From 9e9b96a4ad14008284c61b475b0ad783469fb74d Mon Sep 17 00:00:00 2001 From: Christian Grothoff Date: Sun, 9 Feb 2014 18:45:18 +0000 Subject: add api to bandwidth tracker to notify clients about excess bandwidth available --- src/util/bandwidth.c | 136 +++++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 121 insertions(+), 15 deletions(-) (limited to 'src/util') diff --git a/src/util/bandwidth.c b/src/util/bandwidth.c index 09107963c..877164789 100644 --- a/src/util/bandwidth.c +++ b/src/util/bandwidth.c @@ -74,10 +74,8 @@ GNUNET_BANDWIDTH_value_min (struct GNUNET_BANDWIDTH_Value32NBO b1, * @return number of bytes available at bps until deadline */ uint64_t -GNUNET_BANDWIDTH_value_get_available_until (struct GNUNET_BANDWIDTH_Value32NBO - bps, - struct GNUNET_TIME_Relative - deadline) +GNUNET_BANDWIDTH_value_get_available_until (struct GNUNET_BANDWIDTH_Value32NBO bps, + struct GNUNET_TIME_Relative deadline) { uint64_t b; @@ -121,14 +119,79 @@ GNUNET_BANDWIDTH_value_get_delay_for (struct GNUNET_BANDWIDTH_Value32NBO bps, } +/** + * Task run whenever we hit the bandwidth limit for a tracker. + * + * @param cls the `struct GNUNET_BANDWIDTH_Tracker` + * @param tc scheduler context + */ +static void +excess_trigger (void *cls, + const struct GNUNET_SCHEDULER_TaskContext *tc) +{ + struct GNUNET_BANDWIDTH_Tracker *av = cls; + + av->excess_task = GNUNET_SCHEDULER_NO_TASK; + av->excess_cb (av->excess_cb_cls); +} + + +/** + * Recalculate when we might need to call the excess callback. + */ +static void +update_excess (struct GNUNET_BANDWIDTH_Tracker *av) +{ + struct GNUNET_TIME_Relative delay; + struct GNUNET_TIME_Absolute now; + uint64_t delta_time; + uint64_t delta_avail; + int64_t left_bytes; + uint64_t max_carry; + int64_t current_consumption; + + if (NULL == av->excess_cb) + return; /* nothing to do */ + now = GNUNET_TIME_absolute_get (); + delta_time = now.abs_value_us - av->last_update__.abs_value_us; + delta_avail = + (delta_time * ((unsigned long long) av->available_bytes_per_s__) + + 500000LL) / 1000000LL; + current_consumption = av->consumption_since_last_update__ - delta_avail; + /* negative current_consumption means that we have savings */ + max_carry = av->available_bytes_per_s__ * av->max_carry_s__; + if (max_carry < GNUNET_SERVER_MAX_MESSAGE_SIZE) + max_carry = GNUNET_SERVER_MAX_MESSAGE_SIZE; + left_bytes = max_carry + current_consumption; + /* left_bytes now contains the number of bytes needed until + we have more savings than allowed */ + if (left_bytes < 0) + { + /* having excess already */ + delay = GNUNET_TIME_UNIT_ZERO; + } + else + { + delay = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, + left_bytes); + delay = GNUNET_TIME_relative_divide (delay, + av->available_bytes_per_s__); + } + if (GNUNET_SCHEDULER_NO_TASK != av->excess_task) + GNUNET_SCHEDULER_cancel (av->excess_task); + av->excess_task = GNUNET_SCHEDULER_add_delayed (delay, + &excess_trigger, + av); +} + /** * Initialize bandwidth tracker. Note that in addition to the * 'max_carry_s' limit, we also always allow at least - * GNUNET_SERVER_MAX_MESSAGE_SIZE to accumulate. So if the + * #GNUNET_SERVER_MAX_MESSAGE_SIZE to accumulate. So if the * bytes-per-second limit is so small that within 'max_carry_s' not - * even GNUNET_SERVER_MAX_MESSAGE_SIZE is allowed to accumulate, it is - * ignored and replaced by GNUNET_SERVER_MAX_MESSAGE_SIZE (which is in + * even #GNUNET_SERVER_MAX_MESSAGE_SIZE is allowed to accumulate, it is + * ignored and replaced by #GNUNET_SERVER_MAX_MESSAGE_SIZE (which is in * bytes). * * @param av tracker to initialize @@ -137,13 +200,17 @@ GNUNET_BANDWIDTH_value_get_delay_for (struct