summaryrefslogtreecommitdiffstats
path: root/ml/Dimension.cc
blob: 290d4c7439c5e6e9ac61edb3137cb108f36a300a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
// SPDX-License-Identifier: GPL-3.0-or-later

#include "Config.h"
#include "Dimension.h"
#include "Query.h"

using namespace ml;

/*
 * Copy of the unpack_storage_number which allows us to convert
 * a storage_number to double.
 */
static CalculatedNumber unpack_storage_number_dbl(storage_number value) {
    if(!value)
        return 0;

    int sign = 0, exp = 0;
    int factor = 10;

    // bit 32 = 0:positive, 1:negative
    if(unlikely(value & (1 << 31)))
        sign = 1;

    // bit 31 = 0:divide, 1:multiply
    if(unlikely(value & (1 << 30)))
        exp = 1;

    // bit 27 SN_EXISTS_100
    if(unlikely(value & (1 << 26)))
        factor = 100;

    // bit 26 SN_EXISTS_RESET
    // bit 25 SN_ANOMALY_BIT

    // bit 30, 29, 28 = (multiplier or divider) 0-7 (8 total)
    int mul = (value & ((1<<29)|(1<<28)|(1<<27))) >> 27;

    // bit 24 to bit 1 = the value, so remove all other bits
    value ^= value & ((1<<31)|(1<<30)|(1<<29)|(1<<28)|(1<<27)|(1<<26)|(1<<25)|(1<<24));

    CalculatedNumber CN = value;

    if(exp) {
        for(; mul; mul--)
            CN *= factor;
    }
    else {
        for( ; mul ; mul--)
            CN /= 10;
    }

    if(sign)
        CN = -CN;

    return CN;
}

std::pair<CalculatedNumber *, size_t>
TrainableDimension::getCalculatedNumbers() {
    size_t MinN = Cfg.MinTrainSamples;
    size_t MaxN = Cfg.MaxTrainSamples;

    // Figure out what our time window should be.
    time_t BeforeT = now_realtime_sec() - 1;
    time_t AfterT = BeforeT - (MaxN * updateEvery());

    BeforeT -= (BeforeT % updateEvery());
    AfterT -= (AfterT % updateEvery());

    BeforeT = std::min(BeforeT, latestTime());
    AfterT = std::max(AfterT, oldestTime());

    if (AfterT >= BeforeT)
        return { nullptr, 0 };

    CalculatedNumber *CNs = new CalculatedNumber[MaxN * (Cfg.LagN + 1)]();

    // Start the query.
    unsigned Idx = 0;
    unsigned CollectedValues = 0;
    unsigned TotalValues = 0;

    CalculatedNumber LastValue = std::numeric_limits<CalculatedNumber>::quiet_NaN();
    Query Q = Query(getRD());

    Q.init(AfterT, BeforeT);
    while (!Q.isFinished()) {
        if (Idx == MaxN)
            break;

        auto P = Q.nextMetric();
        storage_number SN = P.second;

        if (does_storage_number_exist(SN)) {
            CNs[Idx] = unpack_storage_number_dbl(SN);
            LastValue = CNs[Idx];
            CollectedValues++;
        } else
            CNs[Idx] = LastValue;

        Idx++;
    }
    TotalValues = Idx;

    if (CollectedValues < MinN) {
        delete[] CNs;
        return { nullptr, 0 };
    }

    // Find first non-NaN value.
    for (Idx = 0; std::isnan(CNs[Idx]); Idx++, TotalValues--) { }

    // Overwrite NaN values.
    if (Idx != 0)
        memmove(CNs, &CNs[Idx], sizeof(CalculatedNumber) * TotalValues);

    return { CNs, TotalValues };
}

MLResult TrainableDimension::trainModel() {
    auto P = getCalculatedNumbers();
    CalculatedNumber *CNs = P.first;
    unsigned N = P.second;

    if (!CNs)
        return MLResult::MissingData;

    unsigned TargetNumSamples = Cfg.MaxTrainSamples * Cfg.RandomSamplingRatio;
    double SamplingRatio = std::min(static_cast<double>(TargetNumSamples) / N, 1.0);

    SamplesBuffer SB = SamplesBuffer(CNs, N, 1, Cfg.DiffN, Cfg.SmoothN, Cfg.LagN,
                                     SamplingRatio, Cfg.RandomNums);
    KM.train(SB, Cfg.MaxKMeansIters);

    Trained = true;
    ConstantModel = true;

    delete[] CNs;
    return MLResult::Success;
}

void PredictableDimension::addValue(CalculatedNumber Value, bool Exists) {
    if (!Exists) {
        CNs.clear();
        return;
    }

    unsigned N = Cfg.DiffN + Cfg.SmoothN + Cfg.LagN;
    if (CNs.size() < N) {
        CNs.push_back(Value);
        return;
    }

    std::rotate(std::begin(CNs), std::begin(CNs) + 1, std::end(CNs));

    if (CNs[N - 1] != Value)
        ConstantModel = false;

    CNs[N - 1] = Value;
}

std::pair<MLResult, bool> PredictableDimension::predict() {
    unsigned N = Cfg.DiffN + Cfg.SmoothN + Cfg.LagN;
    if (CNs.size() != N)
        return { MLResult::MissingData, AnomalyBit };

    CalculatedNumber *TmpCNs = new CalculatedNumber[N * (Cfg.LagN + 1)]();
    std::memcpy(TmpCNs, CNs.data(), N * sizeof(CalculatedNumber));

    SamplesBuffer SB = SamplesBuffer(TmpCNs, N, 1, Cfg.DiffN, Cfg.SmoothN, Cfg.LagN,
                                     1.0, Cfg.RandomNums);
    AnomalyScore = computeAnomalyScore(SB);
    delete[] TmpCNs;

    if (AnomalyScore == std::numeric_limits<CalculatedNumber>::quiet_NaN())
        return { MLResult::NaN, AnomalyBit };

    AnomalyBit = AnomalyScore >= (100 * Cfg.DimensionAnomalyScoreThreshold);
    return { MLResult::Success, AnomalyBit };
}