Crate tikv_jemalloc_ctl 

jemalloc control and introspection.

jemalloc offers a powerful introspection and control interface through the mallctl function. It can be used to tune the allocator, take heap dumps, and retrieve statistics. This crate provides a typed API over that interface.

While mallctl takes a string to specify an operation (e.g. stats.allocated or stats.arenas.15.muzzy_decay_ms), the overhead of repeatedly parsing those strings is not ideal. Fortunately, jemalloc offers the ability to translate the string ahead of time into a “Management Information Base” (MIB) to speed up future lookups.

This crate provides a type for each mallctl operation. Calling $op::{read(), write(x), update(x)} on the type calls mallctl with the string-based API. If the operation will be repeatedly performed, a MIB for the operation can be obtained using $op.mib().

Examples

Repeatedly printing allocation statistics:

use std::thread; use std::time::Duration; use tikv_jemalloc_ctl::{stats, epoch}; #[global_allocator] static ALLOC: tikv_jemallocator::Jemalloc = tikv_jemallocator::Jemalloc; fn main() { loop { // many statistics are cached and only updated when the epoch is advanced. epoch::advance().unwrap(); let allocated = stats::allocated::read().unwrap(); let resident = stats::resident::read().unwrap(); println!("{} bytes allocated/{} bytes resident", allocated, resident); thread::sleep(Duration::from_secs(10)); } }

Doing the same with the MIB-based API:

use std::thread; use std::time::Duration; use tikv_jemalloc_ctl::{stats, epoch}; #[global_allocator] static ALLOC: tikv_jemallocator::Jemalloc = tikv_jemallocator::Jemalloc; fn main() { let e = epoch::mib().unwrap(); let allocated = stats::allocated::mib().unwrap(); let resident = stats::resident::mib().unwrap(); loop { // many statistics are cached and only updated when the epoch is advanced. e.advance().unwrap(); let allocated = allocated.read().unwrap(); let resident = resident.read().unwrap(); println!("{} bytes allocated/{} bytes resident", allocated, resident); thread::sleep(Duration::from_secs(10)); } }

Modules

arenas

Arena operations.

config

jemalloc’s build-time configuration.

opt

jemalloc’s run-time configuration.

profiling

jemalloc’s run-time configuration for profiling-specific settings.

raw

Raw unsafe access to the malloctl API.

stats

Global allocator statistics.

stats_print

Bulk statistics output.

thread

Thread specific operations.

Structs

Error

Errors of the tikv_jemalloc_sys::mallct-family of functions.

Mib

Management Information Base of a non-string value.

MibStr

Management Information Base of a string value.

Name

A Name in the MALLCTL NAMESPACE.

background_thread

State of internal background worker threads.

background_thread_mib

See background_thread.

epoch

jemalloc epoch.

epoch_mib

See epoch.

max_background_threads

Maximum number of background threads that will be created.

max_background_threads_mib

See max_background_threads.

version

jemalloc version string.

version_mib

See version.

Traits

Access

Safe read access to the MALLCTL NAMESPACE.

AsName

Converts a null-terminated byte-string into a Name.

Type Aliases

Result

Result type