mads::process_metrics Class Reference

Read-only process resource metrics for a given PID. More...

#include <pm.hpp>

Public Types
using	pid_type = pid_t
	PID type used by the platform.
using	clock = std::chrono::steady_clock
	Steady clock type used internally.

Public Member Functions
	process_metrics (std::optional< pid_type > pid=std::nullopt)
	Construct metrics for a target process.
pid_type	pid () const noexcept
	Get the PID associated with this instance.
void	sample ()
	Take a new CPU usage sample for the target PID.
double	cpu_percent_total_capacity () const
	CPU usage as percentage of total machine capacity.
double	cpu_percent_per_core () const
	CPU usage scaled per logical core.
std::uint32_t	thread_count () const
	Get instantaneous number of threads in the target process.
std::uint64_t	ram_bytes () const
	Get resident memory usage (RSS / working set) in bytes.
std::uint32_t	cpu_count () const
	Get number of logical CPUs detected on the system.

Detailed Description

Read-only process resource metrics for a given PID.

Provides the following metrics for a target process:

• number of threads
• resident memory (RSS / working set)
• CPU load (relative to total machine capacity and per-core scale)

Note

For macOS, querying other PIDs may require elevated privileges (task_for_pid entitlement/root); otherwise metrics may be unavailable.

Definition at line 54 of file pm.hpp.

Member Typedef Documentation

clock

using mads::process_metrics::clock = std::chrono::steady_clock

Steady clock type used internally.

Definition at line 65 of file pm.hpp.

pid_type

using mads::process_metrics::pid_type = pid_t

PID type used by the platform.

Definition at line 57 of file pm.hpp.

Constructor & Destructor Documentation

process_metrics()

mads::process_metrics::process_metrics ( std::optional< pid_type >  pid = std::nullopt )

inlineexplicit

Construct metrics for a target process.

Parameters

pid	Optional PID; if not provided, the current process PID is used.

Definition at line 72 of file pm.hpp.

Member Function Documentation

cpu_count()

std::uint32_t mads::process_metrics::cpu_count ( ) const

inline

Get number of logical CPUs detected on the system.

Returns

Logical CPU count (>= 1).

Definition at line 255 of file pm.hpp.

cpu_percent_per_core()

double mads::process_metrics::cpu_percent_per_core ( ) const

inline

CPU usage scaled per logical core.

0..(100 * cpu_count), where 100 corresponds to one fully saturated logical core.

Returns

CPU percentage in range [0, 100*cpu_count()] (best-effort).

Note

Meaningful only after at least two calls to sample().

Definition at line 135 of file pm.hpp.

cpu_percent_total_capacity()

double mads::process_metrics::cpu_percent_total_capacity ( ) const

inline

CPU usage as percentage of total machine capacity.

0..100, where 100 means the process is using ~all CPU capacity across all logical CPUs (i.e., saturating the machine).

Returns

CPU percentage in range [0, 100] (best-effort).

Note

Meaningful only after at least two calls to sample().

Definition at line 122 of file pm.hpp.

pid()

pid_type mads::process_metrics::pid ( ) const

inlinenoexcept

Get the PID associated with this instance.

Returns

Target PID.

Definition at line 81 of file pm.hpp.

ram_bytes()

std::uint64_t mads::process_metrics::ram_bytes ( ) const

inline

Get resident memory usage (RSS / working set) in bytes.

• Windows: Working Set Size.
• Linux: RSS derived from /proc/<pid>/statm.
• macOS: resident_size from Mach task info.

Returns

Resident bytes; 0 if unavailable.

Definition at line 208 of file pm.hpp.

sample()

void mads::process_metrics::sample ( )

inline

Take a new CPU usage sample for the target PID.

Reads process CPU time and system CPU time, and updates internal deltas.

Note

CPU percentages returned by cpu_percent_*() are meaningful only after at least two calls to sample().

Definition at line 91 of file pm.hpp.

thread_count()

std::uint32_t mads::process_metrics::thread_count ( ) const

inline

Get instantaneous number of threads in the target process.

Returns

Thread count; 0 if unavailable (e.g., insufficient permissions).

Definition at line 145 of file pm.hpp.

References thread_count().

Referenced by thread_count().

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The documentation for this class was generated from the following file:

• src/gui/director/pm.hpp