dpdk

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Published: Feb 27, 2023 License: MIT Imports: 15 Imported by: 0

README

Data Plane Development Kit (DPDK) Input Plugin

The dpdk plugin collects metrics exposed by applications built with Data Plane Development Kit which is an extensive set of open source libraries designed for accelerating packet processing workloads.

DPDK provides APIs that enable exposing various statistics from the devices used by DPDK applications and enable exposing KPI metrics directly from applications. Device statistics include e.g. common statistics available across NICs, like: received and sent packets, received and sent bytes etc. In addition to this generic statistics, an extended statistics API is available that allows providing more detailed, driver-specific metrics that are not available as generic statistics.

DPDK Release 20.05 introduced updated telemetry interface that enables DPDK libraries and applications to provide their telemetry. This is referred to as v2 version of this socket-based telemetry interface. This release enabled e.g. reading driver-specific extended stats (/ethdev/xstats) via this new interface.

DPDK Release 20.11 introduced reading via v2 interface common statistics (/ethdev/stats) in addition to existing (/ethdev/xstats).

The example usage of v2 telemetry interface can be found in Telemetry User Guide. A variety of DPDK Sample Applications is also available for users to discover and test the capabilities of DPDK libraries and to explore the exposed metrics.

DPDK Version Info: This plugin uses this v2 interface to read telemetry data from applications build with DPDK version >= 20.05. The default configuration include reading common statistics from /ethdev/stats that is available from DPDK version >= 20.11. When using DPDK 20.05 <= version < DPDK 20.11 it is recommended to disable querying /ethdev/stats by setting corresponding exclude_commands configuration option. NOTE: Since DPDK will most likely run with root privileges, the socket telemetry interface exposed by DPDK will also require root access. This means that either access permissions have to be adjusted for socket telemetry interface to allow Telegraf to access it, or Telegraf should run with root privileges. NOTE: The DPDK socket must exist for Telegraf to start successfully. Telegraf will attempt to connect to the DPDK socket during the initialization phase.

Global configuration options

In addition to the plugin-specific configuration settings, plugins support additional global and plugin configuration settings. These settings are used to modify metrics, tags, and field or create aliases and configure ordering, etc. See the CONFIGURATION.md for more details.

Configuration

# Reads metrics from DPDK applications using v2 telemetry interface.
[[inputs.dpdk]]
  ## Path to DPDK telemetry socket. This shall point to v2 version of DPDK
  ## telemetry interface.
  # socket_path = "/var/run/dpdk/rte/dpdk_telemetry.v2"

  ## Duration that defines how long the connected socket client will wait for
  ## a response before terminating connection.
  ## This includes both writing to and reading from socket. Since it's local
  ## socket access to a fast packet processing application, the timeout should
  ## be sufficient for most users.
  ## Setting the value to 0 disables the timeout (not recommended)
  # socket_access_timeout = "200ms"

  ## Enables telemetry data collection for selected device types.
  ## Adding "ethdev" enables collection of telemetry from DPDK NICs
  ## (stats, xstats, link_status).
  ## Adding "rawdev" enables collection of telemetry from DPDK Raw Devices
  ## (xstats).
  # device_types = ["ethdev"]

  ## List of custom, application-specific telemetry commands to query
  ## The list of available commands depend on the application deployed.
  ## Applications can register their own commands via telemetry library API
  ## http://doc.dpdk.org/guides/prog_guide/telemetry_lib.html#registering-commands
  ## For L3 Forwarding with Power Management Sample Application this could be:
  ##   additional_commands = ["/l3fwd-power/stats"]
  # additional_commands = []

  ## Allows turning off collecting data for individual "ethdev" commands.
  ## Remove "/ethdev/link_status" from list to gather link status metrics.
  [inputs.dpdk.ethdev]
    exclude_commands = ["/ethdev/link_status"]

  ## When running multiple instances of the plugin it's recommended to add a
  ## unique tag to each instance to identify metrics exposed by an instance
  ## of DPDK application. This is useful when multiple DPDK apps run on a
  ## single host.
  ##  [inputs.dpdk.tags]
  ##    dpdk_instance = "my-fwd-app"

This plugin offers multiple configuration options, please review examples below for additional usage information.

