inst: 0 name: "red"
[  1] inst: 1 name: "green"
[  2] inst: 2 name: "blue"
dbpmda> text indom 253.1
pmInDom: 253.1
[Dynamic instance domain "time" for simple PMDA]
An instance domain which is computed on-the-fly for exporting current time
information.  Refer to the help text for simple.now for a more complete
explanation.
dbpmda> 
