Struct RateLimitedBackend 

pub struct RateLimitedBackend { /* private fields */ }

Token-bucket rate limiter wrapping any BlockBackend.

tower::Layer-shaped (without the actual tower dependency — the trait surface here is sync, not request/response): construct via RateLimitedBackend::new with a wrapped backend and a RateLimit budget. Every read_at / write_at calls acquire(buf.len()) first; if the bucket is empty the call blocks (std::thread::sleep) until enough tokens replenish.

Per 14 § 4.1 and the D7-adjacent rate-limiter requirement: bound aggregate throughput within ±5 % of the configured rate. The bucket is refilled continuously based on wall-clock elapsed time since the last drain, which gives a smooth ±n % envelope at any rate.

Implementations

impl RateLimitedBackend

pub fn new(inner: Arc<dyn BlockBackend>, config: RateLimit) -> Self

Wrap inner with a rate-limit gate. inner is held by Arc so the same backend can sit behind several rate-limit slices.

Trait Implementations

impl BlockBackend for RateLimitedBackend

fn size_bytes(&self) -> u64

Total size of the backing storage in bytes.

fn read_at(&self, byte_offset: u64, buf: &mut [u8]) -> Result<()>

Read buf.len() bytes starting at byte_offset.

fn write_at(&self, byte_offset: u64, buf: &[u8]) -> Result<()>

Write buf.len() bytes starting at byte_offset.

fn flush(&self) -> Result<()>

Synchronous flush (fsync).

fn read_only(&self) -> bool

true if the backing storage is opened read-only.

impl Debug for RateLimitedBackend

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.