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middle version

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This commit is contained in:
tqchen
2014-10-16 10:38:49 -07:00
parent 6680bffaae
commit aefe58a207
8 changed files with 188 additions and 64 deletions
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14
src/tree/model.h
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@@ -110,6 +110,10 @@ class TreeModel {
inline bool is_left_child(void) const {
return (parent_ & (1U << 31)) != 0;
}
/*! \brief whether this node is deleted */
inline bool is_deleted(void) const {
return sindex_ == std::numeric_limits<unsigned>::max();
}
/*! \brief whether current node is root */
inline bool is_root(void) const {
return parent_ == -1;
@@ -144,7 +148,11 @@ class TreeModel {
this->cleft_ = -1;
this->cright_ = right;
}
/*! \brief mark that this node is deleted */
inline void mark_delete(void) {
this->sindex_ = std::numeric_limits<unsigned>::max();
}
private:
friend class TreeModel<TSplitCond, TNodeStat>;
/*!
@@ -197,11 +205,11 @@ class TreeModel {
leaf_vector.resize(param.num_nodes * param.size_leaf_vector);
return nd;
}
// delete a tree node
// delete a tree node, keep the parent field to allow trace back
inline void DeleteNode(int nid) {
utils::Assert(nid >= param.num_roots, "can not delete root");
deleted_nodes.push_back(nid);
nodes[nid].set_parent(-1);
nodes[nid].mark_delete();
++param.num_deleted;
}

4
src/tree/param.h
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@@ -345,6 +345,10 @@ struct SplitEntry{
return false;
}
}
/*! \brief same as update, used by AllReduce*/
inline void Reduce(const SplitEntry &e) {
this->Update(e);
}
/*!\return feature index to split on */
inline unsigned split_index(void) const {
return sindex & ((1U << 31) - 1U);

19
src/tree/updater_colmaker-inl.hpp
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@@ -486,13 +486,17 @@ class ColMaker: public IUpdater {
#pragma omp parallel for schedule(static)
for (bst_omp_uint i = 0; i < ndata; ++i) {
const bst_uint ridx = rowset[i];
const int nid = position[ridx];
if (nid >= 0) {
if (tree[nid].is_leaf()) {
position[ridx] = - nid - 1;
int nid = position[ridx];
if (nid < 0) nid = ~nid;
if (tree[nid].is_leaf()) {
position[ridx] = ~nid;
} else {
// push to default branch, correct latter
int pid = tree[nid].default_left() ? tree[nid].cleft(): tree[nid].cright();
if (position[ridx] < 0) {
position[ridx] = ~pid;
} else {
// push to default branch, correct latter
position[ridx] = tree[nid].default_left() ? tree[nid].cleft(): tree[nid].cright();
position[ridx] = pid;
}
}
}
@@ -535,7 +539,8 @@ class ColMaker: public IUpdater {
const bst_uint ridx = col[j].index;
const float fvalue = col[j].fvalue;
int nid = position[ridx];
if (nid < 0) continue;
if (nid < 0) nid = ~nid;
// go back to parent, correct those who are not default
nid = tree[nid].parent();
if (tree[nid].split_index() == fid) {

53
src/tree/updater_distcol-inl.hpp
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@@ -7,7 +7,10 @@
* \author Tianqi Chen
*/
#include "../utils/bitmap.h"
#include "../utils/io.h"
#include "../sync/sync.h"
#include "./updater_colmaker-inl.hpp"
#include "./updater_prune-inl.hpp"
namespace xgboost {
namespace tree {
@@ -19,6 +22,7 @@ class DistColMaker : public ColMaker<TStats> {
// set training parameter
virtual void SetParam(const char *name, const char *val) {
param.SetParam(name, val);
pruner.SetParam(name, val);
}
virtual void Update(const std::vector<bst_gpair> &gpair,
IFMatrix *p_fmat,
@@ -26,15 +30,46 @@ class DistColMaker : public ColMaker<TStats> {
const std::vector<RegTree*> &trees) {
TStats::CheckInfo(info);
utils::Check(trees.size() == 1, "DistColMaker: only support one tree at a time");
// build the tree
builder.Update(gpair, p_fmat, info, trees[0]);
// prune the tree
pruner.Update(gpair, p_fmat, info, trees);
this->SyncTrees(trees[0]);
// update position after the tree is pruned
builder.UpdatePosition(p_fmat, *trees[0]);
}
private:
inline void SyncTrees(RegTree *tree) {
std::string s_model;
utils::MemoryBufferStream fs(&s_model);
int rank = sync::GetRank();
if (rank == 0) {
tree->SaveModel(fs);
sync::Bcast(&s_model, 0);
} else {
sync::Bcast(&s_model, 0);
tree->LoadModel(fs);
}
}
struct Builder : public ColMaker<TStats>::Builder {
public:
Builder(const TrainParam &param)
: ColMaker<TStats>::Builder(param) {
}
protected:
inline void UpdatePosition(IFMatrix *p_fmat, const RegTree &tree) {
const std::vector<bst_uint> &rowset = p_fmat->buffered_rowset();
const bst_omp_uint ndata = static_cast<bst_omp_uint>(rowset.size());
#pragma omp parallel for schedule(static)
for (bst_omp_uint i = 0; i < ndata; ++i) {
const bst_uint ridx = rowset[i];
int nid = this->position[ridx];
if (nid < 0) {
}
}
}
protected:
virtual void SetNonDefaultPosition(const std::vector<int> &qexpand,
IFMatrix *p_fmat, const RegTree &tree) {
// step 2, classify the non-default data into right places
@@ -80,8 +115,8 @@ class DistColMaker : public ColMaker<TStats> {
}
}
// communicate bitmap
//sync::AllReduce();
const std::vector<bst_uint> &rowset = p_fmat->buffered_rowset();
sync::AllReduce(BeginPtr(bitmap.data), bitmap.data.size(), sync::kBitwiseOR);
const std::vector<bst_uint> &rowset = p_fmat->buffered_rowset();
// get the new position
const bst_omp_uint ndata = static_cast<bst_omp_uint>(rowset.size());
#pragma omp parallel for schedule(static)
@@ -100,19 +135,29 @@ class DistColMaker : public ColMaker<TStats> {
}
// synchronize the best solution of each node
virtual void SyncBestSolution(const std::vector<int> &qexpand) {
std::vector<SplitEntry> vec;
for (size_t i = 0; i < qexpand.size(); ++i) {
const int nid = qexpand[i];
for (int tid = 0; tid < this->nthread; ++tid) {
this->snode[nid].best.Update(this->stemp[tid][nid].best);
}
vec.push_back(this->snode[nid].best);
}
// communicate best solution
// sync::AllReduce
reducer.AllReduce(BeginPtr(vec), vec.size());
// assign solution back
for (size_t i = 0; i < qexpand.size(); ++i) {
const int nid = qexpand[i];
this->snode[nid].best = vec[i];
}
}
private:
utils::BitMap bitmap;
sync::Reducer<SplitEntry> reducer;
};
// we directly introduce pruner here
TreePruner pruner;
// training parameter
TrainParam param;
// pointer to the builder