Make queue thresholds and flush size for global scheduler into config options (12b6c7df) · Commits · Benjamin J. Thompson / Tor

src/or/config.c

+22 −0

Original line number	Diff line number	Diff line
		@@ -367,6 +367,9 @@ static config_var_t option_vars_[] = {
		V(ServerDNSSearchDomains, BOOL, "0"),
		V(ServerDNSTestAddresses, CSV,
		"www.google.com,www.mit.edu,www.yahoo.com,www.slashdot.org"),
		V(SchedulerLowWaterMark, MEMUNIT, "16 kB"),
		V(SchedulerHighWaterMark, MEMUNIT, "32 kB"),
		V(SchedulerMaxFlushCells, UINT, "16"),
		V(ShutdownWaitLength, INTERVAL, "30 seconds"),
		V(SocksListenAddress, LINELIST, NULL),
		V(SocksPolicy, LINELIST, NULL),
		@@ -1522,6 +1525,25 @@ options_act(const or_options_t *old_options)
		return -1;
		}

		/* Set up scheduler thresholds */
		if (options->SchedulerLowWaterMark > 0 &&
		options->SchedulerHighWaterMark > options->SchedulerLowWaterMark) {
		scheduler_set_watermarks(options->SchedulerLowWaterMark,
		options->SchedulerHighWaterMark,
		(options->SchedulerMaxFlushCells > 0) ?
		options->SchedulerMaxFlushCells : 16);
		} else {
		if (options->SchedulerLowWaterMark == 0) {
		log_warn(LD_GENERAL, "Bad SchedulerLowWaterMark option");
		}

		if (options->SchedulerHighWaterMark <= options->SchedulerLowWaterMark) {
		log_warn(LD_GENERAL, "Bad SchedulerHighWaterMark option");
		}

		return -1;
		}

		/* Set up accounting */
		if (accounting_parse_options(options, 0)<0) {
		log_warn(LD_CONFIG,"Error in accounting options");

src/or/or.h

+13 −0

Original line number	Diff line number	Diff line
		@@ -4229,6 +4229,19 @@ typedef struct {

		/** Should we send the timestamps that pre-023 hidden services want? */
		int Support022HiddenServices;

		/** Low-water mark for global scheduler - start sending when estimated
		* queued size falls below this threshold.
		*/
		uint32_t SchedulerLowWaterMark;
		/** High-water mark for global scheduler - stop sending when estimated
		* queued size exceeds this threshold.
		*/
		uint32_t SchedulerHighWaterMark;
		/** Flush size for global scheduler - flush this many cells at a time
		* when sending.
		*/
		unsigned int SchedulerMaxFlushCells;
		} or_options_t;

		/** Persistent state for an onion router, as saved to disk. */

src/or/scheduler.c

+29 −9

Original line number	Diff line number	Diff line
		@@ -21,16 +21,20 @@
		#include <event.h>
		#endif

		#define SCHED_Q_LOW_WATER 16384
		#define SCHED_Q_HIGH_WATER (2 * SCHED_Q_LOW_WATER)
		/*
		* Scheduler high/low watermarks
		*/

		static uint32_t sched_q_low_water = 16384;
		static uint32_t sched_q_high_water = 32768;

		/*
		* Maximum cells to flush in a single call to channel_flush_some_cells();
		* setting this low means more calls, but too high and we could overshoot
		* SCHED_Q_HIGH_WATER.
		* sched_q_high_water.
		*/

		#define SCHED_MAX_FLUSH_CELLS 16
		static uint32_t sched_max_flush_cells = 16;

		/*
		* Write scheduling works by keeping track of which channels can
		@@ -343,7 +347,7 @@ scheduler_more_work(void)
		{
		tor_assert(channels_pending);

		return ((scheduler_get_queue_heuristic() < SCHED_Q_LOW_WATER) &&
		return ((scheduler_get_queue_heuristic() < sched_q_low_water) &&
		((smartlist_len(channels_pending) > 0))) ? 1 : 0;
		}

		@@ -387,12 +391,12 @@ scheduler_run, (void))

		log_debug(LD_SCHED, "We have a chance to run the scheduler");

		if (scheduler_get_queue_heuristic() < SCHED_Q_LOW_WATER) {
		if (scheduler_get_queue_heuristic() < sched_q_low_water) {
		n_chans_before = smartlist_len(channels_pending);
		q_len_before = channel_get_global_queue_estimate();
		q_heur_before = scheduler_get_queue_heuristic();

		while (scheduler_get_queue_heuristic() <= SCHED_Q_HIGH_WATER &&
		while (scheduler_get_queue_heuristic() <= sched_q_high_water &&
		smartlist_len(channels_pending) > 0) {
		/* Pop off a channel */
		chan = smartlist_pqueue_pop(channels_pending,
		@@ -410,10 +414,10 @@ scheduler_run, (void))

		flushed = 0;
		while (flushed < n_cells &&
		scheduler_get_queue_heuristic() <= SCHED_Q_HIGH_WATER) {
		scheduler_get_queue_heuristic() <= sched_q_high_water) {
		flushed_this_time =
		channel_flush_some_cells(chan,
		MIN(SCHED_MAX_FLUSH_CELLS,
		MIN(sched_max_flush_cells,
		n_cells - flushed));
		if (flushed_this_time <= 0) break;
		flushed += flushed_this_time;
		@@ -686,3 +690,19 @@ scheduler_update_queue_heuristic(time_t now)
		/* else no update needed, or time went backward */
		}

		/**
		* Set scheduler watermarks and flush size
		*/

		void
		scheduler_set_watermarks(uint32_t lo, uint32_t hi, uint32_t max_flush)
		{
		/* Sanity assertions - caller should ensure these are true */
		tor_assert(lo > 0);
		tor_assert(hi > lo);
		tor_assert(max_flush > 0);

		sched_q_low_water = lo;
		sched_q_high_water = hi;
		sched_max_flush_cells = max_flush;
		}

src/or/scheduler.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -34,6 +34,9 @@ void scheduler_adjust_queue_size(channel_t *chan, char dir, uint64_t adj);
		/* Notify scheduler that a channel's queue position may have changed */
		void scheduler_touch_channel(channel_t *chan);

		/* Adjust the watermarks from config file*/
		void scheduler_set_watermarks(uint32_t lo, uint32_t hi, uint32_t max_flush);

		/* Things only scheduler.c and its test suite should see */

		#ifdef SCHEDULER_PRIVATE_