1 files changed, 82 insertions, 247 deletions

diff --git a/include/shard/VPTree.h b/include/shard/VPTree.h
index 8feec84..b342fe6 100644
--- a/include/shard/VPTree.h
+++ b/include/shard/VPTree.h
@@ -1,97 +1,31 @@
 /*
  * include/shard/VPTree.h
  *
- * Copyright (C) 2023 Douglas Rumbaugh <drumbaugh@psu.edu>
+ * Copyright (C) 2023 Douglas B. Rumbaugh <drumbaugh@psu.edu>
  *
- * All outsides reserved. Published under the Modified BSD License.
+ * Distributed under the Modified BSD License.
  *
+ * A shard shim around a VPTree for high-dimensional metric similarity
+ * search.
+ *
+ * FIXME: Does not yet support the tombstone delete policy.
+ * TODO: The code in this file is very poorly commented.
  */
 #pragma once
 
 #include <vector>
-#include <cassert>
-#include <queue>
-#include <memory>
-#include <concepts>
-#include <map>
 
+#include <unordered_map>
+#include "framework/ShardRequirements.h"
 #include "psu-ds/PriorityQueue.h"
-#include "util/Cursor.h"
-#include "psu-ds/BloomFilter.h"
-#include "util/bf_config.h"
-#include "framework/MutableBuffer.h"
-#include "framework/RecordInterface.h"
-#include "framework/ShardInterface.h"
-#include "framework/QueryInterface.h"
 
 using psudb::CACHELINE_SIZE;
-using psudb::BloomFilter;
 using psudb::PriorityQueue;
 using psudb::queue_record;
-using psudb::Alias;
+using psudb::byte;
 
 namespace de {
 
-template <NDRecordInterface R>
-struct KNNQueryParms {
-    R point;
-    size_t k;
-};
-
-template <NDRecordInterface R>
-class KNNQuery;
-
-template <NDRecordInterface R>
-struct KNNState {
-    size_t k;
-
-    KNNState() {
-        k = 0;
-    }
-};
-
-template <NDRecordInterface R>
-struct KNNBufferState {
-
-};
-
-
-template <typename R>
-class KNNDistCmpMax {
-public:
-    KNNDistCmpMax(R *baseline) : P(baseline) {}
-
-    inline bool operator()(const R *a, const R *b) requires WrappedInterface<R> {
-        return a->rec.calc_distance(P->rec) > b->rec.calc_distance(P->rec); 
-    }
-
-    inline bool operator()(const R *a, const R *b) requires (!WrappedInterface<R>){
-        return a->calc_distance(*P) > b->calc_distance(*P); 
-    }
-
-private:
-    R *P;
-};
-
-template <typename R>
-class KNNDistCmpMin {
-public:
-    KNNDistCmpMin(R *baseline) : P(baseline) {}
-
-    inline bool operator()(const R *a, const R *b) requires WrappedInterface<R> {
-        return a->rec.calc_distance(P->rec) < b->rec.calc_distance(P->rec); 
-    }
-
-    inline bool operator()(const R *a, const R *b) requires (!WrappedInterface<R>){
-        return a->calc_distance(*P) < b->calc_distance(*P); 
-    }
-
-private:
-    R *P;
-};
-
-
-
 template <NDRecordInterface R, size_t LEAFSZ=100, bool HMAP=false>
 class VPTree {
 private:
@@ -112,16 +46,19 @@ private:
         }
     };
 
-public:
-    friend class KNNQuery<R>;
 
-    VPTree(MutableBuffer<R>* buffer)
+
+public:
+    VPTree(BufferView<R> buffer)
     : m_reccnt(0), m_tombstone_cnt(0), m_root(nullptr), m_node_cnt(0) {
 
