Commit 5d7b0899 authored by Nick Mathewson's avatar Nick Mathewson
Browse files

Stop making abandoned/successful circuit counts persistent

The C Tor implementation doesn't do this, and Mike says:

   I think it is a reasonable enough assumption that if Tor has
   restarted, this kind data is no longer fresh enough to be
   accurate for this purpose. This is also only 20 circuits here,
   and typical timeouts are now around 1-2 seconds or less.. So a
   restarted client with a timeout that is too low for a new
   internet connection will figure this out pretty quickly. I think
   that is OK.

(from torspec!40)
parent e5cb5de2
......@@ -483,10 +483,6 @@ pub(crate) struct ParetoTimeoutState {
histogram: Vec<(MsecDuration, u16)>,
/// The current timeout estimate: kept for reference.
current_timeout: Option<MsecDuration>,
/// How many abandoned circuits have we seen "recently"
abandoned_circs: usize,
/// How many successful circuits have we seen "recently"
successful_circs: usize,
impl ParetoTimeoutEstimator {
......@@ -508,22 +504,7 @@ impl ParetoTimeoutEstimator {
/// Create a new ParetoTimeoutEstimator based on a loaded
/// ParetoTimeoutState.
pub(crate) fn from_state(state: ParetoTimeoutState) -> Self {
let mut history = History::from_sparse_histogram(state.histogram.into_iter());
// We cap these numbers at the largest number that could be recorded,
// so that we don't run away adding too much if the state file is
// corrupt.
let failed = std::cmp::max(state.abandoned_circs, SUCCESS_HISTORY_DEFAULT_LEN);
let succeeded = std::cmp::max(state.successful_circs, SUCCESS_HISTORY_DEFAULT_LEN);
// We add failures before successes so that they expire first;
// this is biased against throwing away data.
// TODO-SPEC: path-spec.txt doesn't say what order to restore this
// history in.
for _ in 0..failed {
for _ in 0..succeeded {
let history = History::from_sparse_histogram(state.histogram.into_iter());
......@@ -540,8 +521,6 @@ impl ParetoTimeoutEstimator {
version: 1,
histogram: this.history.sparse_histogram().collect(),
current_timeout: Some(cur_timeout),
abandoned_circs: this.history.n_recent_timeouts(),
successful_circs: this.history.success_history.len() - this.history.n_recent_timeouts(),
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment