commit de373736ee74a300f68e1355e0cbeed812ca5d80 Author: Nick Mathewson nickm@torproject.org Date: Fri Aug 27 11:04:22 2021 -0400

Describe reload behavior of path-spec data. --- path-spec.txt | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/path-spec.txt b/path-spec.txt index f257e86..0243260 100644 --- a/path-spec.txt +++ b/path-spec.txt @@ -423,9 +423,9 @@ of their choices. or network change (see section 2.4.5 below).

Timeouts are stored on disk in a histogram of 10ms bin width, the same - width used to calculate the Xm value above. This histogram must be shuffled - after being read from disk, to preserve a proper expiration of old values - after restart. + width used to calculate the Xm value above. The timeouts recorded in the + histogram must be shuffled after being read from disk, to preserve a + proper expiration of old values after restart.

Thus, some build time resolution is lost during restart. Implementations may choose a different persistence mechanism than this histogram, but be aware @@ -534,6 +534,13 @@ of their choices. If the timeout was already at least `cbtinitialtimeout`, the client doubles the timeout.

+ The records here (of how many circuits succeeded or failed among the most + recent 'cbrrecentcount') are also stored as persistent state. On reload, + the history here is reconstructed from the counts by placing successes and + failures in an arbitrary order. (The C Tor implementation shuffles them, + whereas Arti always places failures before successes so that they expire + sooner.) + 2.4.6. Consensus parameters governing behavior

Clients that implement circuit build timeout learning should obey the