parity-util-mem 0.12.0

// Copyright 2020 Parity Technologies
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

//! Crate for parity memory management related utilities.
//! It includes global allocator choice, heap measurement and
//! memory erasure.

#![cfg_attr(not(feature = "std"), no_std)]

#[cfg(not(feature = "std"))]
extern crate alloc;

cfg_if::cfg_if! {
	if #[cfg(all(
		feature = "jemalloc-global",
		not(target_os = "windows"),
		not(target_arch = "wasm32")
	))] {
		/// Global allocator
		#[global_allocator]
		pub static ALLOC: tikv_jemallocator::Jemalloc = tikv_jemallocator::Jemalloc;

		mod memory_stats_jemalloc;
		use memory_stats_jemalloc as memory_stats;
	} else if #[cfg(feature = "dlmalloc-global")] {
		/// Global allocator
		#[global_allocator]
		pub static ALLOC: dlmalloc::GlobalDlmalloc = dlmalloc::GlobalDlmalloc;

		mod memory_stats_noop;
		use memory_stats_noop as memory_stats;
	} else if #[cfg(all(
			feature = "mimalloc-global",
			not(target_arch = "wasm32")
		))] {
		/// Global allocator
		#[global_allocator]
		pub static ALLOC: mimalloc::MiMalloc = mimalloc::MiMalloc;

		mod memory_stats_noop;
		use memory_stats_noop as memory_stats;
	} else {
		// default allocator used
		mod memory_stats_noop;
		use memory_stats_noop as memory_stats;
	}
}

pub mod allocators;

#[cfg(any(
	all(any(target_os = "macos", target_os = "ios"), not(feature = "jemalloc-global"),),
	feature = "estimate-heapsize"
))]
pub mod sizeof;

/// This is a copy of patched crate `malloc_size_of` as a module.
/// We need to have it as an inner module to be able to define our own traits implementation,
/// if at some point the trait become standard enough we could use the right way of doing it
/// by implementing it in our type traits crates. At this time moving this trait to the primitive
/// types level would impact too much of the dependencies to be easily manageable.
#[macro_use]
mod malloc_size;

#[cfg(feature = "ethereum-impls")]
pub mod ethereum_impls;

#[cfg(feature = "primitive-types")]
pub mod primitives_impls;

pub use allocators::MallocSizeOfExt;
pub use malloc_size::{MallocShallowSizeOf, MallocSizeOf, MallocSizeOfOps};

pub use parity_util_mem_derive::*;

/// Heap size of structure.
///
/// Structure can be anything that implements MallocSizeOf.
pub fn malloc_size<T: MallocSizeOf + ?Sized>(t: &T) -> usize {
	MallocSizeOf::size_of(t, &mut allocators::new_malloc_size_ops())
}

/// An error related to the memory stats gathering.
#[derive(Clone, Debug)]
pub struct MemoryStatsError(memory_stats::Error);

#[cfg(feature = "std")]
impl std::fmt::Display for MemoryStatsError {
	fn fmt(&self, fmt: &mut std::fmt::Formatter) -> std::fmt::Result {
		self.0.fmt(fmt)
	}
}

#[cfg(feature = "std")]
impl std::error::Error for MemoryStatsError {}

/// Snapshot of collected memory metrics.
#[non_exhaustive]
#[derive(Debug, Clone)]
pub struct MemoryAllocationSnapshot {
	/// Total resident memory, in bytes.
	pub resident: u64,
	/// Total allocated memory, in bytes.
	pub allocated: u64,
}

/// Accessor to the allocator internals.
#[derive(Clone)]
pub struct MemoryAllocationTracker(self::memory_stats::MemoryAllocationTracker);

impl MemoryAllocationTracker {
	/// Create an instance of an allocation tracker.
	pub fn new() -> Result<Self, MemoryStatsError> {
		self::memory_stats::MemoryAllocationTracker::new()
			.map(MemoryAllocationTracker)
			.map_err(MemoryStatsError)
	}

	/// Create an allocation snapshot.
	pub fn snapshot(&self) -> Result<MemoryAllocationSnapshot, MemoryStatsError> {
		self.0.snapshot().map_err(MemoryStatsError)
	}
}

#[cfg(feature = "std")]
#[cfg(test)]
mod test {
	use super::{malloc_size, MallocSizeOf, MallocSizeOfExt};
	use std::sync::Arc;

	#[test]
	fn test_arc() {
		let val = Arc::new("test".to_string());
		let s = val.malloc_size_of();
		assert!(s > 0);
	}

	#[test]
	fn test_dyn() {
		trait Augmented: MallocSizeOf {}
		impl Augmented for Vec<u8> {}
		let val: Arc<dyn Augmented> = Arc::new(vec![0u8; 1024]);
		assert!(malloc_size(&*val) > 1000);
	}
}