diff options
Diffstat (limited to 'src/or/circuitbuild.c')
-rw-r--r-- | src/or/circuitbuild.c | 100 |
1 files changed, 53 insertions, 47 deletions
diff --git a/src/or/circuitbuild.c b/src/or/circuitbuild.c index c00f77caf..bfbc144d9 100644 --- a/src/or/circuitbuild.c +++ b/src/or/circuitbuild.c @@ -140,14 +140,14 @@ circuit_build_times_init(circuit_build_times_t *cbt) memset(cbt, 0, sizeof(*cbt)); if (!unit_tests && get_options()->CircuitBuildTimeout) { - cbt->timeout = get_options()->CircuitBuildTimeout; - if (cbt->timeout < BUILD_TIMEOUT_MIN_VALUE) { - log_warn(LD_CIRC, "Config CircuitBuildTimeout too low. Setting to %d", - BUILD_TIMEOUT_MIN_VALUE); - cbt->timeout = BUILD_TIMEOUT_MIN_VALUE; + cbt->timeout_ms = get_options()->CircuitBuildTimeout*1000; + if (cbt->timeout_ms < BUILD_TIMEOUT_MIN_VALUE) { + log_warn(LD_CIRC, "Config CircuitBuildTimeout too low. Setting to %ds", + BUILD_TIMEOUT_MIN_VALUE/1000); + cbt->timeout_ms = BUILD_TIMEOUT_MIN_VALUE; } } else { - cbt->timeout = BUILD_TIMEOUT_INITIAL_VALUE; + cbt->timeout_ms = BUILD_TIMEOUT_INITIAL_VALUE; } } @@ -469,6 +469,8 @@ circuit_build_times_update_alpha(circuit_build_times_t *cbt) * http://en.wikipedia.org/wiki/Pareto_distribution#Generating_a_ * random_sample_from_Pareto_distribution * That's right. I'll cite wikipedia all day long. + * + * Return value is in milliseconds. */ double circuit_build_times_calculate_timeout(circuit_build_times_t *cbt, @@ -501,7 +503,7 @@ circuit_build_times_cdf(circuit_build_times_t *cbt, double x) /** * Generate a synthetic time using our distribution parameters. * - * The return value will be between q_lo and q_hi quantile points + * The return value will be within the [q_lo, q_hi) quantile points * on the CDF. */ build_time_t @@ -512,14 +514,18 @@ circuit_build_times_generate_sample(circuit_build_times_t *cbt, build_time_t ret; double u; + /* Generate between [q_lo, q_hi) */ + q_hi -= 1.0/(INT32_MAX); + tor_assert(q_lo >= 0); tor_assert(q_hi < 1); + tor_assert(q_lo < q_hi); u = q_lo + ((q_hi-q_lo)*r)/(1.0*UINT64_MAX); tor_assert(0 <= u && u < 1.0); /* circuit_build_times_calculate_timeout returns <= INT32_MAX */ - ret = (uint32_t)lround(circuit_build_times_calculate_timeout(cbt, u)); + ret = (build_time_t)lround(circuit_build_times_calculate_timeout(cbt, u)); tor_assert(ret > 0); return ret; } @@ -532,11 +538,11 @@ circuit_build_times_add_timeout_worker(circuit_build_times_t *cbt, build_time_t gentime = circuit_build_times_generate_sample(cbt, quantile_cutoff, MAX_SYNTHETIC_QUANTILE); - if (gentime < (build_time_t)cbt->timeout*1000) { + if (gentime < (build_time_t)lround(cbt->timeout_ms)) { log_warn(LD_CIRC, "Generated a synthetic timeout LESS than the current timeout: " - "%u vs %d using Xm: %d a: %lf, q: %lf", - gentime, cbt->timeout*1000, cbt->Xm, cbt->alpha, quantile_cutoff); + "%ums vs %lfms using Xm: %d a: %lf, q: %lf", + gentime, cbt->timeout_ms, cbt->Xm, cbt->alpha, quantile_cutoff); } else if (gentime > BUILD_TIME_MAX) { gentime = BUILD_TIME_MAX; log_info(LD_CIRC, @@ -556,7 +562,7 @@ circuit_build_times_add_timeout_worker(circuit_build_times_t *cbt, */ void circuit_build_times_initial_alpha(circuit_build_times_t *cbt, - double quantile, build_time_t timeout) + double quantile, double timeout_ms) { // Q(u) = Xm/((1-u)^(1/a)) // Q(0.8) = Xm/((1-0.8))^(1/a)) = CircBuildTimeout @@ -566,7 +572,7 @@ circuit_build_times_initial_alpha(circuit_build_times_t *cbt, // -ln(1-0.8)/(ln(CircBuildTimeout)-ln(Xm))=a tor_assert(quantile > 0); tor_assert(cbt->Xm > 0); - cbt->alpha = ln(1.0-quantile)/(ln(cbt->Xm)-ln(timeout)); + cbt->alpha = ln(1.0-quantile)/(ln(cbt->Xm)-ln(timeout_ms)); tor_assert(cbt->alpha > 0); } @@ -585,9 +591,9 @@ circuit_build_times_count_pretimeouts(circuit_build_times_t *cbt) (cbt->pre_timeouts+cbt->total_build_times); cbt->Xm = circuit_build_times_min(cbt); tor_assert(cbt->Xm > 0); - // Use current timeout to get an estimate on alpha + /* Use current timeout to get an estimate on alpha */ circuit_build_times_initial_alpha(cbt, timeout_quantile, - cbt->timeout*1000); + cbt->timeout_ms); while (cbt->pre_timeouts-- != 0) { circuit_build_times_add_timeout_worker(cbt, timeout_quantile); } @@ -629,14 +635,14 @@ circuit_build_times_network_is_live(circuit_build_times_t *cbt) /** * Returns true if the network showed some sign of liveness - * in the past NETWORK_LIVE_MULTIPLIER*cbt->timeout seconds. + * in the past NETWORK_LIVE_MULTIPLIER*cbt->timeout_ms/1000 seconds. */ int circuit_build_times_is_network_live(circuit_build_times_t *cbt) { time_t now = approx_time(); if (now - cbt->network_last_live > - (cbt->timeout*NETWORK_LIVE_MULTIPLIER)) { + (cbt->timeout_ms*NETWORK_LIVE_MULTIPLIER/1000.0)) { log_info(LD_CIRC, "Network is no longer live. Dead for %ld seconds.", (long int)(now - cbt->network_last_live)); return 0; @@ -658,7 +664,6 @@ circuit_build_times_check_too_many_timeouts(circuit_build_times_t *cbt) { double timeout_rate=0; build_time_t Xm = BUILD_TIME_MAX; - double timeout; int i; if ((cbt->pre_timeouts + cbt->total_build_times) < RECENT_CIRCUITS) { @@ -666,13 +671,17 @@ circuit_build_times_check_too_many_timeouts(circuit_build_times_t *cbt) } /* Get timeout rate and Xm for recent circs */ + /* XXX: Hrmm, if the switch is a hard switch, then 4 times + * will be from the previous network and will give a really low Xm + * and thus a really low alpha and thus a high timeout */ for (i = (cbt->build_times_idx - RECENT_CIRCUITS) % NCIRCUITS_TO_OBSERVE; i != cbt->build_times_idx; i = (i + 1) % NCIRCUITS_TO_OBSERVE) { if (cbt->circuit_build_times[i] && cbt->circuit_build_times[i] < Xm) { Xm = cbt->circuit_build_times[i]; } - if (cbt->circuit_build_times[i] > (build_time_t)cbt->timeout*1000) { + if (cbt->circuit_build_times[i]+1 >= + (build_time_t)lround(cbt->timeout_ms)) { timeout_rate++; } } @@ -690,14 +699,14 @@ circuit_build_times_check_too_many_timeouts(circuit_build_times_t *cbt) "Resetting timeouts after %d pretimouts and %d buildtimes", cbt->pre_timeouts, cbt->total_build_times); - if (Xm >= (build_time_t)cbt->timeout*1000) { + if (Xm >= (build_time_t)lround(cbt->timeout_ms)) { Xm = circuit_build_times_min(cbt); - if (Xm >= (build_time_t)cbt->timeout*1000) { + if (Xm >= (build_time_t)lround(cbt->timeout_ms)) { /* No circuits have completed */ - cbt->timeout *= 2; + cbt->timeout_ms *= 