deprecated auto_expand_choker. started factoring out choker logic into its own translation unit (preparing for making it unit testable)

This commit is contained in:
Arvid Norberg 2014-10-22 22:06:56 +00:00
parent 907dc9dddd
commit 02a9ea18b7
13 changed files with 276 additions and 165 deletions

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@ -16,6 +16,7 @@ set(sources
block_cache
bloom_filter
chained_buffer
choker
crc32c
create_torrent
disk_buffer_holder

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@ -1,3 +1,4 @@
* removed auto_expand_choker. use rate_based_choker instead
* optimize UDP tracker packet handling
* support SSL over uTP connections
* support web seeds that resolve to multiple IPs

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@ -512,6 +512,7 @@ SOURCES =
block_cache
bloom_filter
chained_buffer
choker
crc32c
create_torrent
disk_buffer_holder

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@ -25,6 +25,7 @@ nobase_include_HEADERS = \
build_config.hpp \
byteswap.hpp \
chained_buffer.hpp \
choker.hpp \
config.hpp \
ConvertUTF.h \
copy_ptr.hpp \

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@ -627,7 +627,7 @@ namespace libtorrent
void update_i2p_bridge();
void update_peer_tos();
void update_user_agent();
void update_choking_algorithm();
void update_unchoke_limit();
void update_connection_speed();
void update_queued_disk_bytes();
void update_alert_queue_size();

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@ -0,0 +1,52 @@
/*
Copyright (c) 2014, Arvid Norberg
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in
the documentation and/or other materials provided with the distribution.
* Neither the name of the author nor the names of its
contributors may be used to endorse or promote products derived
from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
*/
#include "libtorrent/config.hpp"
#include "libtorrent/time.hpp" // for time_duration
#include <vector>
namespace libtorrent
{
namespace aux { struct session_settings; }
class peer_connection;
// sorts the vector of peers in-place. When returning, the top unchoke slots
// elements are the peers we should unchoke. This is similar to a partial
// sort. Only the unchoke slots first elements are sorted.
// the return value are the number of peers that should be unchoked. This
// is also the number of elements that are valid at the beginning of the
// peer list. Peers bayond this initial range are not sorted.
TORRENT_EXTRA_EXPORT int unchoke_sort(std::vector<peer_connection*>& peers
, int max_upload_rate, time_duration unchoke_interval
, aux::session_settings const& sett);
}

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@ -443,18 +443,21 @@ namespace libtorrent
{
// the traditional choker with a fixed number of unchoke slots, as
// specified by session::set_max_uploads()..
fixed_slots_choker,
fixed_slots_choker = 0,
#ifndef TORRENT_NO_DEPRECATE
// opens at least the number of slots as specified by
// session::set_max_uploads() but opens up more slots if the upload
// capacity is not saturated. This unchoker will work just like the
// ``fixed_slot_choker`` if there's no global upload rate limit set.
auto_expand_choker,
auto_expand_choker = 1,
#endif
// opens up unchoke slots based on the upload rate achieved to peers.
// The more slots that are opened, the marginal upload rate required
// to open up another slot increases.
rate_based_choker,
rate_based_choker = 1,
// attempts to optimize download rate by finding the reciprocation
// rate of each peer individually and prefers peers that gives the
// highest *return on investment*. It still allocates all upload
@ -464,7 +467,7 @@ namespace libtorrent
// this choker, see the paper_.
//
// .. _paper: http://bittyrant.cs.washington.edu/#papers
bittyrant_choker
bittyrant_choker = 2
};
// specifies which algorithm to use to determine which peers to unchoke.

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@ -842,11 +842,6 @@ namespace libtorrent
// * ``fixed_slots_choker`` is the traditional choker with a fixed number of unchoke
// slots (as specified by ``session::set_max_uploads()``).
//
// * ``auto_expand_choker`` opens at least the number of slots as specified by
// ``session::set_max_uploads()`` but opens up more slots if the upload capacity
// is not saturated. This unchoker will work just like the ``fixed_slots_choker``
// if there's no global upload rate limit set.
//
// * ``rate_based_choker`` opens up unchoke slots based on the upload rate
// achieved to peers. The more slots that are opened, the marginal upload
// rate required to open up another slot increases.
@ -1474,10 +1469,9 @@ namespace libtorrent
enum choking_algorithm_t
{
fixed_slots_choker,
auto_expand_choker,
rate_based_choker,
bittyrant_choker
fixed_slots_choker = 0,
rate_based_choker = 2,
bittyrant_choker = 3
};
enum seed_choking_algorithm_t

