Crate typesize

Typesize

A library to fetch an accurate estimate of the total memory usage of a value.

The goal of this library is to produce the most accurate estimate possible, however without being deeply integrated into the entire ecosystem this cannot be possible. This leads to the real goal being to get “close enough” for getting a sense of memory usage in your program. If one of the TypeSize implementations built-in could be improved, a PR would be greatly appreciated.

An example usage of this library would be to wrap all the types you want to measure recursively in the derive::TypeSize derive macro, and for any types which perform their own heap allocation to manually implement TypeSize while overriding the TypeSize::extra_size method.

MSRV

The Minimum Supported Rust Version is of this crate is 1.65, and it is considered breaking to raise this.

This is without any library support features, as those libraries may require a higher MSRV.

Features

• std: Implements TypeSize for HashMap and HashSet, default enabled.
• details: Adds TypeSize::get_size_details and TypeSize::get_collection_item_count to get field by field breakdowns of struct types.

Library Support

• dashmap: Implements TypeSize for DashMap (Only 5.x, use the typesize feature of dashmap for 6.1+).
• arrayvec: Implements TypeSize for ArrayVec and ArrayString of any size.
• simd_json: Implements TypeSize for OwnedValue and StaticNode, enables halfbrown.
• halfbrown: Implements TypeSize for SizedHashMap, enables hashbrown.
• extract_map_01: Implements TypeSize for extract_map::ExtractMap.
• parking_lot: Implements TypeSize for parking_lot::Mutex and parking_lot::RwLock.
• serde_json: Implements TypeSize for serde_json::Value and serde_json::Map.
• mini_moka: Implements TypeSize for mini_moka::unsync::Cache, and mini_moka::sync::Cache if dashmap is enabled.
• hashbrown: Implements TypeSize for hashbrown::HashMap.
• secrecy: Implements TypeSize for Secret.
• chrono: Implements TypeSize for chrono::DateTime of any chrono::TimeZone.
• nonmax: Implements TypeSize for all nonmax types.
• time: Implements TypeSize for [time::OffsetDateTime].
• url: Implements TypeSize for url::Url.
• bitvec: Implements TypeSize for bitvec::array::BitArray and bitvec::vec::BitVec.
• web-time: Implements TypeSize for web_time::Instant and web_time::SystemTime (on platforms where these aren’t type aliases to std::time types).

Re-exports

• pub use ptr::Ref;
• pub use ptr::RefMut;

Modules

• derive
• ptr
  Wrappers around pointer/reference types to correctly implement TypeSize.

Macros

• if_typesize_details
  Passes through the given tokens if the details feature of typesize is enabled.
• sizeof_impl
  Implements TypeSize for multiple types based on the return value of core::mem::size_of.

Structs

• Field
  A description of a struct or enum field.

Traits

• TypeSize
  A trait to fetch an accurate estimate of the total memory usage of a value.