-        m_alloc_size = (buffer->get_record_count() * sizeof(Wrapped<R>)) + (CACHELINE_SIZE - (buffer->get_record_count() * sizeof(Wrapped<R>)) % CACHELINE_SIZE);
-        assert(m_alloc_size % CACHELINE_SIZE == 0);
-        m_data = (Wrapped<R>*)std::aligned_alloc(CACHELINE_SIZE, m_alloc_size);
-        m_ptrs = new Wrapped<R>*[buffer->get_record_count()];
+
+        m_alloc_size = psudb::sf_aligned_alloc(CACHELINE_SIZE, 
+                                               buffer.get_record_count() * 
+                                                 sizeof(Wrapped<R>), 
+                                               (byte**) &m_data);
+
+        m_ptrs = new Wrapped<R>*[buffer.get_record_count()];
 
         size_t offset = 0;
         m_reccnt = 0;
@@ -130,8 +67,8 @@ public:
         //        this one will likely require the multi-pass
         //        approach, as otherwise we'll need to sort the
         //        records repeatedly on each reconstruction.
-        for (size_t i=0; i<buffer->get_record_count(); i++) {
-            auto rec = buffer->get_data() + i;
+        for (size_t i=0; i<buffer.get_record_count(); i++) {
+            auto rec = buffer.get(i);
 
             if (rec->is_deleted()) {
                 continue;
@@ -149,25 +86,24 @@ public:
         }
     }
 
-    VPTree(VPTree** shards, size_t len)
+    VPTree(std::vector<VPTree*> shards) 
     : m_reccnt(0), m_tombstone_cnt(0), m_root(nullptr), m_node_cnt(0) {
 
         size_t attemp_reccnt = 0;
-
-        for (size_t i=0; i<len; i++) {
+        for (size_t i=0; i<shards.size(); i++) {
             attemp_reccnt += shards[i]->get_record_count();
         }
-        
-        m_alloc_size = (attemp_reccnt * sizeof(Wrapped<R>)) + (CACHELINE_SIZE - (attemp_reccnt * sizeof(Wrapped<R>)) % CACHELINE_SIZE);
-        assert(m_alloc_size % CACHELINE_SIZE == 0);
-        m_data = (Wrapped<R>*)std::aligned_alloc(CACHELINE_SIZE, m_alloc_size);
+
+        m_alloc_size = psudb::sf_aligned_alloc(CACHELINE_SIZE, 
+                                               attemp_reccnt * sizeof(Wrapped<R>),
+                                               (byte **) &m_data);
         m_ptrs = new Wrapped<R>*[attemp_reccnt];
 
         // FIXME: will eventually need to figure out tombstones
         //        this one will likely require the multi-pass
         //        approach, as otherwise we'll need to sort the
         //        records repeatedly on each reconstruction.
-        for (size_t i=0; i<len; i++) {
+        for (size_t i=0; i<shards.size(); i++) {
             for (size_t j=0; j<shards[i]->get_record_count(); j++) {
                 if (shards[i]->get_record_at(j)->is_deleted()) {
                     continue;
@@ -186,9 +122,9 @@ public:
    }
 
     ~VPTree() {
-        if (m_data) free(m_data);
-        if (m_root) delete m_root;
-        if (m_ptrs) delete[] m_ptrs;
+        free(m_data);
+        delete m_root;
+        delete[] m_ptrs;
     }
 
     Wrapped<R> *point_lookup(const R &rec, bool filter=false) {
@@ -242,7 +178,28 @@ public:
         return m_node_cnt * sizeof(vpnode) + m_reccnt * sizeof(R*) + m_alloc_size;
     }
 
+    size_t get_aux_memory_usage() {
+        // FIXME: need to return the size of the unordered_map
+        return 0;
+    }
+
+    void search(const R &point, size_t k, PriorityQueue<Wrapped<R>, 
+                DistCmpMax<Wrapped<R>>> &pq) {
+        double farthest = std::numeric_limits<double>::max();
+        
+        internal_search(m_root, point, k, pq, &farthest);
+    }
+
 private:
+    Wrapped<R>* m_data;
+    Wrapped<R>** m_ptrs;
+    std::unordered_map<R, size_t, RecordHash<R>> m_lookup_map;
+    size_t m_reccnt;
+    size_t m_tombstone_cnt;
+    size_t m_node_cnt;
+    size_t m_alloc_size;
+
+    vpnode *m_root;
 
     vpnode *build_vptree() {
         if (m_reccnt == 0) {
@@ -277,13 +234,15 @@ private:
     }
 
     vpnode *build_subtree(size_t start, size_t stop, gsl_rng *rng) {
-        // base-case: sometimes happens (probably because of the +1 and -1
-        // in the first recursive call)
+        /* 
+         * base-case: sometimes happens (probably because of the +1 and -1
+         * in the first recursive call)
+         */
         if (start > stop) {
             return nullptr;
         }
 
