Pipe PMDA
=========

This PMDA exports output from commands specified in a configuration
file.  Parameters can be passed to the command at the time it is
started, via the pipe.command.params metrics and the output is sent
to the pipe.firehouse event metric.

The default configuration file is $PCP_PMDAS_DIR/pipe/pipe.conf and
it should contain one line for each command from which you wish to
capture output.  Each line contains an instance identifier, a user
account under which the command should run, and the actual command.
The parameters are specified using ordinal shell notation ($1, $2,
... $N), for example:

$ cat $PCP_PMDAS_DIR/pipe/pipe.conf
# instance      user      command
rw_syscalls     root      perf script rw-by-file $1
bdev_trace      root      btrace -w $1 /dev/$2

[access]
allow user bob : *;
allow user jane : bdev_trace;
allow group perf : rw_syscalls;

bob$ pmval -i bdev_trace -x '5 sda' pipe.firehose 
 8,2  5  1  0.000000000 25227  A  WS 734332384 + 24 <- (253,2) 734330336
 8,0  5  2  0.000000414 25227  A  WS 735358432 + 24 <- (8,2) 734332384
 8,0  5  3  0.000000756 25227  Q  WS 735358432 + 24 [qemu-kvm]
 [...5 seconds worth]
bob$ 

Metrics
=======

The file ./help contains descriptions for all of the metrics exported
by this PMDA.

Once the PMDA has been installed, the following command will list all
the available metrics and their explanatory "help" text:

	$ pminfo -fT pipe

Installation
============

 +  # cd $PCP_PMDAS_DIR/pipe

 +  Check that there is no clash in the Performance Metrics Domain
    defined in ./domain.h and the other PMDAs currently in use (see
    $PCP_PMCDCONF_PATH).  If there is, edit ./domain.h to choose another
    domain number.

 +  Then simply use

	# ./Install

    and choose both the "collector" and "monitor" installation
    configuration options -- everything else is automated.

De-installation
===============

 +  Simply use

        # cd $PCP_PMDAS_DIR/pipe
	# ./Remove

Troubleshooting
===============

 +  After installing or restarting the agent, the PMCD log file
    ($PCP_LOG_DIR/pmcd/pmcd.log) and the PMDA log file
    ($PCP_LOG_DIR/pmcd/pipe.log) should be checked for any warnings
    or errors.
