2 This file is part of GNUnet.
3 (C) 2011 Christian Grothoff (and other contributing authors)
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6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
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12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
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17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file ats/gnunet-service-ats_normalization.c
23 * @brief ats service address: management of ATS properties and preferences normalization
24 * @author Matthias Wachs
25 * @author Christian Grothoff
28 #include "gnunet_ats_service.h"
29 #include "gnunet-service-ats_addresses.h"
30 #include "gnunet-service-ats_normalization.h"
32 #define LOG(kind,...) GNUNET_log_from (kind, "ats-normalization",__VA_ARGS__)
37 struct PreferenceClient
42 struct PreferenceClient *prev;
48 struct PreferenceClient *next;
56 * Total preference for this peer
58 double f_abs_sum[GNUNET_ATS_PreferenceCount];
61 * List of peer preferences for this client
67 struct PreferencePeer *p_head;
72 struct PreferencePeer *p_tail;
83 struct PreferencePeer *next;
88 struct PreferencePeer *prev;
93 struct PreferenceClient *client;
98 struct GNUNET_PeerIdentity id;
101 * Absolute preference values
103 double f_abs[GNUNET_ATS_PreferenceCount];
106 * Relative preference values
108 double f_rel[GNUNET_ATS_PreferenceCount];
110 struct GNUNET_TIME_Absolute next_aging[GNUNET_ATS_PreferenceCount];
114 * Relative preferences for a peer
119 * Relative preference values
121 double f_rel[GNUNET_ATS_PreferenceCount];
126 struct GNUNET_PeerIdentity id;
130 * Callback to call on changing preference values
132 static GAS_Normalization_preference_changed_cb pref_changed_cb;
135 * Closure for callback to call on changing preference values
137 static void *pref_changed_cb_cls;
140 * Callback to call on changing property values
142 GAS_Normalization_property_changed_cb prop_ch_cb;
145 * Closure for callback to call on changing property values
147 void *prop_ch_cb_cls;
150 * Hashmap to store peer information for preference normalization
152 static struct GNUNET_CONTAINER_MultiHashMap *preference_peers;
155 * Hashmap to store peer information for property normalization
157 static struct GNUNET_CONTAINER_MultiHashMap *property_peers;
160 * Clients in DLL: head
162 static struct PreferenceClient *pc_head;
165 * Clients in DLL: tail
167 static struct PreferenceClient *pc_tail;
172 static struct PeerRelative defvalues;
174 static GNUNET_SCHEDULER_TaskIdentifier aging_task;
177 * Application Preference Normalization
183 * @param kind the kind
184 * @return the new relative preference
187 update_peers (struct GNUNET_PeerIdentity *id,
188 enum GNUNET_ATS_PreferenceKind kind)
190 struct PreferenceClient *c_cur;
191 struct PreferencePeer *p_cur;
192 struct PeerRelative *rp;
200 /* For all clients */
201 for (c_cur = pc_head; NULL != c_cur; c_cur = c_cur->next)
203 /* Find peer with id */
204 for (p_cur = c_cur->p_head; NULL != p_cur; p_cur = p_cur->next)
206 if (0 == memcmp (id, &p_cur->id, sizeof(struct GNUNET_PeerIdentity)))
211 /* Found peer with id */
212 f_rel_total += p_cur->f_rel[kind];
218 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
