commit 1c0c0022d8199a9b998a0c4e13a85a382abf7fb0 Author: Andrea Shepard <andrea@torproject.org> Date: Thu Jun 30 10:26:13 2016 +0000 Compute thresholds for OOS from ConnLimit_ when setting options --- src/or/config.c | 26 ++++++++++++++++++++++++++ src/or/or.h | 4 ++++ 2 files changed, 30 insertions(+) diff --git a/src/or/config.c b/src/or/config.c index 3fab3b3..33c80e5 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -1334,6 +1334,32 @@ options_act_reversible(const or_options_t *old_options, char **msg) connection_mark_for_close(conn); } }); + + if (set_conn_limit) { + /* + * If we adjusted the conn limit, recompute the OOS threshold too + * + * How many possible sockets to keep in reserve? If we have lots of + * possible sockets, keep this below a limit and set ConnLimit_high_thresh + * very close to ConnLimit_, but if ConnLimit_ is low, shrink it in + * proportion. + * + * Somewhat arbitrarily, set socks_in_reserve to 5% of ConnLimit_, but + * cap it at 64. + */ + int socks_in_reserve = options->ConnLimit_ / 20; + if (socks_in_reserve > 64) socks_in_reserve = 64; + + options->ConnLimit_high_thresh = options->ConnLimit_ - socks_in_reserve; + options->ConnLimit_low_thresh = (options->ConnLimit_ / 4) * 3; + log_info(LD_GENERAL, + "Recomputed OOS thresholds: ConnLimit %d, ConnLimit_ %d, " + "ConnLimit_high_thresh %d, ConnLimit_low_thresh %d", + options->ConnLimit, options->ConnLimit_, + options->ConnLimit_high_thresh, + options->ConnLimit_low_thresh); + } + goto done; rollback: diff --git a/src/or/or.h b/src/or/or.h index 1bac43c..262085e 100644 --- a/src/or/or.h +++ b/src/or/or.h @@ -3699,6 +3699,10 @@ typedef struct { int ConnLimit; /**< Demanded minimum number of simultaneous connections. */ int ConnLimit_; /**< Maximum allowed number of simultaneous connections. */ + int ConnLimit_high_thresh; /**< start trying to lower socket usage if we + * have this many. */ + int ConnLimit_low_thresh; /**< try to get down to here after socket + * exhaustion. */ int RunAsDaemon; /**< If true, run in the background. (Unix only) */ int FascistFirewall; /**< Whether to prefer ORs reachable on open ports. */ smartlist_t *FirewallPorts; /**< Which ports our firewall allows