Provided by: pcp_6.2.0-1.1build4_amd64 
NAME
PCPCompat, pcp-collectl, pmmgr, pmwebd - backward-compatibility in the Performance Co-Pilot (PCP)
INTRODUCTION
The Performance Co-Pilot (PCP) is a toolkit designed for monitoring and managing system-level
performance. These services are distributed and scalable to accommodate the most complex system
configurations and performance problems.
In order to achieve these goals effectively, protocol and on-disk compatibility is provided between
different versions of PCP. It is feasible (and indeed encouraged) to use current PCP tools to
interrogate any remote, down-rev or up-rev pmcd(1) and also to replay any historical PCP archive (the PCP
testsuite includes PCP archives created over 20 years ago!).
From time to time the PCP developers deprecate and remove PCP utilities, replacing them with new versions
of utilities providing comparable features. This page describes replacement utilities for historical PCP
tools.
PYTHON2
PCP provides python(1) interfaces for the PMAPI(3) (Performance Metrics API), the PMDA(3) API
(Performance Metrics Domain Agents), the mmv_stats_register(3) API (Memory-Mapped Values) and PCP archive
creation LOGIMPORT(3) API.
With python version 2 reaching end-of-life in 2020 we have deprecated the python version 2 interfaces in
PCP (shipped, but no longer supported). In the next major release of PCP (v7) version 2 support will be
retired (completely removed). All PCP APIs and python-based tools support python version 3 and have for
several years - upgrading is strongly recommended.
QT4
PCP provides optional graphical user interfaces built on the cross-platform Qt library, particularly
pmchart(1) and pmtime(1).
With Qt v4 reaching end-of-life in 2015 we have removed support for all versions before Qt v5. In
addition, some features are missing in early versions of Qt v5 that are now mandatory when building and
using PCP Qt tools. As a result the minimum required version of Qt for PCP v6 and beyond is now Qt 5.6.
NSS
Versions of PCP before v6 used a combination of both Mozilla NSS (Network Security Services) and OpenSSL
for the encryption component of the secure sockets functionality. Starting with PCP v6 this has been
simplified into exclusive use of OpenSSL for all use of encryption across PCP. This change affects
configuration of optional functionality in pmcd(1) and PMAPI(3) client tools using secure sockets.
The net effect of this change is that encryption is configured in the same ways, using the same
certificates, across the HTTPS functionality in pmproxy(1), as well as the encrypted PCP protocol
functionality between pmcd, pmproxy and PMAPI client tools. Additionally, the Redis service used by
pmseries(1) and pmproxy also exclusively uses OpenSSL, and in a manner similar to PCP, which makes
administering these services significantly simpler.
SAR2PCP, IOSTAT2PCP
The sar2pcp(1) and iostat2pcp(1) utilities are deprecated, and will be retired in a future version of PCP
(v7). This is being replaced by native support for generating PCP archives within the tools of the
sysstat package (which provides sar itself, as well as the sadf utility which produces PCP archives via
the -l option).
PMLOGCONF-SETUP
Earlier versions of PCP (prior to v5.1.1) provided a shell script that was used internally by
pmlogconf(1), located in the PCP_BINADM_DIR directory, named pmlogconf-setup. This script has been
retired. The equivalent functionality remains available in the unlikely event it should be needed via
the -s or --setup option to pmlogconf(1).
The version 1 pmlogconf-setup configuration file format (from IRIX) was also retired in this release,
after more than 10 years of automatic transition to version 2 format by pmlogconf.
PMMGR
The standalone PCP daemon manager pmmgr has been retired from PCP v5.2.0 onward. It was phased out in
favour of the simpler pmfind(1) service for setting up pmie(1) and pmlogger(1) ``farms'' of discovered
PCP collector systems with pmfind_check(1). The new mechanisms, especially when integrated with systemd,
require no additional daemons and are better integrated with the pmie and pmlogger service management
used elsewhere in PCP.
PCP-COLLECTL
The pcp-collectl utility has been superceded by pmrep(1) from PCP v5 onward.
The equivalent of pcp-collectl subsystem reporting is achieved as follows:
pmrep :collectl-sc
Processor subsystem view.
pmrep :collectl-sm
Memory subsystem view.
pmrep :collectl-sd
Aggregate disks view.
pmrep :collectl-sD
Per-disk-device view.
pmrep :collectl-dm-sD
Device mapper view.
pmrep :collectl-sn
Network subsystem view.
PCP-WEBAPPS
The standalone web applications packaged with older PCP versions have been superceded by grafana-
server(1) with the grafana-pcp plugin https://github.com/performancecopilot/grafana-pcp.
This plugin provides an implementation of the Vector application, as well as data sources for
pmdabpftrace(1) (bpftrace(8) scripts) and pmseries(1) (fast, scalable Redis-based time series analysis).
PMWEBD
The pmwebd daemon has been superceded by pmproxy(1) from PCP v5 onward.
By default, pmproxy will now listen on both its original port (44322) and the PCP web API port (44323)
when the time series support is built.
pmproxy provides a compatible implementation of the live PMWEBAPI(3) interfaces used traditionally by the
Vector web application (see the ``PCP-WEBAPPS'' section). It also provides extensions to the original
pmwebd REST APIs (such as derived metrics, namespace lookups and instance domain profiles), support for
the HTTPS protocol, and fast, scalable time series querying using the pmseries(1) REST API and redis-
server(1).
The partial Graphite API emulation provided by pmwebd has not been re-implemented - applications wishing
to use similar services could use the scalable time series REST APIs described on PMWEBAPI(3).
SEE ALSO
pcp(1), pmcd(1), iostat2pcp(1), sar2pcp(1), pmrep(1), pmfind(1), pmfind_check(1), pmlogconf(1),
pmproxy(1), pmseries(1), pmdabpftrace(1), python(1), redis-server(1), grafana-server(1),
mmv_stats_register(3), LOGIMPORT(3), PMAPI(3), PMDA(3) and PMWEBAPI(3).
Performance Co-Pilot PCP PCPCOMPAT(1)