219 "%u clients have a total relative preference for peer `%s''s `%s' of %.3f\n",
220 count, GNUNET_i2s (id), GNUNET_ATS_print_preference_type (kind),
223 != (rp = GNUNET_CONTAINER_multihashmap_get (preference_peers,
226 backup = rp->f_rel[kind];
229 rp->f_rel[kind] = f_rel_total / count;
233 rp->f_rel[kind] = DEFAULT_REL_PREFERENCE;
238 return DEFAULT_REL_PREFERENCE;
241 if ((backup != rp->f_rel[kind]) && (NULL != pref_changed_cb))
243 pref_changed_cb (pref_changed_cb_cls, &rp->id, kind, rp->f_rel[kind]);
246 return rp->f_rel[kind];
250 * Recalculate preference for a specific ATS property
252 * @param c the preference client
254 * @param kind the preference kind
258 recalculate_rel_preferences (struct PreferenceClient *c,
259 struct PreferencePeer *p, enum GNUNET_ATS_PreferenceKind kind)
261 struct PreferencePeer *p_cur;
262 struct PeerRelative *rp;
267 /* For this client: sum preferences to total preference */
268 c->f_abs_sum[kind] = 0;
269 for (p_cur = c->p_head; NULL != p_cur; p_cur = p_cur->next)
270 c->f_abs_sum[kind] += p_cur->f_abs[kind];
271 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
272 "Client %p has total preference for %s of %.3f\n", c->client,
273 GNUNET_ATS_print_preference_type (kind), c->f_abs_sum[kind]);
275 ret = DEFAULT_REL_PREFERENCE;
276 /* For all peers: calculate relative preference */
277 for (p_cur = c->p_head; NULL != p_cur; p_cur = p_cur->next)
279 /* Calculate relative preference for specific kind */
280 backup = p_cur->f_rel[kind];
281 if (DEFAULT_ABS_PREFERENCE == c->f_abs_sum[kind])
282 /* No peer has a preference for this property,
283 * so set default preference */
284 p_cur->f_rel[kind] = DEFAULT_REL_PREFERENCE;
286 p_cur->f_rel[kind] = (c->f_abs_sum[kind] + p_cur->f_abs[kind])
287 / c->f_abs_sum[kind];
289 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
290 "Client %p: peer `%s' has relative preference for %s of %.3f\n",
291 c->client, GNUNET_i2s (&p_cur->id),
292 GNUNET_ATS_print_preference_type (kind), p_cur->f_rel[kind]);
294 if (p_cur->f_rel[kind] != backup)
296 /* Value changed, recalculate */
297 res = update_peers (&p_cur->id, kind);
298 if (0 == memcmp (&p->id, &p_cur->id, sizeof(struct GNUNET_PeerIdentity)))
303 /* Value did not chang, return old value*/
305 NULL != (rp = GNUNET_CONTAINER_multihashmap_get (preference_peers, &p->id.hashPubKey)));
306 ret = rp->f_rel[kind];
313 * Update the absolute preference value for a peer
314 * @param c the client
316 * @param kind the preference kind
317 * @param score_abs the absolute value
318 * @return the new relative preference value
321 update_preference (struct PreferenceClient *c, struct PreferencePeer *p,
322 enum GNUNET_ATS_PreferenceKind kind, float score_abs)
324 double score = score_abs;
326 /* Update preference value according to type */
329 case GNUNET_ATS_PREFERENCE_BANDWIDTH:
330 case GNUNET_ATS_PREFERENCE_LATENCY:
331 p->f_abs[kind] = (p->f_abs[kind] + score) / 2;
332 p->next_aging[kind] = GNUNET_TIME_absolute_add (GNUNET_TIME_absolute_get(),
333 PREF_AGING_INTERVAL);
335 case GNUNET_ATS_PREFERENCE_END:
340 return recalculate_rel_preferences (c, p, kind);
344 * Reduce absolute preferences since they got old
346 * @param cls the PreferencePeer
350 preference_aging (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
