commit fe5764012a05e5d9382e1a59d015ff6ca0bd804b Author: Mike Perry <mikeperry-git@torproject.org> Date: Wed May 16 06:42:41 2018 +0000 Bug 26121: Improve BUILDTIMEOUT_SET accuracy. We were miscounting the total number of circuits for the TIMEOUT_RATE and CLOSE_RATE fields of this event. --- changes/bug26121 | 6 ++++++ src/or/circuitstats.c | 15 +++++++++++---- 2 files changed, 17 insertions(+), 4 deletions(-) diff --git a/changes/bug26121 b/changes/bug26121 new file mode 100644 index 000000000..5f734dd56 --- /dev/null +++ b/changes/bug26121 @@ -0,0 +1,6 @@ + o Minor bugfixes (controller): + - Improve accuracy of the BUILDTIMEOUT_SET control port event's + TIMEOUT_RATE and CLOSE_RATE fields. (We were previously miscounting + the total number of circuits for these field values.) Fixes bug + 26121; bugfix on 0.3.3.1-alpha. + diff --git a/src/or/circuitstats.c b/src/or/circuitstats.c index f87bbd822..f06c2e5e3 100644 --- a/src/or/circuitstats.c +++ b/src/or/circuitstats.c @@ -1908,13 +1908,20 @@ cbt_control_event_buildtimeout_set(const circuit_build_times_t *cbt, /* The timeout rate is the ratio of the timeout count over * the total number of circuits attempted. The total number of - * circuits is (timeouts+succeeded+closed), since a circuit can - * either timeout, close, or succeed. We cast the denominator + * circuits is (timeouts+succeeded), since every circuit + * either succeeds, or times out. "Closed" circuits are + * MEASURE_TIMEOUT circuits whose measurement period expired. + * All MEASURE_TIMEOUT circuits are counted in the timeouts stat + * before transitioning to MEASURE_TIMEOUT (in + * circuit_build_times_mark_circ_as_measurement_only()). + * MEASURE_TIMEOUT circuits that succeed are *not* counted as + * "succeeded". See circuit_build_times_handle_completed_hop(). + * + * We cast the denominator * to promote it to double before the addition, to avoid int32 * overflow. */ const double total_circuits = - ((double)cbt->num_circ_timeouts) + cbt->num_circ_succeeded - + cbt->num_circ_closed; + ((double)cbt->num_circ_timeouts) + cbt->num_circ_succeeded; if (total_circuits >= 1.0) { timeout_rate = cbt->num_circ_timeouts / total_circuits; close_rate = cbt->num_circ_closed / total_circuits;