mh_metric
Analyze media heuristic metrics
TLDR
Print the code metrics for the specified files
Print the code metrics for the specified Octave files
Print the code metrics for the specified directory recursively
Print the code metrics for the current directory
Print the code metrics report in HTML or JSON format
SYNOPSIS
mh_metric [options] command [arguments]
PARAMETERS
-e event1[,event2,...]
Specify one or more PAPI events to measure. Multiple events are separated by commas.
-r iterations
Repeat the command multiple times and report the average metrics.
-u unit_mask
Specify the unit mask for the events.
-n num_domains
Set up counting domains.
-x exclusive
Count only on the current thread.
-v verbose
Enable verbose output.
I - Output the input arguments.
R - Output raw event sets as passed to PAPI.
D - Dump the contents of the event sets after initialization.
-V version
Print the PAPI version number and exit.
-h
Display help text and exit.
DESCRIPTION
The `mh_metric` command, part of the Performance Application Programming Interface (PAPI) tools, is used to measure and display hardware performance metrics on Linux systems. It provides access to a wide range of performance counters exposed by the underlying hardware, such as CPU cycles, cache misses, branch mispredictions, and floating-point operations. These metrics are crucial for performance analysis, identifying bottlenecks, and optimizing code for specific hardware architectures. By utilizing PAPI, `mh_metric` abstracts away the complexities of accessing hardware counters directly, providing a consistent interface across different platforms. It allows users to select specific events to monitor and display the results in a user-friendly format. The command is valuable for developers, system administrators, and performance engineers who need to understand the behavior of their applications at a low level and make informed decisions about optimization. Its output helps to reveal how efficiently code utilizes the CPU and memory subsystem, leading to better performance and resource utilization. It is commonly used in conjunction with other performance analysis tools like perf or gprof to provide a more complete picture of application behavior.
CAVEATS
The availability of specific PAPI events depends on the underlying hardware and the PAPI installation. Root privileges may be required to access certain performance counters. The performance counters may affect the overhead of the application being monitored, especially with increased complexity of events being monitored.
EVENT NAMING CONVENTIONS
PAPI events are typically named using a hierarchical structure. Use `papi_avail` to list the available events and their descriptions on your system.
EXAMPLE USAGE
Measure CPU cycles and cache misses for the `ls -l` command:
mh_metric -e PAPI_TOT_CYC,PAPI_L1_DCM ls -l