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@ -48,6 +48,7 @@ libtorrent_rasterbar_la_SOURCES = \
block_cache.cpp \
bt_peer_connection.cpp \
chained_buffer.cpp \
choker.cpp \
ConvertUTF.cpp \
crc32c.cpp \
create_torrent.cpp \

170
src/choker.cpp Normal file
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@ -0,0 +1,170 @@
/*
Copyright (c) 2014, Arvid Norberg
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in
the documentation and/or other materials provided with the distribution.
* Neither the name of the author nor the names of its
contributors may be used to endorse or promote products derived
from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
*/
#include "libtorrent/choker.hpp"
#include "libtorrent/peer_connection.hpp"
#include "libtorrent/aux_/session_settings.hpp"
#include <boost/bind.hpp>
namespace libtorrent
{
int unchoke_sort(std::vector<peer_connection*>& peers
, int max_upload_rate
, time_duration unchoke_interval
, aux::session_settings const& sett)
{
int upload_slots = sett.get_int(settings_pack::unchoke_slots_limit);
// ==== BitTyrant ====
//
// if we're using the bittyrant unchoker, go through all peers that
// we have unchoked already, and adjust our estimated reciprocation
// rate. If the peer has reciprocated, lower the estimate, if it hasn't,
// increase the estimate (this attempts to optimize "ROI" of upload
// capacity, by sending just enough to be reciprocated).
// For more information, see: http://bittyrant.cs.washington.edu/
if (sett.get_int(settings_pack::choking_algorithm)
== settings_pack::bittyrant_choker)
{
for (std::vector<peer_connection*>::const_iterator i = peers.begin()
, end(peers.end()); i != end; ++i)
{
peer_connection* p = *i;
if (p->is_choked() || !p->is_interesting()) continue;
if (!p->has_peer_choked())
{
// we're unchoked, we may want to lower our estimated
// reciprocation rate
p->decrease_est_reciprocation_rate();
}
else
{
// we've unchoked this peer, and it hasn't reciprocated
// we may want to increase our estimated reciprocation rate
p->increase_est_reciprocation_rate();
}
}
// if we're using the bittyrant choker, sort peers by their return
// on investment. i.e. download rate / upload rate
// TODO: make the comparison function a free function and move it
// into this source file
std::sort(peers.begin(), peers.end()
, boost::bind(&peer_connection::bittyrant_unchoke_compare, _1, _2));
int upload_capacity_left = max_upload_rate;
// now, figure out how many peers should be unchoked. We deduct the
// estimated reciprocation rate from our upload_capacity estimate
// until there none left
upload_slots = 0;
for (std::vector<peer_connection*>::iterator i = peers.begin()
, end(peers.end()); i != end; ++i)
{
peer_connection* p = *i;
TORRENT_ASSERT(p);
if (p->est_reciprocation_rate() > upload_capacity_left) break;
++upload_slots;
upload_capacity_left -= p->est_reciprocation_rate();
}
return upload_slots;
}
// ==== rate-based ====
//
// The rate based unchoker looks at our upload rate to peers, and find
// a balance between number of upload slots and the rate we achieve. The
// intention is to not spread upload bandwidth too thin, but also to not
// unchoke few enough peers to not be able to saturate the up-link.
// this is done by traversing the peers sorted by our upload rate to
// them in decreasing rates. For each peer we increase our threshold
// by 1 kB/s. The first peer we get to to whom we upload slower than
// the threshold, we stop and that's the number of unchoke slots we have.
if (sett.get_int(settings_pack::choking_algorithm)
== settings_pack::rate_based_choker)
{
// first reset the number of unchoke slots, because we'll calculate
// it purely based on the current state of our peers.
upload_slots = 0;
// TODO: optimize this using partial_sort or something. We don't need
// to sort the entire list
// TODO: make the comparison function a free function and move it
// into this cpp file
std::sort(peers.begin(), peers.end()
, boost::bind(&peer_connection::upload_rate_compare, _1, _2));
// TODO: make configurable
int rate_threshold = 1024;
for (std::vector<peer_connection*>::const_iterator i = peers.begin()
, end(peers.end()); i != end; ++i)
{
peer_connection const& p = **i;
int rate = int(p.uploaded_in_last_round()
* 1000 / total_milliseconds(unchoke_interval));
if (rate < rate_threshold) break;
++upload_slots;
// TODO: make configurable
rate_threshold += 1024;
}
++upload_slots;
}
// sorts the peers that are eligible for unchoke by download rate and secondary
// by total upload. The reason for this is, if all torrents are being seeded,
// the download rate will be 0, and the peers we have sent the least to should
// be unchoked
// TODO: use partial_sort
// TODO: make the comparison function a free function and move it into
// this cpp file
std::sort(peers.begin(), peers.end()
, boost::bind(&peer_connection::unchoke_compare, _1, _2));
return upload_slots;
}
}