GNUNET_BANDWIDTH_Value32NBO bps, * @param bytes_per_second_limit initial limit to assume * @param max_carry_s maximum number of seconds unused bandwidth * may accumulate before it expires + * @param excess_cb callback to notify if we have excess bandwidth + * @param excess_cb_cls closure for @a excess_cb */ void -GNUNET_BANDWIDTH_tracker_init (struct GNUNET_BANDWIDTH_Tracker *av, - GNUNET_BANDWIDTH_tracker_update_cb update_cb, - void *update_cb_cls, - struct GNUNET_BANDWIDTH_Value32NBO - bytes_per_second_limit, uint32_t max_carry_s) +GNUNET_BANDWIDTH_tracker_init2 (struct GNUNET_BANDWIDTH_Tracker *av, + GNUNET_BANDWIDTH_TrackerUpdateCallback update_cb, + void *update_cb_cls, + struct GNUNET_BANDWIDTH_Value32NBO bytes_per_second_limit, + uint32_t max_carry_s, + GNUNET_BANDWIDTH_ExcessNotificationCallback excess_cb, + void *excess_cb_cls) { av->update_cb = update_cb; av->update_cb_cls = update_cb_cls; @@ -151,9 +218,45 @@ GNUNET_BANDWIDTH_tracker_init (struct GNUNET_BANDWIDTH_Tracker *av, av->last_update__ = GNUNET_TIME_absolute_get (); av->available_bytes_per_s__ = ntohl (bytes_per_second_limit.value__); av->max_carry_s__ = max_carry_s; + av->excess_cb = excess_cb; + av->excess_cb_cls = excess_cb_cls; LOG (GNUNET_ERROR_TYPE_DEBUG, - "Tracker %p initialized with %u Bps and max carry %u\n", av, - (unsigned int) av->available_bytes_per_s__, (unsigned int) max_carry_s); + "Tracker %p initialized with %u Bps and max carry %u\n", + av, + (unsigned int) av->available_bytes_per_s__, + (unsigned int) max_carry_s); + update_excess (av); +} + + +/** + * Initialize bandwidth tracker. Note that in addition to the + * 'max_carry_s' limit, we also always allow at least + * GNUNET_SERVER_MAX_MESSAGE_SIZE to accumulate. So if the + * bytes-per-second limit is so small that within 'max_carry_s' not + * even GNUNET_SERVER_MAX_MESSAGE_SIZE is allowed to accumulate, it is + * ignored and replaced by GNUNET_SERVER_MAX_MESSAGE_SIZE (which is in + * bytes). + * + * @param av tracker to initialize + * @param update_cb callback to notify a client about the tracker being updated + * @param update_cb_cls cls for the callback + * @param bytes_per_second_limit initial limit to assume + * @param max_carry_s maximum number of seconds unused bandwidth + * may accumulate before it expires + */ +void +GNUNET_BANDWIDTH_tracker_init (struct GNUNET_BANDWIDTH_Tracker *av, + GNUNET_BANDWIDTH_TrackerUpdateCallback update_cb, + void *update_cb_cls, + struct GNUNET_BANDWIDTH_Value32NBO bytes_per_second_limit, + uint32_t max_carry_s) +{ + GNUNET_BANDWIDTH_tracker_init2 (av, update_cb, + update_cb_cls, + bytes_per_second_limit, + max_carry_s, + NULL, NULL); } @@ -230,6 +333,7 @@ GNUNET_BANDWIDTH_tracker_consume (struct GNUNET_BANDWIDTH_Tracker *av, } av->consumption_since_last_update__ = nc; update_tracker (av); + update_excess (av); if (av->consumption_since_last_update__ > 0) { LOG (GNUNET_ERROR_TYPE_DEBUG, @@ -241,6 +345,7 @@ GNUNET_BANDWIDTH_tracker_consume (struct GNUNET_BANDWIDTH_Tracker *av, else { av->consumption_since_last_update__ += size; + update_excess (av); } return GNUNET_NO; } @@ -262,7 +367,7 @@ GNUNET_BANDWIDTH_tracker_get_delay (struct GNUNET_BANDWIDTH_Tracker *av, struct GNUNET_TIME_Relative ret; int64_t bytes_needed; - if (av->available_bytes_per_s__ == 0) + if (0 == av->available_bytes_per_s__) { LOG (GNUNET_ERROR_TYPE_DEBUG, "Tracker %p delay is infinity\n", av); @@ -340,6 +445,7 @@ GNUNET_BANDWIDTH_tracker_update_quota (struct GNUNET_BANDWIDTH_Tracker *av, av->update_cb (av->update_cb_cls); if (old_limit > new_limit) update_tracker (av); /* maximum excess might be less now */ + update_excess (av); } -- cgit v1.2.3