StatHist.cc
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1/*
2 * Copyright (C) 1996-2022 The Squid Software Foundation and contributors
3 *
4 * Squid software is distributed under GPLv2+ license and includes
5 * contributions from numerous individuals and organizations.
6 * Please see the COPYING and CONTRIBUTORS files for details.
7 */
8
9#include "squid.h"
10#include "StatHist.h"
11
12#include <cmath>
13
14/* Local functions */
16
17namespace Math
18{
22};
23
24/* low level init, higher level functions has less params */
25void
26StatHist::init(unsigned int newCapacity, hbase_f * val_in_, hbase_f * val_out_, double newMin, double newMax)
27{
28 /* check before we divide to get scale_ */
29 assert(val_in_(newMax - newMin) > 0);
30 min_ = newMin;
31 max_ = newMax;
32 capacity_ = newCapacity;
33 val_in = val_in_;
34 val_out = val_out_;
35 bins = static_cast<bins_type *>(xcalloc(capacity_, sizeof(bins_type)));
37}
38
40 bins(nullptr),
41 capacity_(src.capacity_),
42 min_(src.min_),
43 max_(src.max_),
44 scale_(src.scale_),
45 val_in(src.val_in),
46 val_out(src.val_out)
47{
48 if (src.bins!=nullptr) {
49 bins = static_cast<bins_type *>(xcalloc(src.capacity_, sizeof(bins_type)));
50 memcpy(bins,src.bins,capacity_*sizeof(*bins));
51 }
52}
53
54void
56{
57 if (bins==nullptr) //do not count before initialization or after destruction
58 return;
59 const unsigned int bin = findBin(v);
60 ++bins[bin];
61}
62
63unsigned int
65{
66 v -= min_; /* offset */
67
68 if (v <= 0.0) /* too small */
69 return 0;
70
71 unsigned int bin;
72 double tmp_bin=floor(scale_ * val_in(v) + 0.5);
73
74 if (tmp_bin < 0.0) // should not happen
75 return 0;
76 bin = static_cast <unsigned int>(tmp_bin);
77
78 if (bin >= capacity_) /* too big */
79 bin = capacity_ - 1;
80
81 return bin;
82}
83
84double
85StatHist::val(unsigned int bin) const
86{
87 return val_out((double) bin / scale_) + min_;
88}
89
90double
92{
93 return statHistDeltaPctile(A, B, 0.5);
94}
95
96double
97statHistDeltaPctile(const StatHist & A, const StatHist & B, double pctile)
98{
99 return A.deltaPctile(B, pctile);
100}
101
102double
103StatHist::deltaPctile(const StatHist & B, double pctile) const
104{
105 unsigned int i;
106 bins_type s1 = 0;
107 bins_type h = 0;
108 bins_type a = 0;
109 bins_type b = 0;
110 unsigned int I = 0;
111 unsigned int J = capacity_;
112 unsigned int K;
113 double f;
114
115 assert(capacity_ == B.capacity_);
116
117 int *D = static_cast<int *>(xcalloc(capacity_, sizeof(int)));
118
119 for (i = 0; i < capacity_; ++i) {
120 D[i] = B.bins[i] - bins[i];
121 assert(D[i] >= 0);
122 }
123
124 for (i = 0; i < capacity_; ++i)
125 s1 += D[i];
126
127 h = int(s1 * pctile);
128
129 for (i = 0; i < capacity_; ++i) {
130 J = i;
131 b += D[J];
132
133 if (a <= h && h <= b)
134 break;
135
136 I = i;
137
138 a += D[I];
139 }
140
141 xfree(D);
142
143 if (s1 == 0)
144 return 0.0;
145
146 if (a > h)
147 return 0.0;
148
149 if (a >= b)
150 return 0.0;
151
152 if (I >= J)
153 return 0.0;
154
155 f = (h - a) / (b - a);
156
157 K = (unsigned int) floor(f * (double) (J - I) + I);
158
159 return val(K);
160}
161
162static void
163statHistBinDumper(StoreEntry * sentry, int idx, double val, double size, int count)
164{
165 if (count)
166 storeAppendPrintf(sentry, "\t%3d/%f\t%d\t%f\n",
167 idx, val, count, count / size);
168}
169
170void
172{