Example: Minimal Configuration for NIC metrics

This configuration allows getting metrics for all devices reported via /ethdev/list command:

  • /ethdev/stats - basic device statistics (since DPDK 20.11)
  • /ethdev/xstats - extended device statistics
  • /ethdev/link_status - up/down link status
[[inputs.dpdk]]
  device_types = ["ethdev"]

Since this configuration will query /ethdev/link_status it's recommended to increase timeout to socket_access_timeout = "10s".

The plugin collecting interval should be adjusted accordingly (e.g. interval = "30s").

Checking link status depending on underlying implementation may take more time to complete. This configuration can be used to exclude this telemetry command to allow faster response for metrics.

[[inputs.dpdk]]
  device_types = ["ethdev"]

  [inputs.dpdk.ethdev]
    exclude_commands = ["/ethdev/link_status"]

A separate plugin instance with higher timeout settings can be used to get /ethdev/link_status independently. Consult Independent NIC link status configuration and Getting metrics from multiple DPDK instances running on same host examples for further details.

This configuration allows getting /ethdev/link_status using separate configuration, with higher timeout.

[[inputs.dpdk]]
  interval = "30s"
  socket_access_timeout = "10s"
  device_types = ["ethdev"]

  [inputs.dpdk.ethdev]
    exclude_commands = ["/ethdev/stats", "/ethdev/xstats"]
Example: Getting application-specific metrics

This configuration allows reading custom metrics exposed by applications. Example telemetry command obtained from L3 Forwarding with Power Management Sample Application.

[[inputs.dpdk]]
  device_types = ["ethdev"]
  additional_commands = ["/l3fwd-power/stats"]

  [inputs.dpdk.ethdev]
    exclude_commands = ["/ethdev/link_status"]

Command entries specified in additional_commands should match DPDK command format:

  • Command entry format: either command or command,params for commands that expect parameters, where comma (,) separates command from params.
  • Command entry length (command with params) should be < 1024 characters.
  • Command length (without params) should be < 56 characters.
  • Commands have to start with /.

Providing invalid commands will prevent the plugin from starting. Additional commands allow duplicates, but they will be removed during execution so each command will be executed only once during each metric gathering interval.

Example: Getting metrics from multiple DPDK instances on same host

This configuration allows getting metrics from two separate applications exposing their telemetry interfaces via separate sockets. For each plugin instance a unique tag [inputs.dpdk.tags] allows distinguishing between them.

# Instance #1 - L3 Forwarding with Power Management Application
[[inputs.dpdk]]
  socket_path = "/var/run/dpdk/rte/l3fwd-power_telemetry.v2"
  device_types = ["ethdev"]
  additional_commands = ["/l3fwd-power/stats"]

  [inputs.dpdk.ethdev]
    exclude_commands = ["/ethdev/link_status"]

  [inputs.dpdk.tags]
    dpdk_instance = "l3fwd-power"

# Instance #2 - L2 Forwarding with Intel Cache Allocation Technology (CAT)
# Application
[[inputs.dpdk]]
  socket_path = "/var/run/dpdk/rte/l2fwd-cat_telemetry.v2"
  device_types = ["ethdev"]

[inputs.dpdk.ethdev]
  exclude_commands = ["/ethdev/link_status"]

  [inputs.dpdk.tags]
    dpdk_instance = "l2fwd-cat"

This utilizes Telegraf's standard capability of adding custom tags to input plugin's measurements.

Metrics

The DPDK socket accepts command,params requests and returns metric data in JSON format. All metrics from DPDK socket become flattened using Telegraf's JSON Flattener and exposed as fields. If DPDK response contains no information (is empty or is null) then such response will be discarded.

NOTE: Since DPDK allows registering custom metrics in its telemetry framework the JSON response from DPDK may contain various sets of metrics. While metrics from /ethdev/stats should be most stable, the /ethdev/xstats may contain driver-specific metrics (depending on DPDK application configuration). The application-specific commands like /l3fwd-power/stats can return their own specific set of metrics.