2; log_warn(LD_CIRC, - "Adjusting CircuitBuildTimeout to %d in the hopes that " - "some connections will succeed", cbt->timeout); + "Adjusting CircuitBuildTimeout to %lds in the hopes that " + "some connections will succeed", lround(cbt->timeout_ms/1000)); goto reset; } } @@ -705,23 +714,23 @@ circuit_build_times_check_too_many_timeouts(circuit_build_times_t *cbt) cbt->Xm = Xm; circuit_build_times_initial_alpha(cbt, 1.0-timeout_rate, - cbt->timeout*1000); + cbt->timeout_ms); - timeout = circuit_build_times_calculate_timeout(cbt, - BUILDTIMEOUT_QUANTILE_CUTOFF); /* timeout is INT32_MAX at most */ - cbt->timeout = (uint32_t)lround(timeout/1000.0); + cbt->timeout_ms = circuit_build_times_calculate_timeout(cbt, + BUILDTIMEOUT_QUANTILE_CUTOFF); - if (cbt->timeout < BUILD_TIMEOUT_MIN_VALUE) { - log_warn(LD_CIRC, "Reset buildtimeout to low value %lf. Setting to %d", - timeout, BUILD_TIMEOUT_MIN_VALUE); - cbt->timeout = BUILD_TIMEOUT_MIN_VALUE; + if (cbt->timeout_ms < BUILD_TIMEOUT_MIN_VALUE) { + log_warn(LD_CIRC, "Reset buildtimeout to low value %lfms. Setting to %dms", + cbt->timeout_ms, BUILD_TIMEOUT_MIN_VALUE); + cbt->timeout_ms = BUILD_TIMEOUT_MIN_VALUE; } log_notice(LD_CIRC, - "Reset circuit build timeout to %d (%lf, Xm: %d, a: %lf) based " - "on %d recent circuit times", cbt->timeout, timeout, cbt->Xm, - cbt->alpha, RECENT_CIRCUITS); + "Reset circuit build timeout to %lds (%lfms, Xm: %d, a: %lf) " + "based on timeout rate of %lf on %d recent circuit times", + lround(cbt->timeout_ms/1000), cbt->timeout_ms, cbt->Xm, + cbt->alpha, timeout_rate, RECENT_CIRCUITS); reset: @@ -764,8 +773,6 @@ circuit_build_times_add_timeout(circuit_build_times_t *cbt) void circuit_build_times_set_timeout(circuit_build_times_t *cbt) { - double timeout; - if (cbt->total_build_times < MIN_CIRCUITS_TO_OBSERVE) { log_info(LD_CIRC, "Not enough circuits yet to calculate a new build timeout." @@ -776,23 +783,22 @@ circuit_build_times_set_timeout(circuit_build_times_t *cbt) circuit_build_times_count_pretimeouts(cbt); circuit_build_times_update_alpha(cbt); - timeout = circuit_build_times_calculate_timeout(cbt, + /* timeout is INT32_MAX at most */ + cbt->timeout_ms = circuit_build_times_calculate_timeout(cbt, BUILDTIMEOUT_QUANTILE_CUTOFF); cbt->have_computed_timeout = 1; - /* timeout is INT32_MAX at most */ - cbt->timeout = (uint32_t)lround(timeout/1000.0); - if (cbt->timeout < BUILD_TIMEOUT_MIN_VALUE) { - log_warn(LD_CIRC, "Set buildtimeout to low value %lf. Setting to %d", - timeout, BUILD_TIMEOUT_MIN_VALUE); - cbt->timeout = BUILD_TIMEOUT_MIN_VALUE; + if (cbt->timeout_ms < BUILD_TIMEOUT_MIN_VALUE) { + log_warn(LD_CIRC, "Set buildtimeout to low value %lfms. Setting to %dms", + cbt->timeout_ms, BUILD_TIMEOUT_MIN_VALUE); + cbt->timeout_ms = BUILD_TIMEOUT_MIN_VALUE; } log_info(LD_CIRC, - "Set circuit build timeout to %d (%lf, Xm: %d, a: %lf) based on " - "%d circuit times", cbt->timeout, timeout, cbt->Xm, cbt->alpha, - cbt->total_build_times); + "Set circuit build timeout to %lds (%lfms, Xm: %d, a: %lf) " + "based on %d circuit times", lround(cbt->timeout_ms/1000), + cbt->timeout_ms, cbt->Xm, cbt->alpha, cbt->total_build_times); } |