Impala Daemon Health Tests

Impala Daemon File Descriptors

This Impala Daemon health test checks that the number of file descriptors used does not rise above some percentage of the Impala Daemon file descriptor limit. A failure of this health test may indicate a bug in either Hadoop or Cloudera Manager. Contact Cloudera support. This test can be configured using the File Descriptor Monitoring Thresholds Impala Daemon monitoring setting.

Short Name: File Descriptors

Property Name Description Template Name Default Value Unit
File Descriptor Monitoring Thresholds The health test thresholds of the number of file descriptors used. Specified as a percentage of file descriptor limit. impalad_fd_thresholds critical:70.0, warning:50.0 PERCENT

Impala Daemon Host Health

This Impala Daemon health test factors in the health of the host upon which the Impala Daemon is running. A failure of this test means that the host running the Impala Daemon is experiencing some problem. See that host's status page for more details.This test can be enabled or disabled using the Impala Daemon Host Health Test Impala Daemon monitoring setting.

Short Name: Host Health

Property Name Description Template Name Default Value Unit
Impala Daemon Host Health Test When computing the overall Impala Daemon health, consider the host's health. impalad_host_health_enabled true no unit

Impala Daemon Impala Daemon Ready Check.

This is an Impala Daemon health test that checks if the Impala Daemon is ready to process queries. This check usually fails if the YARN Node Manager is not available. If the YARN Node Manager goes offline, no resources can be acquired and new queries cannot be run. This test can be configured using the Impala Daemon Ready Status Health Check and Impala Daemon Ready Status Startup Tolerance impalad monitoring settings.

Short Name: Impala Daemon Ready Check.

Property Name Description Template Name Default Value Unit
Impala Daemon Ready Status Health Check Enables the health check that determines if the Impala Daemon is ready to process queries. impalad_ready_status_check_enabled true no unit
Impala Daemon Ready Status Startup Tolerance The amount of time at Impala Daemon startup allowed for the Impala Daemon to start accepting new queries for processing. impalad_ready_status_check_startup_tolerance 180 SECONDS

Impala Daemon Log Directory Free Space

This Impala Daemon health test checks that the filesystem containing the log directory of this Impala Daemon has sufficient free space. This test can be configured using the Log Directory Free Space Monitoring Absolute Thresholds and Log Directory Free Space Monitoring Percentage Thresholds Impala Daemon monitoring settings.

Short Name: Log Directory Free Space

Property Name Description Template Name Default Value Unit
Log Directory Free Space Monitoring Absolute Thresholds The health test thresholds for monitoring of free space on the filesystem that contains this role's log directory. log_directory_free_space_absolute_thresholds critical:5.36870912E9, warning:1.073741824E10 BYTES
Log Directory Free Space Monitoring Percentage Thresholds The health test thresholds for monitoring of free space on the filesystem that contains this role's log directory. Specified as a percentage of the capacity on that filesystem. This setting is not used if a Log Directory Free Space Monitoring Absolute Thresholds setting is configured. log_directory_free_space_percentage_thresholds critical:never, warning:never PERCENT

Impala Daemon Process Status

This Impala Daemon health test checks that the Cloudera Manager Agent on the Impala Daemon host is heart beating correctly and that the process associated with the Impala Daemon role is in the state expected by Cloudera Manager. A failure of this health test may indicate a problem with the Impala Daemon process, a lack of connectivity to the Cloudera Manager Agent on the Impala Daemon host, or a problem with the Cloudera Manager Agent. This test can fail either because the Impala Daemon has crashed or because the Impala Daemon will not start or stop in a timely fashion. Check the Impala Daemon logs for more details. If the test fails because of problems communicating with the Cloudera Manager Agent on the Impala Daemon host, check the status of the Cloudera Manager Agent by running /etc/init.d/cloudera-scm-agent status on the Impala Daemon host, or look in the Cloudera Manager Agent logs on the Impala Daemon host for more details. This test can be enabled or disabled using the Impala Daemon Process Health Test Impala Daemon monitoring setting.

Short Name: Process Status

Property Name Description Template Name Default Value Unit
Impala Daemon Process Health Test Enables the health test that the Impala Daemon's process state is consistent with the role configuration impalad_scm_health_enabled true no unit

Impala Daemon Resident Set Size

This Impala Daemon health test checks that the size of the resident set does not rise above a configured threshold value. A failure of this health test may indicates that the Impala Daemon process is consuming more memory than expected. It is possible that that unexpected memory consumption may lead to swapping and decreased performance for processes running on the same host as this Impala Daemon. Increased Impala Daemon memory consumption may be caused by an increased workload on the Impala service, or by a bug in the Impala Daemon software. To avoid failures of this health test, free up additional memory for this Impala Daemon process and increase the Resident Set Size Thresholds monitoring setting. This test can be configured using the Resident Set Size Thresholds Impala Daemon monitoring setting.

Short Name: Resident Set Size

Property Name Description Template Name Default Value Unit
Resident Set Size Thresholds The health test thresholds on the resident size of the process. process_resident_set_size_thresholds critical:never, warning:never BYTES

Impala Daemon Scratch Directories Free Space

Impala scratch directories can be used by the Impala Daemon to write data, such as spilling information, to free up memory. This can be large amounts of data. This impalad health test checks whether the filesystems containing the scratch directories have sufficient free space. This test can be configured using the Impala Scratch Directories Free Space Monitoring Absolute Thresholds and Impala Scratch Directories Free Space Monitoring Percentage Thresholds impalad monitoring settings.

Short Name: Scratch Directories Free Space

Property Name Description Template Name Default Value Unit
Impala Scratch Directories Free Space Monitoring Absolute Thresholds The health test thresholds for monitoring of free space on the filesystems that contain Impala's scratch directories. impalad_scratch_directories_free_space_absolute_thresholds critical:5.36870912E9, warning:1.073741824E10 BYTES
Impala Scratch Directories Free Space Monitoring Percentage Thresholds Configures the health check thresholds for monitoring free space on the filesystems that contain Impala's scratch directories. Specified as a percentage of the capacity on the filesystem. This setting is not used if a Scratch Directories Free Space Monitoring Absolute Thresholds setting is configured. impalad_scratch_directories_free_space_percentage_thresholds critical:never, warning:never PERCENT

Impala Daemon StateStore Connectivity

This is an Impala Daemon health test that checks whether the StateStore considers the Impala Daemon alive. A failure of this health test may indicate that the Impala Daemon is having trouble communicating with the StateStore. Look in the Impala Daemon logs for more details. This test may return an unknown result if the Service Monitor is not able to communicate with the StateStore web server. Check the status of the StateStore web server and the Service Monitor logs if this test is returning an unknown result. This test can be enabled or disabled using the Impala Daemon Connectivity Health Test Impala Daemon monitoring setting. The Impala Daemon Connectivity Tolerance at Startup Impala Daemon monitoring setting and the Health Check Startup Tolerance StateStore monitoring setting can be used to control the test's tolerance windows around Impala Daemon and StateStore restarts respectively.

Short Name: StateStore Connectivity

Property Name Description Template Name Default Value Unit
Health Check Startup Tolerance The amount of time allowed after this role is started that failures of health checks that rely on communication with this role will be tolerated. statestore_startup_tolerance 5 MINUTES
Impala Daemon Connectivity Health Test Enables the health test that verifies the Impala Daemon is connected to the StateStore impalad_connectivity_health_enabled true no unit
Impala Daemon Connectivity Tolerance at Startup The amount of time to wait for the Impala Daemon to fully start up and connect to the StateStore before enforcing the connectivity check. impalad_connectivity_tolerance 180 SECONDS

Impala Daemon Unexpected Exits

This Impala Daemon health test checks that the Impala Daemon has not recently exited unexpectedly. The test returns "Bad" health if the number of unexpected exits goes above a critical threshold. For example, if this test is configured with a critical threshold of 1, this test would return "Good" health if there have been no unexpected exits recently. If there has been 1 or more unexpected exits recently, this test would return "Bad" health. This test can be configured using the Unexpected Exits Thresholds and Unexpected Exits Monitoring Period Impala Daemon monitoring settings.

Short Name: Unexpected Exits

Property Name Description Template Name Default Value Unit
Unexpected Exits Monitoring Period The period to review when computing unexpected exits. unexpected_exits_window 5 MINUTES
Unexpected Exits Thresholds The health test thresholds for unexpected exits encountered within a recent period specified by the unexpected_exits_window configuration for the role. unexpected_exits_thresholds critical:any, warning:never no unit

Impala Daemon Web Server Status

This health test checks that the role's web server is responding quickly to requests by the Cloudera Manager Agent, and that the Cloudera Manager Agent can collect metrics from the web server. Failure of this health test may indicate a problem with the web server of the Impala Daemon, a misconfiguration of the Impala Daemon or a problem with the Cloudera Manager Agent. Consult the Cloudera Manager Agent logs and the logs of the Impala Daemon for more detail. If the test's failure message indicates a communication problem, the Cloudera Manager Agent's HTTP requests to the Impala Daemon's web server are failing or timing out. If the test's failure message indicates an unexpected response, the Impala Daemon's web server responded to the Cloudera Manager Agent's request, but the response could not be interpreted for some reason. This test can be configured using the Web Metric Collection Impala Daemon monitoring setting.

Short Name: Web Server Status

Property Name Description Template Name Default Value Unit
Web Metric Collection Enables the health test that the Cloudera Manager Agent can successfully contact and gather metrics from the web server. impalad_web_metric_collection_enabled true no unit
Web Metric Collection Duration The health test thresholds on the duration of the metrics request to the web server. impalad_web_metric_collection_thresholds critical:never, warning:10000.0 MILLISECONDS