Example Output

The output consists of plugin name (dpdk), and a set of tags that identify querying hierarchy:

dpdk,host=dpdk-host,dpdk_instance=l3fwd-power,command=/ethdev/stats,params=0 [fields] [timestamp]
Tag Description
host hostname of the machine (consult Telegraf Agent configuration for additional details)
dpdk_instance custom tag from [inputs.dpdk.tags] (optional)
command executed command (without params)
params command parameter, e.g. for /ethdev/stats it is the id of NIC as exposed by /ethdev/list. For DPDK app that uses 2 NICs the metrics will output e.g. params=0, params=1.

When running plugin configuration below...

[[inputs.dpdk]]
  device_types = ["ethdev"]
  additional_commands = ["/l3fwd-power/stats"]
  [inputs.dpdk.tags]
    dpdk_instance = "l3fwd-power"

...expected output for dpdk plugin instance running on host named host=dpdk-host:

dpdk,command=/ethdev/stats,dpdk_instance=l3fwd-power,host=dpdk-host,params=0 q_opackets_0=0,q_ipackets_5=0,q_errors_11=0,ierrors=0,q_obytes_5=0,q_obytes_10=0,q_opackets_10=0,q_ipackets_4=0,q_ipackets_7=0,q_ipackets_15=0,q_ibytes_5=0,q_ibytes_6=0,q_ibytes_9=0,obytes=0,q_opackets_1=0,q_opackets_11=0,q_obytes_7=0,q_errors_5=0,q_errors_10=0,q_ibytes_4=0,q_obytes_6=0,q_errors_1=0,q_opackets_5=0,q_errors_3=0,q_errors_12=0,q_ipackets_11=0,q_ipackets_12=0,q_obytes_14=0,q_opackets_15=0,q_obytes_2=0,q_errors_8=0,q_opackets_12=0,q_errors_0=0,q_errors_9=0,q_opackets_14=0,q_ibytes_3=0,q_ibytes_15=0,q_ipackets_13=0,q_ipackets_14=0,q_obytes_3=0,q_errors_13=0,q_opackets_3=0,q_ibytes_0=7092,q_ibytes_2=0,q_ibytes_8=0,q_ipackets_8=0,q_ipackets_10=0,q_obytes_4=0,q_ibytes_10=0,q_ibytes_13=0,q_ibytes_1=0,q_ibytes_12=0,opackets=0,q_obytes_1=0,q_errors_15=0,q_opackets_2=0,oerrors=0,rx_nombuf=0,q_opackets_8=0,q_ibytes_11=0,q_ipackets_3=0,q_obytes_0=0,q_obytes_12=0,q_obytes_11=0,q_obytes_13=0,q_errors_6=0,q_ipackets_1=0,q_ipackets_6=0,q_ipackets_9=0,q_obytes_15=0,q_opackets_7=0,q_ibytes_14=0,ipackets=98,q_ipackets_2=0,q_opackets_6=0,q_ibytes_7=0,imissed=0,q_opackets_4=0,q_opackets_9=0,q_obytes_8=0,q_obytes_9=0,q_errors_4=0,q_errors_14=0,q_opackets_13=0,ibytes=7092,q_ipackets_0=98,q_errors_2=0,q_errors_7=0 1606310780000000000
dpdk,command=/ethdev/stats,dpdk_instance=l3fwd-power,host=dpdk-host,params=1 q_opackets_0=0,q_ipackets_5=0,q_errors_11=0,ierrors=0,q_obytes_5=0,q_obytes_10=0,q_opackets_10=0,q_ipackets_4=0,q_ipackets_7=0,q_ipackets_15=0,q_ibytes_5=0,q_ibytes_6=0,q_ibytes_9=0,obytes=0,q_opackets_1=0,q_opackets_11=0,q_obytes_7=0,q_errors_5=0,q_errors_10=0,q_ibytes_4=0,q_obytes_6=0,q_errors_1=0,q_opackets_5=0,q_errors_3=0,q_errors_12=0,q_ipackets_11=0,q_ipackets_12=0,q_obytes_14=0,q_opackets_15=0,q_obytes_2=0,q_errors_8=0,q_opackets_12=0,q_errors_0=0,q_errors_9=0,q_opackets_14=0,q_ibytes_3=0,q_ibytes_15=0,q_ipackets_13=0,q_ipackets_14=0,q_obytes_3=0,q_errors_13=0,q_opackets_3=0,q_ibytes_0=7092,q_ibytes_2=0,q_ibytes_8=0,q_ipackets_8=0,q_ipackets_10=0,q_obytes_4=0,q_ibytes_10=0,q_ibytes_13=0,q_ibytes_1=0,q_ibytes_12=0,opackets=0,q_obytes_1=0,q_errors_15=0,q_opackets_2=0,oerrors=0,rx_nombuf=0,q_opackets_8=0,q_ibytes_11=0,q_ipackets_3=0,q_obytes_0=0,q_obytes_12=0,q_obytes_11=0,q_obytes_13=0,q_errors_6=0,q_ipackets_1=0,q_ipackets_6=0,q_ipackets_9=0,q_obytes_15=0,q_opackets_7=0,q_ibytes_14=0,ipackets=98,q_ipackets_2=0,q_opackets_6=0,q_ibytes_7=0,imissed=0,q_opackets_4=0,q_opackets_9=0,q_obytes_8=0,q_obytes_9=0,q_errors_4=0,q_errors_14=0,q_opackets_13=0,ibytes=7092,q_ipackets_0=98,q_errors_2=0,q_errors_7=0 1606310780000000000
dpdk,command=/ethdev/xstats,dpdk_instance=l3fwd-power,host=dpdk-host,params=0 out_octets_encrypted=0,rx_fcoe_mbuf_allocation_errors=0,tx_q1packets=0,rx_priority0_xoff_packets=0,rx_priority7_xoff_packets=0,rx_errors=0,mac_remote_errors=0,in_pkts_invalid=0,tx_priority3_xoff_packets=0,tx_errors=0,rx_fcoe_bytes=0,rx_flow_control_xon_packets=0,rx_priority4_xoff_packets=0,tx_priority2_xoff_packets=0,rx_illegal_byte_errors=0,rx_xoff_packets=0,rx_management_packets=0,rx_priority7_dropped=0,rx_priority4_dropped=0,in_pkts_unchecked=0,rx_error_bytes=0,rx_size_256_to_511_packets=0,tx_priority4_xoff_packets=0,rx_priority6_xon_packets=0,tx_priority4_xon_to_xoff_packets=0,in_pkts_delayed=0,rx_priority0_mbuf_allocation_errors=0,out_octets_protected=0,tx_priority7_xon_to_xoff_packets=0,tx_priority1_xon_to_xoff_packets=0,rx_fcoe_no_direct_data_placement_ext_buff=0,tx_priority6_xon_to_xoff_packets=0,flow_director_filter_add_errors=0,rx_total_packets=99,rx_crc_errors=0,flow_director_filter_remove_errors=0,rx_missed_errors=0,tx_size_64_packets=0,rx_priority3_dropped=0,flow_director_matched_filters=0,tx_priority2_xon_to_xoff_packets=0,rx_priority1_xon_packets=0,rx_size_65_to_127_packets=99,rx_fragment_errors=0,in_pkts_notusingsa=0,rx_q0bytes=7162,rx_fcoe_dropped=0,rx_priority1_dropped=0,rx_fcoe_packets=0,rx_priority5_xoff_packets=0,out_pkts_protected=0,tx_total_packets=0,rx_priority2_dropped=0,in_pkts_late=0,tx_q1bytes=0,in_pkts_badtag=0,rx_multicast_packets=99,rx_priority6_xoff_packets=0,tx_flow_control_xoff_packets=0,rx_flow_control_xoff_packets=0,rx_priority0_xon_packets=0,in_pkts_untagged=0,tx_fcoe_packets=0,rx_priority7_mbuf_allocation_errors=0,tx_priority0_xon_to_xoff_packets=0,tx_priority5_xon_to_xoff_packets=0,tx_flow_control_xon_packets=0,tx_q0packets=0,tx_xoff_packets=0,rx_size_512_to_1023_packets=0,rx_priority3_xon_packets=0,rx_q0errors=0,rx_oversize_errors=0,tx_priority4_xon_packets=0,tx_priority5_xoff_packets=0,rx_priority5_xon_packets=0,rx_total_missed_packets=0,rx_priority4_mbuf_allocation_errors=0,tx_priority1_xon_packets=0,tx_management_packets=0,rx_priority5_mbuf_allocation_errors=0,rx_fcoe_no_direct_data_placement=0,rx_undersize_errors=0,tx_priority1_xoff_packets=0,rx_q0packets=99,tx_q2packets=0,tx_priority6_xon_packets=0,rx_good_packets=99,tx_priority5_xon_packets=0,tx_size_256_to_511