commit 125df07d609933a7974f362706b126a4bf339788 Author: Mike Perry mikeperry-git@torproject.org Date: Wed Dec 6 23:56:03 2017 +0000
Report close and timeout rates since uptime, not based on data.
Bug #23114 was harder to see because we were just reporting our math, rather than reporting behavior. --- src/or/circuitstats.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++++-- src/or/circuitstats.h | 10 ++++++++ 2 files changed, 77 insertions(+), 2 deletions(-)
diff --git a/src/or/circuitstats.c b/src/or/circuitstats.c index 0620e045d..afb37771f 100644 --- a/src/or/circuitstats.c +++ b/src/or/circuitstats.c @@ -45,6 +45,7 @@ static void cbt_control_event_buildtimeout_set( const circuit_build_times_t *cbt, buildtimeout_set_event_t type); +static void circuit_build_times_scale_circ_counts(circuit_build_times_t *cbt);
#define CBT_BIN_TO_MS(bin) ((bin)*CBT_BIN_WIDTH + (CBT_BIN_WIDTH/2))
@@ -537,6 +538,11 @@ circuit_build_times_reset(circuit_build_times_t *cbt) cbt->total_build_times = 0; cbt->build_times_idx = 0; cbt->have_computed_timeout = 0; + + // Reset timeout and close counts + cbt->num_circ_succeeded = 0; + cbt->num_circ_closed = 0; + cbt->num_circ_timeouts = 0; }
/** @@ -1404,6 +1410,24 @@ circuit_build_times_network_is_live(circuit_build_times_t *cbt) }
/** + * Non-destructively scale all of our circuit success, timeout, and close + * counts down by a factor of two. Scaling in this way preserves the + * ratios between succeeded vs timed out vs closed circuits, so that + * our statistics don't change when we scale. + * + * This is used only in the rare event that we build more than + * INT32_MAX circuits. Since the num_circ_* variables are + * uint32_t, we won't even be close to overflowing them. + */ +void +circuit_build_times_scale_circ_counts(circuit_build_times_t *cbt) +{ + cbt->num_circ_succeeded /= 2; + cbt->num_circ_timeouts /= 2; + cbt->num_circ_closed /= 2; +} + +/** * Called to indicate that we "completed" a circuit. Because this circuit * succeeded, it doesn't count as a timeout-after-the-first-hop. * @@ -1419,6 +1443,14 @@ circuit_build_times_network_is_live(circuit_build_times_t *cbt) void circuit_build_times_network_circ_success(circuit_build_times_t *cbt) { + // Count circuit success + cbt->num_circ_succeeded++; + + // If we're going to wrap int32, scale everything + if (cbt->num_circ_succeeded >= INT32_MAX) { + circuit_build_times_scale_circ_counts(cbt); + } + /* Check for NULLness because we might not be using adaptive timeouts */ if (cbt->liveness.timeouts_after_firsthop && cbt->liveness.num_recent_circs > 0) { @@ -1441,6 +1473,14 @@ static void circuit_build_times_network_timeout(circuit_build_times_t *cbt, int did_onehop) { + // Count circuit timeout + cbt->num_circ_timeouts++; + + // If we're going to wrap int32, scale everything + if (cbt->num_circ_timeouts >= INT32_MAX) { + circuit_build_times_scale_circ_counts(cbt); + } + /* Check for NULLness because we might not be using adaptive timeouts */ if (cbt->liveness.timeouts_after_firsthop && cbt->liveness.num_recent_circs > 0) { @@ -1466,6 +1506,15 @@ circuit_build_times_network_close(circuit_build_times_t *cbt, int did_onehop, time_t start_time) { time_t now = time(NULL); + + // Count circuit close + cbt->num_circ_closed++; + + // If we're going to wrap int32, scale everything + if (cbt->num_circ_closed >= INT32_MAX) { + circuit_build_times_scale_circ_counts(cbt); + } + /* * Check if this is a timeout that was for a circuit that spent its * entire existence during a time where we have had no network activity. @@ -1820,6 +1869,8 @@ cbt_control_event_buildtimeout_set(const circuit_build_times_t *cbt, { char *args = NULL; double qnt; + double timeout_rate = 0.0; + double close_rate = 0.0;
switch (type) { case BUILDTIMEOUT_SET_EVENT_RESET: @@ -1834,15 +1885,29 @@ cbt_control_event_buildtimeout_set(const circuit_build_times_t *cbt, break; }
+ /* 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 + * 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; + if (total_circuits >= 1.0) { + timeout_rate = cbt->num_circ_timeouts / total_circuits; + close_rate = cbt->num_circ_closed / total_circuits; + } + tor_asprintf(&args, "TOTAL_TIMES=%lu " "TIMEOUT_MS=%lu XM=%lu ALPHA=%f CUTOFF_QUANTILE=%f " "TIMEOUT_RATE=%f CLOSE_MS=%lu CLOSE_RATE=%f", (unsigned long)cbt->total_build_times, (unsigned long)cbt->timeout_ms, (unsigned long)cbt->Xm, cbt->alpha, qnt, - circuit_build_times_timeout_rate(cbt), + timeout_rate, (unsigned long)cbt->close_ms, - circuit_build_times_close_rate(cbt)); + close_rate);
control_event_buildtimeout_set(type, args);
diff --git a/src/or/circuitstats.h b/src/or/circuitstats.h index 7fc65fc8d..86116cb7f 100644 --- a/src/or/circuitstats.h +++ b/src/or/circuitstats.h @@ -96,6 +96,16 @@ struct circuit_build_times_s { double timeout_ms; /** How long we wait before actually closing the circuit. */ double close_ms; + /** Total succeeded counts. Old measurements may be scaled downward if + * we've seen a lot of circuits. */ + uint32_t num_circ_succeeded; + /** Total timeout counts. Old measurements may be scaled downward if + * we've seen a lot of circuits. */ + uint32_t num_circ_timeouts; + /** Total closed counts. Old measurements may be scaled downward if + * we've seen a lot of circuits.*/ + uint32_t num_circ_closed; + }; #endif /* defined(CIRCUITSTATS_PRIVATE) */