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@ -93,6 +93,7 @@ POSSIBILITY OF SUCH DAMAGE.
#include "libtorrent/magnet_uri.hpp"
#include "libtorrent/aux_/session_settings.hpp"
#include "libtorrent/torrent_peer.hpp"
#include "libtorrent/choker.hpp"
#if defined TORRENT_VERBOSE_LOGGING
#include "libtorrent/socket_io.hpp"
@ -599,7 +600,7 @@ namespace aux {
update_download_rate();
update_upload_rate();
update_connections_limit();
update_choking_algorithm();
update_unchoke_limit();
update_disk_threads();
update_network_threads();
update_upnp();
@ -3869,28 +3870,10 @@ retry:
torrent* t = p->associated_torrent().lock().get();
torrent_peer* pi = p->peer_info_struct();
if (p->ignore_unchoke_slots() || t == 0 || pi == 0 || pi->web_seed || t->is_paused())
if (p->ignore_unchoke_slots() || t == 0 || pi == 0
|| pi->web_seed || t->is_paused())
continue;
if (m_settings.get_int(settings_pack::choking_algorithm) == settings_pack::bittyrant_choker)
{
if (!p->is_choked() && p->is_interesting())
{
if (!p->has_peer_choked())
{
// we're unchoked, we may want to lower our estimated
// reciprocation rate
p->decrease_est_reciprocation_rate();
}
else
{
// we've unchoked this peer, and it hasn't reciprocated
// we may want to increase our estimated reciprocation rate
p->increase_est_reciprocation_rate();
}
}
}
if (!p->is_peer_interested()
|| p->is_disconnecting()
|| p->is_connecting())
@ -3910,116 +3893,34 @@ retry:
t->choke_peer(*p);
continue;
}
peers.push_back(p.get());
}
if (m_settings.get_int(settings_pack::choking_algorithm) == settings_pack::rate_based_choker)
// the unchoker wants an estimate of our upload rate capacity
// (used by bittyrant)
int max_upload_rate = upload_rate_limit(m_global_class);
if (m_settings.get_int(settings_pack::choking_algorithm)
== settings_pack::bittyrant_choker
&& max_upload_rate == 0)
{
m_allowed_upload_slots = 0;
std::sort(peers.begin(), peers.end()
, boost::bind(&peer_connection::upload_rate_compare, _1, _2));
#ifdef TORRENT_DEBUG
for (std::vector<peer_connection*>::const_iterator i = peers.begin()
, end(peers.end()), prev(peers.end()); i != end; ++i)
{
if (prev != end)
{
boost::shared_ptr<torrent> t1 = (*prev)->associated_torrent().lock();
TORRENT_ASSERT(t1);
boost::shared_ptr<torrent> t2 = (*i)->associated_torrent().lock();
TORRENT_ASSERT(t2);
TORRENT_ASSERT((*prev)->uploaded_in_last_round() * 1000
* (1 + t1->priority()) / total_milliseconds(unchoke_interval)
>= (*i)->uploaded_in_last_round() * 1000
* (1 + t2->priority()) / total_milliseconds(unchoke_interval));
}
prev = i;
}
#endif
// TODO: make configurable
int rate_threshold = 1024;
for (std::vector<peer_connection*>::const_iterator i = peers.begin()
, end(peers.end()); i != end; ++i)
{
peer_connection const& p = **i;
int rate = int(p.uploaded_in_last_round()
* 1000 / total_milliseconds(unchoke_interval));
if (rate < rate_threshold) break;
++m_allowed_upload_slots;
// TODO: make configurable
rate_threshold += 1024;
}
// allow one optimistic unchoke
++m_allowed_upload_slots;
// we don't know at what rate we can upload. If we have a
// measurement of the peak, use that + 10kB/s, otherwise
// assume 20 kB/s
max_upload_rate = (std::max)(20000, m_peak_up_rate + 10000);
if (m_alerts.should_post<performance_alert>())
m_alerts.post_alert(performance_alert(torrent_handle()
, performance_alert::bittyrant_with_no_uplimit));
}
if (m_settings.get_int(settings_pack::choking_algorithm) == settings_pack::bittyrant_choker)
{
// if we're using the bittyrant choker, sort peers by their return
// on investment. i.e. download rate / upload rate
std::sort(peers.begin(), peers.end()
, boost::bind(&peer_connection::bittyrant_unchoke_compare, _1, _2));
}
else
{
// sorts the peers that are eligible for unchoke by download rate and secondary
// by total upload. The reason for this is, if all torrents are being seeded,
// the download rate will be 0, and the peers we have sent the least to should
// be unchoked
std::sort(peers.begin(), peers.end()
, boost::bind(&peer_connection::unchoke_compare, _1, _2));
}
// auto unchoke
peer_class* gpc = m_classes.at(m_global_class);
int upload_limit = gpc->channel[peer_connection::upload_channel].throttle();
if (m_settings.get_int(settings_pack::choking_algorithm) == settings_pack::auto_expand_choker
&& upload_limit > 0)
{
// if our current upload rate is less than 90% of our
// limit
if (m_stat.upload_rate() < upload_limit * 0.9f
&& m_allowed_upload_slots
<= m_stats_counters[counters::num_peers_up_unchoked] + 1
&& m_upload_rate.queue_size() < 2)
{
++m_allowed_upload_slots;
}
else if (m_upload_rate.queue_size() > 1
&& m_allowed_upload_slots > m_settings.get_int(settings_pack::unchoke_slots_limit)
&& m_settings.get_int(settings_pack::unchoke_slots_limit) >= 0)
{
--m_allowed_upload_slots;
}
}
m_allowed_upload_slots = unchoke_sort(peers, max_upload_rate
, unchoke_interval, m_settings);
int num_opt_unchoke = m_settings.get_int(settings_pack::num_optimistic_unchoke_slots);
if (num_opt_unchoke == 0) num_opt_unchoke = (std::max)(1, m_allowed_upload_slots / 5);
// reserve some upload slots for optimistic unchokes
int unchoke_set_size = m_allowed_upload_slots - num_opt_unchoke;
int upload_capacity_left = 0;
if (m_settings.get_int(settings_pack::choking_algorithm) == settings_pack::bittyrant_choker)
{
upload_capacity_left = upload_rate_limit(m_global_class);
if (upload_capacity_left == 0)
{
// we don't know at what rate we can upload. If we have a
// measurement of the peak, use that + 10kB/s, otherwise
// assume 20 kB/s
upload_capacity_left = (std::max)(20000, m_peak_up_rate + 10000);
if (m_alerts.should_post<performance_alert>())
m_alerts.post_alert(performance_alert(torrent_handle()
, performance_alert::bittyrant_with_no_uplimit));
}
}
int unchoke_set_size = m_allowed_upload_slots;
// go through all the peers and unchoke the first ones and choke
// all the other ones.
@ -4037,22 +3938,8 @@ retry:
torrent* t = p->associated_torrent().lock().get();
TORRENT_ASSERT(t);
// if this peer should be unchoked depends on different things
// in different unchoked schemes
bool unchoke = false;
if (m_settings.get_int(settings_pack::choking_algorithm) == settings_pack::bittyrant_choker)
if (unchoke_set_size > 0)
{
unchoke = p->est_reciprocation_rate() <= upload_capacity_left;
}
else
{
unchoke = unchoke_set_size > 0;
}
if (unchoke)
{
upload_capacity_left -= p->est_reciprocation_rate();
// yes, this peer should be unchoked
if (p->is_choked())
{
@ -5835,23 +5722,20 @@ retry:
m_settings.set_str(settings_pack::user_agent, agent);
}
void session_impl::update_choking_algorithm()
void session_impl::update_unchoke_limit()
{
int algo = m_settings.get_int(settings_pack::choking_algorithm);
int unchoke_limit = m_settings.get_int(settings_pack::unchoke_slots_limit);
if (algo == settings_pack::fixed_slots_choker)
m_allowed_upload_slots = unchoke_limit;
else if (algo == settings_pack::auto_expand_choker)
m_allowed_upload_slots = unchoke_limit;
m_allowed_upload_slots = unchoke_limit;
if (m_allowed_upload_slots < 0)
m_allowed_upload_slots = (std::numeric_limits<int>::max)();
m_stats_counters.set_value(counters::num_unchoke_slots
, m_allowed_upload_slots);
if (m_settings.get_int(settings_pack::num_optimistic_unchoke_slots) >= m_allowed_upload_slots / 2)
if (m_settings.get_int(settings_pack::num_optimistic_unchoke_slots)
>= m_allowed_upload_slots / 2)
{
if (m_alerts.should_post<performance_alert>())
m_alerts.post_alert(performance_alert(torrent_handle()
@ -6642,8 +6526,7 @@ retry:
std::set<peer_connection*> unique_peers;
#endif
TORRENT_ASSERT(m_settings.get_int(settings_pack::connections_limit) > 0);
if (m_settings.get_int(settings_pack::choking_algorithm) == settings_pack::auto_expand_choker)
TORRENT_ASSERT(m_allowed_upload_slots >= m_settings.get_int(settings_pack::unchoke_slots_limit));
int unchokes = 0;
int unchokes_all = 0;
int num_optimistic = 0;