_packets=0,rx_priority6_dropped=0,rx_broadcast_packets=0,tx_size_512_to_1023_packets=0,tx_priority3_xon_to_xoff_packets=0,in_pkts_unknownsci=0,in_octets_validated=0,tx_priority6_xoff_packets=0,tx_priority7_xoff_packets=0,rx_jabber_errors=0,tx_priority7_xon_packets=0,tx_priority0_xon_packets=0,in_pkts_unusedsa=0,tx_priority0_xoff_packets=0,mac_local_errors=33,rx_total_bytes=7162,in_pkts_notvalid=0,rx_length_errors=0,in_octets_decrypted=0,rx_size_128_to_255_packets=0,rx_good_bytes=7162,tx_size_65_to_127_packets=0,rx_mac_short_packet_dropped=0,tx_size_1024_to_max_packets=0,rx_priority2_mbuf_allocation_errors=0,flow_director_added_filters=0,tx_multicast_packets=0,rx_fcoe_crc_errors=0,rx_priority1_xoff_packets=0,flow_director_missed_filters=0,rx_xon_packets=0,tx_size_128_to_255_packets=0,out_pkts_encrypted=0,rx_priority4_xon_packets=0,rx_priority0_dropped=0,rx_size_1024_to_max_packets=0,tx_good_bytes=0,rx_management_dropped=0,rx_mbuf_allocation_errors=0,tx_xon_packets=0,rx_priority3_xoff_packets=0,tx_good_packets=0,tx_fcoe_bytes=0,rx_priority6_mbuf_allocation_errors=0,rx_priority2_xon_packets=0,tx_broadcast_packets=0,tx_q2bytes=0,rx_priority7_xon_packets=0,out_pkts_untagged=0,rx_priority2_xoff_packets=0,rx_priority1_mbuf_allocation_errors=0,tx_q0bytes=0,rx_size_64_packets=0,rx_priority5_dropped=0,tx_priority2_xon_packets=0,in_pkts_nosci=0,flow_director_removed_filters=0,in_pkts_ok=0,rx_l3_l4_xsum_error=0,rx_priority3_mbuf_allocation_errors=0,tx_priority3_xon_packets=0 1606310780000000000
dpdk,command=/ethdev/xstats,dpdk_instance=l3fwd-power,host=dpdk-host,params=1 tx_priority5_xoff_packets=0,in_pkts_unknownsci=0,tx_q0packets=0,tx_total_packets=0,rx_crc_errors=0,rx_priority4_xoff_packets=0,rx_priority5_dropped=0,tx_size_65_to_127_packets=0,rx_good_packets=98,tx_priority6_xoff_packets=0,tx_fcoe_bytes=0,out_octets_protected=0,out_pkts_encrypted=0,rx_priority1_xon_packets=0,tx_size_128_to_255_packets=0,rx_flow_control_xoff_packets=0,rx_priority7_xoff_packets=0,tx_priority0_xon_to_xoff_packets=0,rx_broadcast_packets=0,tx_priority1_xon_packets=0,rx_xon_packets=0,rx_fragment_errors=0,tx_flow_control_xoff_packets=0,tx_q0bytes=0,out_pkts_untagged=0,rx_priority4_xon_packets=0,tx_priority5_xon_packets=0,rx_priority1_xoff_packets=0,rx_good_bytes=7092,rx_priority4_mbuf_allocation_errors=0,in_octets_decrypted=0,tx_priority2_xon_to_xoff_packets=0,rx_priority3_dropped=0,tx_multicast_packets=0,mac_local_errors=33,in_pkts_ok=0,rx_illegal_byte_errors=0,rx_xoff_packets=0,rx_q0errors=0,flow_director_added_filters=0,rx_size_256_to_511_packets=0,rx_priority3_xon_packets=0,rx_l3_l4_xsum_error=0,rx_priority6_dropped=0,in_pkts_notvalid=0,rx_size_64_packets=0,tx_management_packets=0,rx_length_errors=0,tx_priority7_xon_to_xoff_packets=0,rx_mbuf_allocation_errors=0,rx_missed_errors=0,rx_priority1_mbuf_allocation_errors=0,rx_fcoe_no_direct_data_placement=0,tx_priority3_xoff_packets=0,in_pkts_delayed=0,tx_errors=0,rx_size_512_to_1023_packets=0,tx_priority4_xon_packets=0,rx_q0bytes=7092,in_pkts_unchecked=0,tx_size_512_to_1023_packets=0,rx_fcoe_packets=0,in_pkts_nosci=0,rx_priority6_mbuf_allocation_errors=0,rx_priority1_dropped=0,tx_q2packets=0,rx_priority7_dropped=0,tx_size_1024_to_max_packets=0,rx_management_packets=0,rx_multicast_packets=98,rx_total_bytes=7092,mac_remote_errors=0,tx_priority3_xon_packets=0,rx_priority2_mbuf_allocation_errors=0,rx_priority5_mbuf_allocation_errors=0,tx_q2bytes=0,rx_size_128_to_255_packets=0,in_pkts_badtag=0,out_pkts_protected=0,rx_management_dropped=0,rx_fcoe_bytes=0,flow_director_removed_filters=0,tx_priority2_xoff_packets=0,rx_fcoe_crc_errors=0,rx_priority0_mbuf_allocation_errors=0,rx_priority0_xon_packets=0,rx_fcoe_dropped=0,tx_priority1_xon_to_xoff_packets=0,rx_size_65_to_127_packets=98,rx_q0packets=98,tx_priority0_xoff_packets=0,rx_priority6_xon_packets=0,rx_total_packets=98,rx_undersize_errors=0,flow_director_missed_filters=0,rx_jabber_errors=0,in_pkts_invalid=0,in_pkts_late=0,rx_priority5_xon_packets=0,tx_priority4_xoff_packets=0,out_octets_encrypted=0,tx_q1packets=0,rx_priority5_xoff_packets=0,rx_priority6_xoff_packets=0,rx_errors=0,in_octets_validated=0,rx_priority3_xoff_packets=0,tx_priority4_xon_to_xoff_packets=0,tx_priority5_xon_to_xoff_packets=0,tx_flow_control_xon_packets=0,rx_priority0_dropped=0,flow_director_filter_add_errors=0,tx_q1bytes=0,tx_priority6_xon_to_xoff_packets=0,flow_director_matched_filters=0,tx_priority2_xon_packets=0,rx_fcoe_mbuf_allocation_errors=0,rx_priority2_xoff_packets=0,tx_priority7_xoff_packets=0,rx_priority0_xoff_packets=0,rx_oversize_errors=0,in_pkts_notusingsa=0,tx_size_64_packets=0,rx_size_1024_to_max_packets=0,tx_priority6_xon_packets=0,rx_priority2_dropped=0,rx_priority4_dropped=0,rx_priority7_mbuf_allocation_errors=0,rx_flow_control_xon_packets=0,tx_good_bytes=0,tx_priority3_xon_to_xoff_packets=0,rx_total_missed_packets=0,rx_error_bytes=0,tx_priority7_xon_packets=0,rx_mac_short_packet_dropped=0,tx_priority1_xoff_packets=0,tx_good_packets=0,tx_broadcast_packets=0,tx_xon_packets=0,in_pkts_unusedsa=0,rx_priority2_xon_packets=0,in_pkts_untagged=0,tx_fcoe_packets=0,flow_director_filter_remove_errors=0,rx_priority3_mbuf_allocation_errors=0,tx_priority0_xon_packets=0,rx_priority7_xon_packets=0,rx_fcoe_no_direct_data_placement_ext_buff=0,tx_xoff_packets=0,tx_size_256_to_511_packets=0 1606310780000000000
dpdk,command=/ethdev/link_status,dpdk_instance=l3fwd-power,host=dpdk-host,params=0 status="UP",speed=10000,duplex="full-duplex" 1606310780000000000
dpdk,command=/ethdev/link_status,dpdk_instance=l3fwd-power,host=dpdk-host,params=1 status="UP",speed=10000,duplex="full-duplex" 1606310780000000000
dpdk,command=/l3fwd-power/stats,dpdk_instance=l3fwd-power,host=dpdk-host empty_poll=49506395979901,full_poll=0,busy_percent=0 1606310780000000000

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