Expand description
Rust Bindings for the Hwloc library
This library is a rust binding to the hwloc C library, which provides a portable abstraction of the hierarchical topology of modern architectures, including NUMA memory nodes, sockets, shared caches, cores and simultaneous multithreading.
§Usage
First, add the following to your Cargo.toml
:
[dependencies]
hwloc = "0.3.0"
Next, add this to your crate root:
extern crate hwloc;
Here is a quick example which walks the Topology
and prints it out:
extern crate hwloc;
use hwloc::Topology;
fn main() {
let topo = Topology::new();
for i in 0..topo.depth() {
println!("*** Objects at level {}", i);
for (idx, object) in topo.objects_at_depth(i).iter().enumerate() {
println!("{}: {}", idx, object);
}
}
}
You can also look at more examples, if you want to run them check out the next section below.
§Running Examples
The library ships with examples, and to run them you need to clone the repository
and then run them through cargo run --example=
.
$ git clone https://github.com/daschl/hwloc-rs.git
$ cd hwloc-rs
To run an example (which will download the dependencies and build it) you can
use cargo run -example=
:
$ cargo run --example=walk_tree
Compiling libc v0.2.3
...
Compiling hwloc v0.2.0 (file:///vagrant/hwloc-rs)
Running `target/debug/examples/walk_tree`
*** Printing overall tree
Machine (490MB): #0
Socket (): #0
L2d (6144KB): #4294967295
L1d (32KB): #4294967295
Core (): #0
PU (): #0
L1d (32KB): #4294967295
Core (): #1
PU (): #1
§License
This project uses the MIT license, please see the LICENSE file for more information.
Structs§
- Bitmap
- A generic bitmap, understood by hwloc.
- CpuBind
Flags - Process/Thread binding flags.
- MemBind
Policy - Topology
- Topology
CpuBind Support - Flags describing actual PU binding support for this topology.
- Topology
Discovery Support - Topology
MemBind Support - Flags describing actual memory binding support for this topology.
- Topology
Object - Topology
Object Memory - Topology
Support
Enums§
- CpuBind
Error - Object
Type - Represents the type of a topology object.
- Topology
Flag - Type
Depth Error
Constants§
- CPUBIND_
NO_ MEMBIND - Avoid any effect on memory binding.
- CPUBIND_
PROCESS - Bind all threads of the current (possibly) multithreaded process.
- CPUBIND_
STRICT - Request for strict binding from the OS.
- CPUBIND_
THREAD - Bind current thread of current process.
- MEMBIND_
BIND - Allocate memory on the specified nodes.
- MEMBIND_
DEFAULT - Reset the memory allocation policy to the system default. Depending on the operating system, this may correspond to MEMBIND_FIRSTTOUCH (Linux), or MEMBIND_BIND (AIX, HP-UX, OSF, Solaris, Windows).
- MEMBIND_
FIRSTTOUCH - Allocate memory but do not immediately bind it to a specific locality. Instead, each page in the allocation is bound only when it is first touched. Pages are individually bound to the local NUMA node of the first thread that touches it. If there is not enough memory on the node, allocation may be done in the specified cpuset before allocating on other nodes.
- MEMBIND_
INTERLEAVE - Allocate memory on the given nodes in an interleaved / round-robin manner. The precise layout of the memory across multiple NUMA nodes is OS/system specific. Interleaving can be useful when threads distributed across the specified NUMA nodes will all be accessing the whole memory range concurrently, since the interleave will then balance the memory references.
- MEMBIND_
MIXED - Returned by get_membind() functions when multiple threads or parts of a memory area have differing memory binding policies.
- MEMBIND_
NEXTTOUCH - For each page bound with this policy, by next time it is touched (and next time only), it is moved from its current location to the local NUMA node of the thread where the memory reference occurred (if it needs to be moved at all).
- MEMBIND_
REPLICATE - Replicate memory on the given nodes; reads from this memory will attempt to be serviced from the NUMA node local to the reading thread. Replicating can be useful when multiple threads from the specified NUMA nodes will be sharing the same read-only data.