Chapter 10. Setting up graphical representation of PCP metrics Using a combination of pcp , grafana , pcp redis , pcp bpftrace , and pcp vector provides graphical representation of the live data or data collected by Performance Co-Pilot (PCP). 10.1. Setting up PCP with pcp-zeroconf This procedure describes how to set up PCP on a system with the pcp-zeroconf package. Once the pcp-zeroconf package is installed, the system records the default set of metrics into archived files. Procedure Install the pcp-zeroconf package: Verification Ensure that the pmlogger service is active, and starts archiving the metrics: Additional resources pmlogger man page on your system Monitoring performance with Performance Co-Pilot 10.2. Setting up a grafana-server Grafana generates graphs that are accessible from a browser. The grafana-server is a back-end server for the Grafana dashboard. It listens, by default, on all interfaces, and provides web services accessed through the web browser. The grafana-pcp plugin interacts with the pmproxy daemon in the backend. This procedure describes how to set up a grafana-server . Prerequisites PCP is configured. For more information, see Setting up PCP with pcp-zeroconf . Procedure Install the following packages: Restart and enable the following service: Open the server's firewall for network traffic to the Grafana service. Verification Ensure that the grafana-server is listening and responding to requests: Ensure that the grafana-pcp plugin is installed: Additional resources pmproxy(1) and grafana-server man pages on your system 10.3. Accessing the Grafana web UI This procedure describes how to access the Grafana web interface. Using the Grafana web interface, you can: add PCP Redis, PCP bpftrace, and PCP Vector data sources create dashboard view an overview of any useful metrics create alerts in PCP Redis Prerequisites PCP is configured. For more information, see Setting up PCP with pcp-zeroconf . The grafana-server is configured. For more information, see Setting up a grafana-server . Procedure On the client system, open a browser and access the grafana-server on port 3000 , using http://192.0.2.0 :3000 link. Replace 192.0.2.0 with your machine IP when accessing Grafana web UI from a remote machine, or with localhost when accessing the web UI locally. For the first login, enter admin in both the Email or username and Password field. Grafana prompts to set a New password to create a secured account. If you want to set it later, click Skip . From the menu, hover over the Configuration icon and then click Plugins . In the Plugins tab, type performance co-pilot in the Search by name or type text box and then click Performance Co-Pilot (PCP) plugin. In the Plugins / Performance Co-Pilot pane, click Enable . Click Grafana icon. The Grafana Home page is displayed. Figure 10.1. Home Dashboard Note The top corner of the screen has a similar icon, but it controls the general Dashboard settings . In the Grafana Home page, click Add your first data source to add PCP Redis, PCP bpftrace, and PCP Vector data sources. For more information about adding data source, see: To add pcp redis data source, view default dashboard, create a panel, and an alert rule, see Creating panels and alert in PCP Redis data source . To add pcp bpftrace data source and view the default dashboard, see Viewing the PCP bpftrace System Analysis dashboard . To add pcp vector data source, view the default dashboard, and to view the vector checklist, see Viewing the PCP Vector Checklist . Optional: From the menu, hover over the admin profile icon to change the Preferences including Edit Profile , Change Password , or to Sign out . Additional resources grafana-cli and grafana-server man pages on your system 10.4. Configuring PCP Redis Use the PCP Redis data source to: View data archives Query time series using pmseries language Analyze data across multiple hosts Prerequisites PCP is configured. For more information, see Setting up PCP with pcp-zeroconf . The grafana-server is configured. For more information, see Setting up a grafana-server . Mail transfer agent, for example, sendmail or postfix is installed and configured. Procedure Install the redis package: Note From Red Hat Enterprise Linux 8.4, Redis 6 is supported but the yum update command does not update Redis 5 to Redis 6. To update from Redis 5 to Redis 6, run: # yum module switch-to redis:6 Start and enable the following services: Restart the grafana-server : Verification Ensure that the pmproxy and redis are working: This command does not return any data if the redis package is not installed. Additional resources pmseries(1) man page on your system 10.5. Creating panels and alerts in PCP Redis data source After adding the PCP Redis data source, you can view the dashboard with an overview of useful metrics, add a query to visualize the load graph, and create alerts that help you to view the system issues after they occur. Prerequisites The PCP Redis is configured. For more information, see Configuring PCP Redis . The grafana-server is accessible. For more information, see Accessing the Grafana web UI . Procedure Log into the Grafana web UI. In the Grafana Home page, click Add your first data source . In the Add data source pane, type redis in the Filter by name or type text box and then click PCP Redis . In the Data Sources / PCP Redis pane, perform the following: Add http://localhost:44322 in the URL field and then click Save & Test . Click Dashboards tab Import PCP Redis: Host Overview to see a dashboard with an overview of any useful metrics. Figure 10.2. PCP Redis: Host Overview Add a new panel: From the menu, hover over the Create icon Dashboard Add new panel icon to add a panel. In the Query tab, select the PCP Redis from the query list instead of the selected default option and in the text field of A , enter metric, for example, kernel.all.load to visualize the kernel load graph. Optional: Add Panel title and Description , and update other options from the Settings . Click Save to apply changes and save the dashboard. Add Dashboard name . Click Apply to apply changes and go back to the dashboard. Figure 10.3. PCP Redis query panel Create an alert rule: In the PCP Redis query panel , click Alert and then click Create Alert . Edit the Name , Evaluate query , and For fields from the Rule , and specify the Conditions for your alert. Click Save to apply changes and save the dashboard. Click Apply to apply changes and go back to the dashboard. Figure 10.4. Creating alerts in the PCP Redis panel Optional: In the same panel, scroll down and click Delete icon to delete the created rule. Optional: From the menu, click Alerting icon to view the created alert rules with different alert statuses, to edit the alert rule, or to pause the existing rule from the Alert Rules tab. To add a notification channel for the created alert rule to receive an alert notification from Grafana, see Adding notification channels for alerts . 10.6. Adding notification channels for alerts By adding notification channels, you can receive an alert notification from Grafana whenever the alert rule conditions are met and the system needs further monitoring. You can receive these alerts after selecting any one type from the supported list of notifiers, which includes DingDing , Discord , Email , Google Hangouts Chat , HipChat , Kafka REST Proxy , LINE , Microsoft Teams , OpsGenie , PagerDuty , Prometheus Alertmanager , Pushover , Sensu , Slack , Telegram , Threema Gateway , VictorOps , and webhook . Prerequisites The grafana-server is accessible. For more information, see Accessing the Grafana web UI . An alert rule is created. For more information, see Creating panels and alert in PCP Redis data source . Configure SMTP and add a valid sender's email address in the grafana/grafana.ini file: Replace abc@gmail.com by a valid email address. Restart grafana-server Procedure From the menu, hover over the Alerting icon click Notification channels Add channel . In the Add notification channel details pane, perform the following: Enter your name in the Name text box Select the communication Type , for example, Email and enter the email address. You can add multiple email addresses using the ; separator. Optional: Configure Optional Email settings and Notification settings . Click Save . Select a notification channel in the alert rule: From the menu, hover over the Alerting icon and then click Alert rules . From the Alert Rules tab, click the created alert rule. On the Notifications tab, select your notification channel name from the Send to option, and then add an alert message. Click Apply . Additional resources Upstream Grafana documentation for alert notifications 10.7. Setting up authentication between PCP components You can setup authentication using the scram-sha-256 authentication mechanism, which is supported by PCP through the Simple Authentication Security Layer (SASL) framework. Note From Red Hat Enterprise Linux 8.3, PCP supports the scram-sha-256 authentication mechanism. Procedure Install the sasl framework for the scram-sha-256 authentication mechanism: Specify the supported authentication mechanism and the user database path in the pmcd.conf file: Create a new user: Replace metrics by your user name. Add the created user in the user database: To add the created user, you are required to enter the metrics account password. Set the permissions of the user database: Restart the pmcd service: Verification Verify the sasl configuration: Additional resources saslauthd(8) , pminfo(1) , and sha256 man pages on your system How can I setup authentication between PCP components, like PMDAs and pmcd in RHEL 8.2? (Red Hat Knowledgebase) 10.8. Installing PCP bpftrace Install the PCP bpftrace agent to introspect a system and to gather metrics from the kernel and user-space tracepoints. The bpftrace agent uses bpftrace scripts to gather the metrics. The bpftrace scripts use the enhanced Berkeley Packet Filter ( eBPF ). This procedure describes how to install a pcp bpftrace . Prerequisites PCP is configured. For more information, see Setting up PCP with pcp-zeroconf . The grafana-server is configured. For more information, see Setting up a grafana-server . The scram-sha-256 authentication mechanism is configured. For more information, see Setting up authentication between PCP components . Procedure Install the pcp-pmda-bpftrace package: Edit the bpftrace.conf file and add the user that you have created in Setting up authentication between PCP components : Replace metrics by your user name. Install bpftrace PMDA: The pmda-bpftrace is now installed, and can only be used after authenticating your user. For more information, see Viewing the PCP bpftrace System Analysis dashboard . Additional resources pmdabpftrace(1) and bpftrace man pages on your system 10.9. Viewing the PCP bpftrace System Analysis dashboard Using the PCP bpftrace data source, you can access the live data from sources which are not available as normal data from the pmlogger or archives In the PCP bpftrace data source, you can view the dashboard with an overview of useful metrics. Prerequisites The PCP bpftrace is installed. For more information, see Installing PCP bpftrace . The grafana-server is accessible. For more information, see Accessing the Grafana web UI . Procedure Log into the Grafana web UI. In the Grafana Home page, click Add your first data source . In the Add data source pane, type bpftrace in the Filter by name or type text box and then click PCP bpftrace . In the Data Sources / PCP bpftrace pane, perform the following: Add http://localhost:44322 in the URL field. Toggle the Basic Auth option and add the created user credentials in the User and Password field. Click Save & Test . Figure 10.5. Adding PCP bpftrace in the data source Click Dashboards tab Import PCP bpftrace: System Analysis to see a dashboard with an overview of any useful metrics. Figure 10.6. PCP bpftrace: System Analysis 10.10. Installing PCP Vector This procedure describes how to install a pcp vector . Prerequisites PCP is configured. For more information, see Setting up PCP with pcp-zeroconf . The grafana-server is configured. For more information, see Setting up a grafana-server . Procedure Install the bcc PMDA: Additional resources pmdabcc(1) man page on your system 10.11. Viewing the PCP Vector Checklist The PCP Vector data source displays live metrics and uses the pcp metrics. It analyzes data for individual hosts. After adding the PCP Vector data source, you can view the dashboard with an overview of useful metrics and view the related troubleshooting or reference links in the checklist. Prerequisites The PCP Vector is installed. For more information, see Installing PCP Vector . The grafana-server is accessible. For more information, see Accessing the Grafana web UI . Procedure Log into the Grafana web UI. In the Grafana Home page, click Add your first data source . In the Add data source pane, type vector in the Filter by name or type text box and then click PCP Vector . In the Data Sources / PCP Vector pane, perform the following: Add http://localhost:44322 in the URL field and then click Save & Test . Click Dashboards tab Import PCP Vector: Host Overview to see a dashboard with an overview of any useful metrics. Figure 10.7. PCP Vector: Host Overview From the menu, hover over the Performance Co-Pilot plugin and then click PCP Vector Checklist . In the PCP checklist, click help or warning icon to view the related troubleshooting or reference links. Figure 10.8. Performance Co-Pilot / PCP Vector Checklist 10.12. Using heatmaps in Grafana You can use heatmaps in Grafana to view histograms of your data over time, identify trends and patterns in your data, and see how they change over time. Each column within a heatmap represents a single histogram with different colored cells representing the different densities of observation of a given value within that histogram. Important This specific workflow is for the heatmaps in Grafana version 9.2.10 and later on RHEL8. Prerequisites PCP Redis is configured. For more information see Configuring PCP Redis . The grafana-server is accessible. For more information see Accessing the Grafana Web UI . The PCP Redis data source is configured. For more information see Creating panels and alerts in PCP Redis data source . Procedure Hover the cursor over the Dashboards tab and click + New dashboard . In the Add panel menu, click Add a new panel . In the Query tab: Select PCP Redis from the query list instead of the selected default option. In the text field of A , enter a metric, for example, kernel.all.load to visualize the kernel load graph. Click the visualization dropdown menu, which is set to Time series by default, and then click Heatmap . Optional: In the Panel Options dropdown menu, add a Panel Title and Description . In the Heatmap dropdown menu, under the Calculate from data setting, click Yes . Heatmap Optional: In the Colors dropdown menu, change the Scheme from the default Orange and select the number of steps (color shades). Optional: In the Tooltip dropdown menu, under the Show histogram (Y Axis) setting, click the toggle to display a cell's position within its specific histogram when hovering your cursor over a cell in the heatmap. For example: Show histogram (Y Axis) cell display 10.13. Troubleshooting Grafana issues It is sometimes neccesary to troubleshoot Grafana issues, such as, Grafana does not display any data, the dashboard is black, or similar issues. Procedure Verify that the pmlogger service is up and running by executing the following command: Verify if files were created or modified to the disk by executing the following command: Verify that the pmproxy service is running by executing the following command: Verify that pmproxy is running, time series support is enabled, and a connection to Redis is established by viewing the /var/log/pcp/pmproxy/pmproxy.log file and ensure that it contains the following text: Here, 1716 is the PID of pmproxy, which will be different for every invocation of pmproxy . Verify if the Redis database contains any keys by executing the following command: Verify if any PCP metrics are in the Redis database and pmproxy is able to access them by executing the following commands: Verify if there are any errors in the Grafana logs by executing the following command:

Commands:
yum install pcp-zeroconf
pcp | grep pmlogger pmlogger: primary logger: /var/log/pcp/pmlogger/ localhost.localdomain/20200401.00.12
yum install grafana grafana-pcp
systemctl restart grafana-server systemctl enable grafana-server
firewall-cmd --permanent --add-service=grafana success firewall-cmd --reload success
ss -ntlp | grep 3000 LISTEN 0 128 *:3000 *:* users:(("grafana-server",pid=19522,fd=7))
grafana-cli plugins ls | grep performancecopilot-pcp-app performancecopilot-pcp-app @ 3.1.0
yum module install redis:6
systemctl start pmproxy redis systemctl enable pmproxy redis
systemctl restart grafana-server
pmseries disk.dev.read 2eb3e58d8f1e231361fb15cf1aa26fe534b4d9df
vi /etc/grafana/grafana.ini [smtp] enabled = true from_address = abc@gmail.com
systemctl restart grafana-server.service
yum install cyrus-sasl-scram cyrus-sasl-lib
vi /etc/sasl2/pmcd.conf mech_list: scram-sha-256 sasldb_path: /etc/pcp/passwd.db
useradd -r metrics
saslpasswd2 -a pmcd metrics Password: Again (for verification):
chown root:pcp /etc/pcp/passwd.db chmod 640 /etc/pcp/passwd.db
systemctl restart pmcd
pminfo -f -h "pcp://127.0.0.1?username= metrics " disk.dev.read Password: disk.dev.read inst [0 or "sda"] value 19540
yum install pcp-pmda-bpftrace
vi /var/lib/pcp/pmdas/bpftrace/bpftrace.conf [dynamic_scripts] enabled = true auth_enabled = true allowed_users = root, metrics
cd /var/lib/pcp/pmdas/bpftrace/ ./Install Updating the Performance Metrics Name Space (PMNS) Terminate PMDA if already installed Updating the PMCD control file, and notifying PMCD Check bpftrace metrics have appeared ... 7 metrics and 6 values
cd /var/lib/pcp/pmdas/bcc ./Install [Wed Apr 1 00:27:48] pmdabcc(22341) Info: Initializing, currently in 'notready' state. [Wed Apr 1 00:27:48] pmdabcc(22341) Info: Enabled modules: [Wed Apr 1 00:27:48] pmdabcc(22341) Info: ['biolatency', 'sysfork', [...] Updating the Performance Metrics Name Space (PMNS) Terminate PMDA if already installed Updating the PMCD control file, and notifying PMCD Check bcc metrics have appeared ... 1 warnings, 1 metrics and 0 values
systemctl status pmlogger
ls /var/log/pcp/pmlogger/USD(hostname)/ -rlt total 4024 -rw-r--r--. 1 pcp pcp 45996 Oct 13 2019 20191013.20.07.meta.xz -rw-r--r--. 1 pcp pcp 412 Oct 13 2019 20191013.20.07.index -rw-r--r--. 1 pcp pcp 32188 Oct 13 2019 20191013.20.07.0.xz -rw-r--r--. 1 pcp pcp 44756 Oct 13 2019 20191013.20.30-00.meta.xz [..]
systemctl status pmproxy
pmproxy(1716) Info: Redis slots, command keys, schema version setup
redis-cli dbsize (integer) 34837
pmseries disk.dev.read 2eb3e58d8f1e231361fb15cf1aa26fe534b4d9df pmseries "disk.dev.read[count:10]" 2eb3e58d8f1e231361fb15cf1aa26fe534b4d9df [Mon Jul 26 12:21:10.085468000 2021] 117971 70e83e88d4e1857a3a31605c6d1333755f2dd17c [Mon Jul 26 12:21:00.087401000 2021] 117758 70e83e88d4e1857a3a31605c6d1333755f2dd17c [Mon Jul 26 12:20:50.085738000 2021] 116688 70e83e88d4e1857a3a31605c6d1333755f2dd17c [...]
redis-cli --scan --pattern "*USD(pmseries 'disk.dev.read')" pcp:metric.name:series:2eb3e58d8f1e231361fb15cf1aa26fe534b4d9df pcp:values:series:2eb3e58d8f1e231361fb15cf1aa26fe534b4d9df pcp:desc:series:2eb3e58d8f1e231361fb15cf1aa26fe534b4d9df pcp:labelvalue:series:2eb3e58d8f1e231361fb15cf1aa26fe534b4d9df pcp:instances:series:2eb3e58d8f1e231361fb15cf1aa26fe534b4d9df pcp:labelflags:series:2eb3e58d8f1e231361fb15cf1aa26fe534b4d9df
journalctl -e -u grafana-server -- Logs begin at Mon 2021-07-26 11:55:10 IST, end at Mon 2021-07-26 12:30:15 IST. -- Jul 26 11:55:17 localhost.localdomain systemd[1]: Starting Grafana instance Jul 26 11:55:17 localhost.localdomain grafana-server[1171]: t=2021-07-26T11:55:17+0530 lvl=info msg="Starting Grafana" logger=server version=7.3.6 c> Jul 26 11:55:17 localhost.localdomain grafana-server[1171]: t=2021-07-26T11:55:17+0530 lvl=info msg="Config loaded from" logger=settings file=/usr/s> Jul 26 11:55:17 localhost.localdomain grafana-server[1171]: t=2021-07-26T11:55:17+0530 lvl=info msg="Config loaded from" logger=settings file=/etc/g> [...]