Metadata for tracking instance tier location. More...

#include <hsm_types.h>

Collaboration diagram for kcenon::pacs::storage::tier_metadata:

Public Member Functions
auto	age () const -> std::chrono::system_clock::duration
	Get the age of the instance (time since storage)

auto	time_since_access () const -> std::chrono::system_clock::duration
	Get the time since last access.

auto	should_migrate (const tier_policy &policy, storage_tier target_tier) const -> bool
	Check if instance is eligible for migration to a target tier.

Public Attributes
std::string	sop_instance_uid
	SOP Instance UID of the DICOM instance.

storage_tier	current_tier {storage_tier::hot}
	Current storage tier.

std::chrono::system_clock::time_point	stored_at
	Timestamp when instance was stored.

std::optional< std::chrono::system_clock::time_point >	last_accessed
	Timestamp of last access (retrieve operation) nullopt if never accessed after initial storage.

std::size_t	size_bytes {0}
	Size of the instance in bytes.

std::string	study_instance_uid
	Study Instance UID (for grouping migrations)

std::string	series_instance_uid
	Series Instance UID (for grouping migrations)

Detailed Description

Metadata for tracking instance tier location.

Stores information about where an instance is stored and when it was last accessed, used for making migration decisions.

Definition at line 142 of file hsm_types.h.

Member Function Documentation

◆ age()

auto kcenon::pacs::storage::tier_metadata::age ( ) const -> std::chrono::system_clock::duration

inlinenodiscard

Get the age of the instance (time since storage)

Returns: Duration since the instance was stored

Examples: /home/runner/work/pacs_system/pacs_system/include/kcenon/pacs/storage/hsm_types.h.

Definition at line 170 of file hsm_types.h.

                                                                    {
        return std::chrono::system_clock::now() - stored_at;
    }

References stored_at.

Referenced by time_since_access().

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◆ should_migrate()

auto kcenon::pacs::storage::tier_metadata::should_migrate	(	const tier_policy &	policy,
		storage_tier	target_tier ) const -> bool

inlinenodiscard

Check if instance is eligible for migration to a target tier.

Parameters

policy	The tier policy to check against
target_tier	The target tier for migration

Returns: true if instance should be migrated

Examples: /home/runner/work/pacs_system/pacs_system/include/kcenon/pacs/storage/hsm_types.h.

Definition at line 192 of file hsm_types.h.

                                                                               {
        // Can only migrate to a "colder" tier
        if (target_tier <= current_tier) {
            return false;
        }
 
        // Check size threshold
        if (size_bytes < policy.min_migration_size) {
            return false;
        }
 
        auto time_inactive = time_since_access();
 
        // Check if instance has been inactive long enough
        if (current_tier == storage_tier::hot &&
            target_tier == storage_tier::warm) {
            return time_inactive >= policy.hot_to_warm;
        }
 
        if (current_tier == storage_tier::warm &&
            target_tier == storage_tier::cold) {
            return time_inactive >= policy.warm_to_cold;
        }
 
        // Hot directly to cold (must meet both thresholds)
        if (current_tier == storage_tier::hot &&
            target_tier == storage_tier::cold) {
            return time_inactive >= (policy.hot_to_warm + policy.warm_to_cold);
        }
 
        return false;
    }

References kcenon::pacs::storage::cold, current_tier, kcenon::pacs::storage::hot, size_bytes, time_since_access(), and kcenon::pacs::storage::warm.

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◆ time_since_access()

auto kcenon::pacs::storage::tier_metadata::time_since_access ( ) const -> std::chrono::system_clock::duration

inlinenodiscard

Get the time since last access.

Returns: Duration since last access, or age if never accessed

Examples: /home/runner/work/pacs_system/pacs_system/include/kcenon/pacs/storage/hsm_types.h.

Definition at line 178 of file hsm_types.h.

                                         {
        if (last_accessed.has_value()) {
            return std::chrono::system_clock::now() - *last_accessed;
        }
        return age();
    }