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@ -236,7 +236,7 @@ namespace libtorrent
SET(send_buffer_low_watermark, 512, 0),
SET(send_buffer_watermark, 500 * 1024, 0),
SET(send_buffer_watermark_factor, 50, 0),
SET(choking_algorithm, settings_pack::fixed_slots_choker, &session_impl::update_choking_algorithm),
SET(choking_algorithm, settings_pack::fixed_slots_choker, 0),
SET(seed_choking_algorithm, settings_pack::round_robin, 0),
SET(cache_size, 1024, 0),
SET(cache_buffer_chunk_size, 0, &session_impl::update_cache_buffer_chunk_size),
@ -292,7 +292,7 @@ namespace libtorrent
DEPRECATED_SET(local_upload_rate_limit, 0, &session_impl::update_local_upload_rate),
DEPRECATED_SET(local_download_rate_limit, 0, &session_impl::update_local_download_rate),
SET(dht_upload_rate_limit, 4000, &session_impl::update_dht_upload_rate_limit),
SET(unchoke_slots_limit, 8, &session_impl::update_choking_algorithm),
SET(unchoke_slots_limit, 8, &session_impl::update_unchoke_limit),
DEPRECATED_SET(half_open_limit, 0, 0),
SET(connections_limit, 200, &session_impl::update_connections_limit),
SET(connections_slack, 10, 0),