352 struct PreferencePeer *p;
353 struct PreferenceClient *cur_client;
355 int values_to_update;
358 aging_task = GNUNET_SCHEDULER_NO_TASK;
359 values_to_update = 0;
362 for (cur_client = pc_head; NULL != cur_client; cur_client = cur_client->next)
364 for (p = cur_client->p_head; NULL != p; p = p->next)
366 /* Aging absolute values: */
367 for (i = 0; i < GNUNET_ATS_PreferenceCount; i++)
369 if (0 == GNUNET_TIME_absolute_get_remaining(p->next_aging[i]).rel_value_us)
371 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Aging preference for peer `%s'\n",
372 GNUNET_i2s (&p->id));
373 backup = p->f_abs[i];
374 if (p->f_abs[i] > DEFAULT_ABS_PREFERENCE)
375 p->f_abs[i] *= PREF_AGING_FACTOR;
376 if (p->f_abs[i] <= DEFAULT_ABS_PREFERENCE + PREF_EPSILON)
377 p->f_abs[i] = DEFAULT_ABS_PREFERENCE;
378 if ((p->f_abs[i] != DEFAULT_ABS_PREFERENCE) && (backup != p->f_abs[i]))
380 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
381 "Aged preference for peer `%s' from %.3f to %.3f\n",
382 GNUNET_i2s (&p->id), backup, p->f_abs[i]);
383 recalculate_rel_preferences (p->client, p, i);
384 p->next_aging[i] = GNUNET_TIME_absolute_add(GNUNET_TIME_absolute_get(),
385 PREF_AGING_INTERVAL);
393 if (values_to_update > 0)
395 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
396 "Rescheduling aging task due to %u elements to age\n", values_to_update);
397 aging_task = GNUNET_SCHEDULER_add_delayed (PREF_AGING_INTERVAL,
398 &preference_aging, NULL);
401 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
402 "No values to age left, not rescheduling aging task\n");
407 * Normalize an updated preference value
409 * @param src the client with this preference
410 * @param peer the peer to change the preference for
411 * @param kind the kind to change the preference
412 * @param score_abs the normalized score
415 GAS_normalization_normalize_preference (void *src,
416 const struct GNUNET_PeerIdentity *peer,
417 enum GNUNET_ATS_PreferenceKind kind,
420 struct PreferenceClient *c_cur;
421 struct PreferencePeer *p_cur;
422 struct PeerRelative *r_cur;
425 GNUNET_assert(NULL != src);
426 GNUNET_assert(NULL != peer);
428 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
429 "Client %p changes preference for peer `%s' for `%s' to %.2f\n", src,
430 GNUNET_i2s (peer), GNUNET_ATS_print_preference_type (kind), score_abs);
432 if (kind >= GNUNET_ATS_PreferenceCount)
438 /* Find preference client */
439 for (c_cur = pc_head; NULL != c_cur; c_cur = c_cur->next)
441 if (src == c_cur->client)
444 /* Not found: create new preference client */
447 c_cur = GNUNET_malloc (sizeof (struct PreferenceClient));
449 GNUNET_CONTAINER_DLL_insert (pc_head, pc_tail, c_cur);
450 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
451 "Adding new client %p \n", c_cur);
454 /* Find entry for peer */
455 for (p_cur = c_cur->p_head; NULL != p_cur; p_cur = p_cur->next)
456 if (0 == memcmp (&p_cur->id, peer, sizeof(p_cur->id)))
459 /* Not found: create new peer entry */
462 p_cur = GNUNET_malloc (sizeof (struct PreferencePeer));
463 p_cur->client = c_cur;
465 for (i = 0; i < GNUNET_ATS_PreferenceCount; i++)
467 /* Default value per peer absolut preference for a quality:
468 * No value set, so absolute preference 0 */
469 p_cur->f_abs[i] = DEFAULT_ABS_PREFERENCE;
