memory_resource.h File Reference

PMR adapter that lets standard pmr-aware containers allocate through vlink::MemoryPool. More...

#include <memory>

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Namespaces
	vlink
	vlink::MemoryResource
	Fallback shim when <memory_resource> is unavailable.

Functions
template<typename T , typename... Args>
std::shared_ptr< T >	vlink::MemoryResource::make_shared (Args &&... args)
	Fallback make_shared forwarding to std::make_shared. More...
template<typename T , typename... Args>
std::unique_ptr< T >	vlink::MemoryResource::make_unique (Args &&... args)
	Fallback make_unique forwarding to std::make_unique. More...

Detailed Description

PMR adapter that lets standard pmr-aware containers allocate through vlink::MemoryPool.

vlink::MemoryResource derives from std::pmr::memory_resource and forwards each request onto an owned (or shared) vlink::MemoryPool. This bridges the standard polymorphic allocator machinery with VLink's tiered pool.

PMR vs VLink resources

Aspect	std::pmr::new_delete_resource	vlink::MemoryResource
Backing allocator	global operator new / delete	vlink::MemoryPool (per-tier free lists)
Allocation footprint	unpredictable per-call	bounded per-tier; pooled
Concurrent allocs	global allocator scaling	per-tier locking, low contention
Bypass mode	not applicable	empty tier list yields pass-through
Maintenance	not applicable	trim releases idle chunks

Lifetime

• MemoryResource(), MemoryResource(int) and MemoryResource(const Config&) each heap-allocate a private MemoryPool and own it for the lifetime of the resource.
• MemoryResource::global_instance returns a process-wide singleton that wraps MemoryPool::global_instance; the resource is not deleted by the destructor.

Example

// Shared process-wide resource.
std::pmr::vector<int> v(&vlink::MemoryResource::global_instance());
v.reserve(1024);
 
// Private level-3 pyramid:
vlink::MemoryResource res(3);
std::pmr::polymorphic_allocator<char> alloc(&res);
std::pmr::string s(alloc);
 
// Private resource with a custom tier list and full-quota preallocation.
vlink::MemoryPool::Config cfg;
cfg.tiers    = {{64, 16}, {1024, 4}};
cfg.prealloc = true;
vlink::MemoryResource custom(cfg);
std::pmr::vector<double> w(&custom);

Note

do_allocate throws std::bad_alloc when the underlying pool returns nullptr, satisfying the pmr contract. Equality is identity over the bound MemoryPool object.