-        // base-case: create a leaf node
+        /* base-case: create a leaf node */
         if (stop - start <= LEAFSZ) {
             vpnode *node = new vpnode();
             node->start = start;
@@ -294,26 +253,30 @@ private:
             return node;
         }
 
-        // select a random element to be the root of the
-        // subtree
+        /* 
+         * select a random element to be the root of the
+         * subtree
+         */
         auto i = start + gsl_rng_uniform_int(rng, stop - start + 1);
         swap(start, i);
 
-        // partition elements based on their distance from the start,
-        // with those elements with distance falling below the median
-        // distance going into the left sub-array and those above 
-        // the median in the right. This is easily done using QuickSelect.
+        /* 
+         * partition elements based on their distance from the start,
+         * with those elements with distance falling below the median
+         * distance going into the left sub-array and those above 
+         * the median in the right. This is easily done using QuickSelect.
+         */
         auto mid = (start + 1 + stop) / 2;
         quickselect(start + 1, stop, mid, m_ptrs[start], rng);
 
-        // Create a new node based on this partitioning
+        /* Create a new node based on this partitioning */
         vpnode *node = new vpnode();
         node->start = start;
 
-        // store the radius of the circle used for partitioning the node.
+        /* store the radius of the circle used for partitioning the node. */
         node->radius = m_ptrs[start]->rec.calc_distance(m_ptrs[mid]->rec);
 
-        // recursively construct the left and right subtrees
+        /* recursively construct the left and right subtrees */
         node->inside = build_subtree(start + 1, mid-1, rng); 
         node->outside = build_subtree(mid, stop, rng);
 
@@ -322,7 +285,8 @@ private:
         return node;
     }
 
-
+    // TODO: The quickselect code can probably be generalized and moved out
+    //       to psudb-common instead.
     void quickselect(size_t start, size_t stop, size_t k, Wrapped<R> *p, gsl_rng *rng) {
         if (start == stop) return;
 
@@ -335,7 +299,8 @@ private:
         }
     }
 
-
+    // TODO: The quickselect code can probably be generalized and moved out
+    //       to psudb-common instead.
     size_t partition(size_t start, size_t stop, Wrapped<R> *p, gsl_rng *rng) {
         auto pivot = start + gsl_rng_uniform_int(rng, stop - start);
         double pivot_dist = p->rec.calc_distance(m_ptrs[pivot]->rec);
@@ -354,15 +319,15 @@ private:
         return j;
     }
 
-
     void swap(size_t idx1, size_t idx2) {
         auto tmp = m_ptrs[idx1];
         m_ptrs[idx1] = m_ptrs[idx2];
         m_ptrs[idx2] = tmp;
     }
 
+    void internal_search(vpnode *node, const R &point, size_t k, PriorityQueue<Wrapped<R>, 
+                DistCmpMax<Wrapped<R>>> &pq, double *farthest) {
 
-    void search(vpnode *node, const R &point, size_t k, PriorityQueue<Wrapped<R>, KNNDistCmpMax<Wrapped<R>>> &pq, double *farthest) {
         if (node == nullptr) return;
 
         if (node->leaf) {
@@ -398,151 +363,21 @@ private:
 
         if (d < node->radius) {
             if (d - (*farthest) <= node->radius) {
-                search(node->inside, point, k, pq, farthest);
+                internal_search(node->inside, point, k, pq, farthest);
             }
 
             if (d + (*farthest) >= node->radius) {
-                search(node->outside, point, k, pq, farthest);
+                internal_search(node->outside, point, k, pq, farthest);
             }
         } else {
             if (d + (*farthest) >= node->radius) {
-                search(node->outside, point, k, pq, farthest);
+                internal_search(node->outside, point, k, pq, farthest);
             }
 