470 /* Default value per peer relative preference for a quality: 1.0 */
471 p_cur->f_rel[i] = DEFAULT_REL_PREFERENCE;
472 p_cur->next_aging[i] = GNUNET_TIME_UNIT_FOREVER_ABS;
474 GNUNET_CONTAINER_DLL_insert(c_cur->p_head, c_cur->p_tail, p_cur);
477 if (NULL == GNUNET_CONTAINER_multihashmap_get (preference_peers,
480 r_cur = GNUNET_malloc (sizeof (struct PeerRelative));
482 for (i = 0; i < GNUNET_ATS_PreferenceCount; i++)
483 r_cur->f_rel[i] = DEFAULT_REL_PREFERENCE;
484 GNUNET_CONTAINER_multihashmap_put (preference_peers, &r_cur->id.hashPubKey,
485 r_cur, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
488 if (GNUNET_SCHEDULER_NO_TASK == aging_task)
489 aging_task = GNUNET_SCHEDULER_add_delayed (PREF_AGING_INTERVAL,
490 &preference_aging, NULL);
492 update_preference (c_cur, p_cur, kind, score_abs);
496 * Get the normalized preference values for a specific peer or
497 * the default values if
500 * @return pointer to the values, can be indexed with GNUNET_ATS_PreferenceKind,
501 * default preferences if peer does not exist
504 GAS_normalization_get_preferences (const struct GNUNET_PeerIdentity *id)
506 GNUNET_assert(NULL != preference_peers);
507 GNUNET_assert(NULL != id);
509 struct PeerRelative *rp;
511 == (rp = GNUNET_CONTAINER_multihashmap_get (preference_peers,
514 return defvalues.f_rel;
520 * Get the normalized properties values for a specific peer or
521 * the default values if
523 * @param address the address
524 * @return pointer to the values, can be indexed with GNUNET_ATS_PreferenceKind,
525 * default preferences if peer does not exist
528 GAS_normalization_get_properties (struct ATS_Address *address)
530 static double norm_values[GNUNET_ATS_QualityPropertiesCount];
533 GNUNET_assert(NULL != address);
535 for (i = 0; i < GNUNET_ATS_QualityPropertiesCount; i++)
537 if ((address->atsin[i].norm >= 1.0) && (address->atsin[i].norm <= 2.0))
538 norm_values[i] = address->atsin[i].norm;
540 norm_values[i] = DEFAULT_REL_QUALITY;
546 * Quality Normalization
557 struct Property properties[GNUNET_ATS_QualityPropertiesCount];
560 * Normalize a specific ATS type with the values in queue
561 * @param address the address
562 * @param atsi the ats information
563 * @return the new average or GNUNET_ATS_VALUE_UNDEFINED
567 property_average (struct ATS_Address *address,
568 const struct GNUNET_ATS_Information *atsi)
570 struct GAS_NormalizationInfo *ni;
571 uint32_t current_type;
572 uint32_t current_val;
578 unsigned int props[] = GNUNET_ATS_QualityProperties;
580 /* Average the values of this property */
581 current_type = ntohl (atsi->type);
582 current_val = ntohl (atsi->value);
584 for (c1 = 0; c1 < GNUNET_ATS_QualityPropertiesCount; c1++)
586 if (current_type == props[c1])
589 if (c1 == GNUNET_ATS_QualityPropertiesCount)
592 return GNUNET_ATS_VALUE_UNDEFINED;
596 ni = &address->atsin[index];
597 ni->atsi_abs[ni->avg_queue_index] = current_val;
598 ni->avg_queue_index++;
599 if (GAS_normalization_queue_length == ni->avg_queue_index)
600 ni->avg_queue_index = 0;
604 for (c1 = 0; c1 < GAS_normalization_queue_length; c1++)
606 if (GNUNET_ATS_VALUE_UNDEFINED != ni->atsi_abs[c1])
609 if (GNUNET_ATS_VALUE_UNDEFINED > (sum + ni->atsi_abs[c1]))
610 sum += ni->atsi_abs[c1];
613 sum = GNUNET_ATS_VALUE_UNDEFINED - 1;
