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fixes and a rebase

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This commit is contained in:
Kajari Ghosh 2018-04-20 08:50:59 -04:00
parent 0fb706866c
commit e4a4a8d91a
1 changed files with 28 additions and 43 deletions
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71
include/engine/unpacking_cache.hpp
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@ -7,36 +7,23 @@
#include "../../third_party/compute_detail/lru_cache.hpp"
#include "util/typedefs.hpp"
// sizeof size_t: 8
// sizeof unsigned: 4
// sizeof unchar: 1
// sizeof uint32: 4
namespace osrm
{
namespace engine
{
typedef unsigned char ExcludeIndex;
typedef unsigned Timestamp;
typedef std::tuple<NodeID, NodeID, ExcludeIndex> Key;
typedef std::size_t HashedKey;
struct HashKey
{
std::size_t operator()(Key const &key) const noexcept
{
std::size_t h1 = std::hash<NodeID>{}(std::get<0>(key));
std::size_t h2 = std::hash<NodeID>{}(std::get<1>(key));
std::size_t h3 = std::hash<ExcludeIndex>{}(std::get<2>(key));
std::size_t seed = 0;
boost::hash_combine(seed, h1);
boost::hash_combine(seed, h2);
boost::hash_combine(seed, h3);
return seed;
}
};
typedef std::tuple<NodeID, NodeID, unsigned char> Key;
class UnpackingCache
{
private:
boost::compute::detail::lru_cache<HashedKey, EdgeDuration> m_cache;
boost::compute::detail::lru_cache<std::tuple<NodeID, NodeID, unsigned char>, EdgeDuration> m_cache;
unsigned m_current_data_timestamp = 0;
public:
@ -45,27 +32,28 @@ class UnpackingCache
// https://github.com/Project-OSRM/osrm-backend/issues/4798#issue-288608332)
// LRU CACHE IMPLEMENTATION HAS THESE TWO STORAGE CONTAINERS
// map: n * tuple_hash + n * EdgeDuration
// = n * std::size_t + n * std::int32_t
// = n * 8 bytes + n * 4 bytes
// = n * 12 bytes
// list: n * HashedKey
// = n * std::size_t
// = n * 8 bytes
// Total = n * 20 bytes
// Key is of size: std::uint32_t * 2 + (unsigned char) * 1 + unsigned * 1
// = 4 * 2 + 1 * 1 + 4 * 1 = 21
// map: n * Key + n * EdgeDuration
// = n * 21 bytes + n * std::int32_t
// = n * 21 bytes + n * 4 bytes
// = n * 25 bytes
// list: n * Key
// = n * 21 bytes
// Total = n * (25 + 21) = n * 46 bytes
// Total cache size: 500 mb = 500 * 1024 *1024 bytes = 524288000 bytes
// THREAD LOCAL STORAGE
// Number of lines we need = 524288000 / 20 / number of threads = 26214400 / number of threads
// 16 threads: 26214400 / 16 = 1638400
// 8 threads: 26214400 / 8 = 3276800
// 4 threads: 26214400 / 4 = 6553600
// 2 threads: 26214400 / 2 = 13107200
// Number of lines we need = 524288000 / 46 / number of threads = 11397565 / number of threads
// 16 threads: 11397565 / 16 = 712347
// 8 threads: 11397565 / 8 = 1424695
// 4 threads: 11397565 / 4 = 2849391
// 2 threads: 11397565 / 2 = 5698782
// SHARED STORAGE CACHE
// Number of lines we need for shared storage cache = 524288000 / 20 = 26214400
UnpackingCache(unsigned timestamp) : m_cache(13107200), m_current_data_timestamp(timestamp){};
UnpackingCache(unsigned timestamp) : m_cache(712347), m_current_data_timestamp(timestamp){};
UnpackingCache(std::size_t cache_size, unsigned timestamp)
: m_cache(cache_size), m_current_data_timestamp(timestamp){};
@ -79,22 +67,19 @@ class UnpackingCache
}
}
bool IsEdgeInCache(Key edge)
bool IsEdgeInCache(std::tuple<NodeID, NodeID, unsigned char> edge)
{
HashedKey hashed_edge = HashKey{}(edge);
return m_cache.contains(hashed_edge);
return m_cache.contains(edge);
}
void AddEdge(Key edge, EdgeDuration duration)
void AddEdge(std::tuple<NodeID, NodeID, unsigned char> edge, EdgeDuration duration)
{
HashedKey hashed_edge = HashKey{}(edge);
m_cache.insert(hashed_edge, duration);
m_cache.insert(edge, duration);
}
EdgeDuration GetDuration(Key edge)
EdgeDuration GetDuration(std::tuple<NodeID, NodeID, unsigned char> edge)
{
HashedKey hashed_edge = HashKey{}(edge);
boost::optional<EdgeDuration> duration = m_cache.get(hashed_edge);
boost::optional<EdgeDuration> duration = m_cache.get(edge);
return duration ? *duration : MAXIMAL_EDGE_DURATION;
}
};