blob.h File Reference

Container class for managing multiple scratchpad instances. More...

#include "gridfire/engine/scratchpads/scratchpad_abstract.h"
#include "gridfire/engine/scratchpads/types.h"
#include "gridfire/exceptions/error_scratchpad.h"
#include <unordered_map>
#include <memory>
#include <expected>
#include <unordered_set>

Include dependency graph for blob.h:

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Classes
class	gridfire::engine::scratch::StateBlob
	Container for managing a collection of typed scratchpad instances. More...

Namespaces
namespace	gridfire
namespace	gridfire::engine
namespace	gridfire::engine::scratch
	Scratchpad memory management for computational engines.

Concepts
concept	gridfire::engine::scratch::IsScratchPad
	Concept that constrains types to valid scratchpad implementations.

Detailed Description

Container class for managing multiple scratchpad instances.

This header defines the StateBlob class, which serves as a centralized registry for managing multiple scratchpad instances used by computational engines. It provides type-safe enrollment, retrieval, and cloning of scratchpads using compile-time type checking via C++20 concepts.

Purpose

The StateBlob provides:

• A fixed-size array of scratchpad slots indexed by ScratchPadType
• Type-safe enrollment ensuring one instance per scratchpad type
• Compile-time verified retrieval with optional initialization checks
• Deep cloning of all enrolled scratchpads for parallel execution
• Status tracking for each scratchpad slot

Examples

#include "gridfire/engine/scratchpads/blob.h"
#include "gridfire/engine/scratchpads/engine_graph_scratchpad.h"
 
using namespace gridfire::engine::scratch;
 
// Create a StateBlob and enroll scratchpads
StateBlob blob;
blob.enroll<GraphEngineScratchPad>();
 
// Retrieve a scratchpad (returns std::expected)
auto result = blob.get<GraphEngineScratchPad>();
if (result.has_value()) {
    GraphEngineScratchPad* scratch = result.value();
    scratch->initialize(engine);
}
 
// Retrieve with initialization check
auto checked = blob.get<GraphEngineScratchPad, true>();
if (!checked.has_value()) {
    if (checked.error() == StateBlob::Error::SCRATCHPAD_NOT_INITIALIZED) {
        // Handle uninitialized scratchpad
    }
}
 
// Clone for parallel execution
auto worker_blob = blob.clone_structure();

Thread Safety

The StateBlob class is not thread-safe. Each thread should have its own StateBlob instance. Use clone_structure() to create independent copies for parallel workers. The cloned blob contains deep copies of all enrolled scratchpads.

See also

AbstractScratchPad

ScratchPadType