618 GNUNET_assert(0 != count);
620 LOG(GNUNET_ERROR_TYPE_DEBUG,
621 "New average of `%s' created by adding %u from %u elements: %u\n",
622 GNUNET_ATS_print_property_type (current_type), current_val, count, res,
636 find_min_max_it (void *cls, const struct GNUNET_HashCode *h, void *k)
638 struct ATS_Address *a = (struct ATS_Address *) k;
639 struct FindMinMaxCtx *find_res = cls;
641 if (a->atsin[find_res->p->prop_type].avg > find_res->max)
642 find_res->max = a->atsin[find_res->p->prop_type].avg;
644 if (a->atsin[find_res->p->prop_type].avg < find_res->min)
645 find_res->min = a->atsin[find_res->p->prop_type].avg;
651 normalize_address (void *cls, const struct GNUNET_HashCode *h, void *k)
653 struct Property *p = cls;
654 struct ATS_Address *address = (struct ATS_Address *) k;
657 uint32_t avg_value = address->atsin[p->prop_type].avg;
659 delta = p->max - p->min;
660 address->atsin[p->prop_type].norm = (delta + (avg_value - p->min)) / (delta);
662 LOG(GNUNET_ERROR_TYPE_DEBUG,
663 "Normalize `%s' address %p's '%s' with value %u to range [%u..%u] = %.3f\n",
664 GNUNET_i2s (&address->peer), address,
665 GNUNET_ATS_print_property_type (p->atsi_type),
666 address->atsin[p->prop_type].avg, p->min, p->max,
667 address->atsin[p->prop_type].norm);
669 if (NULL != prop_ch_cb)
670 prop_ch_cb (prop_ch_cb_cls, address, p->atsi_type,
671 address->atsin[p->prop_type].norm);
677 * Normalize avg_value to a range of values between [1.0, 2.0]
678 * based on min max values currently known.
680 * @param addresses the address hashmap
681 * @param p the property
682 * @param address the address
683 * @param avg_value the value to normalize
687 property_normalize (struct GNUNET_CONTAINER_MultiHashMap *addresses,
688 struct Property *p, struct ATS_Address *address, uint32_t avg_value)
690 struct FindMinMaxCtx find_ctx;
696 find_ctx.min = UINT32_MAX;
697 addr_count = GNUNET_CONTAINER_multihashmap_iterate (addresses,
698 &find_min_max_it, &find_ctx);
705 limits_changed = GNUNET_NO;
706 if (find_ctx.max != p->max)
708 LOG(GNUNET_ERROR_TYPE_DEBUG,
709 "Normalizing %s: new maximum %u -> recalculate all values\n",
710 GNUNET_ATS_print_property_type (p->atsi_type), find_ctx.max);
711 p->max = find_ctx.max;
712 limits_changed = GNUNET_YES;
715 if ((find_ctx.min != p->min) && (find_ctx.min < p->max))
717 LOG(GNUNET_ERROR_TYPE_DEBUG,
718 "Normalizing %s: new minimum %u -> recalculate all values\n",
719 GNUNET_ATS_print_property_type (p->atsi_type), find_ctx.min,
721 p->min = find_ctx.min;
722 limits_changed = GNUNET_YES;
724 else if (find_ctx.min == p->max)
726 /* Only one value, so minimum has to be 0 */
730 /* Normalize the values of this property */
731 if (GNUNET_NO == limits_changed)
733 /* normalize just this address */
734 normalize_address (p, &address->peer.hashPubKey, address);
739 /* limits changed, normalize all addresses */
740 GNUNET_CONTAINER_multihashmap_iterate (addresses, &normalize_address, p);
746 * Update and normalize atsi performance information
748 * @param addresses hashmap containing all addresses
749 * @param address the address to update
750 * @param atsi the array of performance information
751 * @param atsi_count the number of atsi information in the array
754 GAS_normalization_normalize_property (