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@ -57,16 +57,19 @@ void test_swarm()
// this is to avoid everything finish from a single peer
// immediately. To make the swarm actually connect all
// three peers before finishing.
float rate_limit = 100000;
float rate_limit = 50000;
settings_pack pack;
pack.set_int(settings_pack::alert_mask, alert::all_categories);
pack.set_bool(settings_pack::allow_multiple_connections_per_ip, true);
pack.set_int(settings_pack::choking_algorithm, settings_pack::auto_expand_choker);
pack.set_int(settings_pack::choking_algorithm, settings_pack::rate_based_choker);
pack.set_int(settings_pack::upload_rate_limit, rate_limit);
pack.set_int(settings_pack::unchoke_slots_limit, 1);
pack.set_int(settings_pack::max_retry_port_bind, 900);
pack.set_str(settings_pack::listen_interfaces, "0.0.0.0:48010");
pack.set_bool(settings_pack::enable_natpmp, false);
pack.set_bool(settings_pack::enable_upnp, false);
pack.set_bool(settings_pack::enable_dht, false);
pack.set_int(settings_pack::out_enc_policy, settings_pack::pe_forced);
pack.set_int(settings_pack::in_enc_policy, settings_pack::pe_forced);
@ -76,6 +79,7 @@ void test_swarm()
pack.set_int(settings_pack::upload_rate_limit, rate_limit / 10);
pack.set_int(settings_pack::download_rate_limit, rate_limit / 5);
pack.set_int(settings_pack::unchoke_slots_limit, 0);
pack.set_int(settings_pack::choking_algorithm, settings_pack::fixed_slots_choker);
pack.set_str(settings_pack::listen_interfaces, "0.0.0.0:49010");
lt::session ses2(pack, fingerprint("LT", 0, 1, 0, 0));
@ -93,7 +97,7 @@ void test_swarm()
session_status st = ses1.status();
fprintf(stderr, "st.allowed_upload_slots: %d\n", st.allowed_upload_slots);
TEST_EQUAL(st.allowed_upload_slots, 1);
for (int i = 0; i < 100; ++i)
for (int i = 0; i < 200; ++i)
{
print_alerts(ses1, "ses1");
print_alerts(ses2, "ses2");
@ -107,7 +111,7 @@ void test_swarm()
torrent_status st2 = tor2.status();
torrent_status st3 = tor3.status();
print_ses_rate(i, &st1, &st2, &st3);
print_ses_rate(i / 10.f, &st1, &st2, &st3);
test_sleep(100);
}