             if (d - (*farthest) <= node->radius) {
-                search(node->inside, point, k, pq, farthest);
+                internal_search(node->inside, point, k, pq, farthest);
             }
         }
     }
-
-    Wrapped<R>* m_data;
-    Wrapped<R>** m_ptrs;
-    std::unordered_map<R, size_t, RecordHash<R>> m_lookup_map;
-    size_t m_reccnt;
-    size_t m_tombstone_cnt;
-    size_t m_node_cnt;
-    size_t m_alloc_size;
-
-    vpnode *m_root;
-};
-
-
-template <NDRecordInterface R>
-class KNNQuery {
-public:
-    constexpr static bool EARLY_ABORT=false;
-    constexpr static bool SKIP_DELETE_FILTER=true;
-
-    static void *get_query_state(VPTree<R> *wss, void *parms) {
-        return nullptr;
-    }
-
-    static void* get_buffer_query_state(MutableBuffer<R> *buffer, void *parms) {
-        return nullptr;
-    }
-
-    static void process_query_states(void *query_parms, std::vector<void*> &shard_states, void *buff_state) {
-        return;
-    }
-
-    static std::vector<Wrapped<R>> query(VPTree<R> *wss, void *q_state, void *parms) {
-        std::vector<Wrapped<R>> results;
-        KNNQueryParms<R> *p = (KNNQueryParms<R> *) parms;
-        Wrapped<R> wrec;
-        wrec.rec = p->point;
-        wrec.header = 0;
-
-        PriorityQueue<Wrapped<R>, KNNDistCmpMax<Wrapped<R>>> pq(p->k, &wrec);
-
-        double farthest = std::numeric_limits<double>::max();
-
-        wss->search(wss->m_root, p->point, p->k, pq, &farthest);
-
-        while (pq.size() > 0) {
-            results.emplace_back(*pq.peek().data);
-            pq.pop();
-        }
-
-        return results;
-    }
-
-    static std::vector<Wrapped<R>> buffer_query(MutableBuffer<R> *buffer, void *state, void *parms) {
-        KNNQueryParms<R> *p = (KNNQueryParms<R> *) parms;
-        Wrapped<R> wrec;
-        wrec.rec = p->point;
-        wrec.header = 0;
-
-        size_t k = p->k;
-
-        PriorityQueue<Wrapped<R>, KNNDistCmpMax<Wrapped<R>>> pq(k, &wrec);
-        for (size_t i=0; i<buffer->get_record_count(); i++) {
-            // Skip over deleted records (under tagging)
-            if ((buffer->get_data())[i].is_deleted()) {
-                continue;
-            }
-
-            if (pq.size() < k) {
-                pq.push(buffer->get_data() + i);
-            } else {
-                double head_dist = pq.peek().data->rec.calc_distance(wrec.rec);
-                double cur_dist = (buffer->get_data() + i)->rec.calc_distance(wrec.rec);
-
-                if (cur_dist < head_dist) {
-                    pq.pop();
-                    pq.push(buffer->get_data() + i);
-                }
-            }
-        }
-
-        std::vector<Wrapped<R>> results;
-        while (pq.size() > 0) {
-            results.emplace_back(*(pq.peek().data));
-            pq.pop();
-        }
-
-        return results;
-    }
-
-    static std::vector<R> merge(std::vector<std::vector<Wrapped<R>>> &results, void *parms) {
-        KNNQueryParms<R> *p = (KNNQueryParms<R> *) parms;
-        R rec = p->point;
-        size_t k = p->k;
-
-        PriorityQueue<R, KNNDistCmpMax<R>> pq(k, &rec);
-        for (size_t i=0; i<results.size(); i++) {
-            for (size_t j=0; j<results[i].size(); j++) {
-                if (pq.size() < k) {
-                    pq.push(&results[i][j].rec);
-                } else {
-                    double head_dist = pq.peek().data->calc_distance(rec);
-                    double cur_dist = results[i][j].rec.calc_distance(rec);
-
-                    if (cur_dist < head_dist) {
-                        pq.pop();
-                        pq.push(&results[i][j].rec);
-                    }
-                }
-            }
-        }
-
-        std::vector<R> output;
-        while (pq.size() > 0) {
-            output.emplace_back(*pq.peek().data);
-            pq.pop();
-        }
-
-        return output;
-    }
-
-    static void delete_query_state(void *state) {
-        auto s = (KNNState<R> *) state;
-        delete s;
-    }
-
-    static void delete_buffer_query_state(void *state) {
-        auto s = (KNNBufferState<R> *) state;
-        delete s;
-    }
-};
-
+   };
 }