755 struct GNUNET_CONTAINER_MultiHashMap *addresses,
756 struct ATS_Address *address, const struct GNUNET_ATS_Information *atsi,
759 struct Property *cur_prop;
762 uint32_t current_type;
763 uint32_t current_val;
764 unsigned int existing_properties[] = GNUNET_ATS_QualityProperties;
766 GNUNET_assert(NULL != address);
767 GNUNET_assert(NULL != atsi);
769 LOG(GNUNET_ERROR_TYPE_DEBUG, "Updating %u elements for peer `%s'\n",
770 atsi_count, GNUNET_i2s (&address->peer));
772 for (c1 = 0; c1 < atsi_count; c1++)
774 current_type = ntohl (atsi[c1].type);
776 for (c2 = 0; c2 < GNUNET_ATS_QualityPropertiesCount; c2++)
778 /* Check if type is valid */
779 if (current_type == existing_properties[c2])
782 if (GNUNET_ATS_QualityPropertiesCount == c2)
784 /* Invalid property, continue with next element */
788 current_val = property_average (address, &atsi[c1]);
789 if (GNUNET_ATS_VALUE_UNDEFINED == current_val)
797 cur_prop = &properties[c2];
798 property_normalize (addresses, cur_prop, address, current_val);
803 * Start the normalization component
805 * @param pref_ch_cb callback to call on relative preference changing
806 * @param pref_ch_cb_cls cls for the preference callback
807 * @param property_ch_cb callback to call on relative property changing
808 * @param property_ch_cb_cls cls for the property callback
811 GAS_normalization_start (GAS_Normalization_preference_changed_cb pref_ch_cb,
812 void *pref_ch_cb_cls, GAS_Normalization_property_changed_cb property_ch_cb,
813 void *property_ch_cb_cls)
817 preference_peers = GNUNET_CONTAINER_multihashmap_create (10, GNUNET_NO);
818 property_peers = GNUNET_CONTAINER_multihashmap_create (10, GNUNET_NO);
819 unsigned int existing_properties[] = GNUNET_ATS_QualityProperties;
821 for (c1 = 0; c1 < GNUNET_ATS_QualityPropertiesCount; c1++)
823 properties[c1].prop_type = c1;
824 properties[c1].atsi_type = existing_properties[c1];
825 properties[c1].min = 0;
826 properties[c1].max = 0;
829 pref_changed_cb = pref_ch_cb;
830 pref_changed_cb_cls = pref_ch_cb_cls;
831 prop_ch_cb = property_ch_cb;
832 prop_ch_cb_cls = pref_ch_cb_cls;
837 for (i = 0; i < GNUNET_ATS_PreferenceCount; i++)
838 defvalues.f_rel[i] = DEFAULT_REL_PREFERENCE;
839 aging_task = GNUNET_SCHEDULER_NO_TASK;
848 * @param value RelativePeer
849 * @return GNUNET_OK to continue
852 free_peer (void *cls, const struct GNUNET_HashCode * key, void *value)
854 struct PeerRelative *rp = value;
856 == GNUNET_CONTAINER_multihashmap_remove (preference_peers, key, value))
864 * Stop the normalization component and free all items
867 GAS_normalization_stop ()
869 struct PreferenceClient *pc;
870 struct PreferenceClient *next_pc;
871 struct PreferencePeer *p;
872 struct PreferencePeer *next_p;
874 if (GNUNET_SCHEDULER_NO_TASK != aging_task)
876 GNUNET_SCHEDULER_cancel (aging_task);
877 aging_task = GNUNET_SCHEDULER_NO_TASK;
881 while (NULL != (pc = next_pc))
884 GNUNET_CONTAINER_DLL_remove(pc_head, pc_tail, pc);
886 while (NULL != (p = next_p))
889 GNUNET_CONTAINER_DLL_remove(pc->p_head, pc->p_tail, p);
895 GNUNET_CONTAINER_multihashmap_iterate (preference_peers, &free_peer, NULL );
896 GNUNET_CONTAINER_multihashmap_destroy (preference_peers);
897 GNUNET_CONTAINER_multihashmap_destroy (property_peers);
901 /* end of gnunet-service-ats_normalization.c */