173 double left_border = min_;
174
175 if (!bd)
177
178 for (unsigned int i = 0; i < capacity_; ++i) {
179 const double right_border = val(i + 1);
180 assert(right_border - left_border > 0.0);
181 bd(sentry, i, left_border, right_border - left_border, bins[i]);
182 left_border = right_border;
183 }
184}
185
186StatHist &
188{
189 Must(capacity_ == B.capacity_);
190 Must(min_ == B.min_);
191 Must(max_ == B.max_);
192
193 if (B.bins == nullptr) { // B was not yet initializted
194 return *this;
195 }
196 if (bins == nullptr) { // this histogram was not yet initialized
197 *this = B;
198 return *this;
199 }
200 for (unsigned int i = 0; i < capacity_; ++i) {
201 bins[i] += B.bins[i];
202 }
203 return *this;
204}
205
206/* log based histogram */
207double
208Math::Log(double x)
209{
210 assert((x + 1.0) >= 0.0);
211 return log(x + 1.0);
212}
213
214double
215Math::Exp(double x)
216{
217 return exp(x) - 1.0;
218}
219
220void
221StatHist::logInit(unsigned int capacity, double min, double max)
222{
223 init(capacity, Math::Log, Math::Exp, min, max);
224}
225
226/* linear histogram for enums */
227/* we want to be have [-1,last_enum+1] range to track out of range enums */
228double
229Math::Null(double x)
230{
231 return x;
232}
233
234void
235StatHist::enumInit(unsigned int last_enum)
236{
237 init(last_enum + 3, Math::Null, Math::Null, -1.0, (2.0 + last_enum));
238}
239
240void
241statHistEnumDumper(StoreEntry * sentry, int idx, double val, double, int count)
242{
243 if (count)
244 storeAppendPrintf(sentry, "%2d\t %5d\t %5d\n",
245 idx, (int) val, count);
246}
247
248void
249statHistIntDumper(StoreEntry * sentry, int, double val, double, int count)
250{
251 if (count)
252 storeAppendPrintf(sentry, "%9d\t%9d\n", (int) val, count);
253}
254
int size
Definition: ModDevPoll.cc:75
static StatHistBinDumper statHistBinDumper
Definition: StatHist.cc:15
void statHistIntDumper(StoreEntry *sentry, int, double val, double, int count)
Definition: StatHist.cc:249
void statHistEnumDumper(StoreEntry *sentry, int idx, double val, double, int count)
Definition: StatHist.cc:241
double statHistDeltaMedian(const StatHist &A, const StatHist &B)
Definition: StatHist.cc:91
double statHistDeltaPctile(const StatHist &A, const StatHist &B, double pctile)
Definition: StatHist.cc:97
void StatHistBinDumper(StoreEntry *, int idx, double val, double size, int count)
function signature for StatHist dumping functions
Definition: StatHist.h:19
double hbase_f(double)
function signature for in/out StatHist adaptation
Definition: StatHist.h:16
#define Must(condition)
Definition: TextException.h:71
void log(char *format,...)
#define assert(EX)
Definition: assert.h:19
@ s1
Definition: cf_gen.cc:55
double deltaPctile(const StatHist &B, double pctile) const
Definition: StatHist.cc:103
double val(unsigned int bin) const
Definition: StatHist.cc:85
uint64_t bins_type
Definition: StatHist.h:44
hbase_f * val_in
Definition: StatHist.h:112
double max_
value of the maximum counter in the histogram
Definition: StatHist.h:108
double scale_
scaling factor when looking for a bin
Definition: StatHist.h:111
void logInit(unsigned int capacity, double min, double max)
Definition: StatHist.cc:221
unsigned int capacity_
Definition: StatHist.h:102
unsigned int findBin(double v)
Definition: StatHist.cc:64
bins_type * bins
the histogram counters
Definition: StatHist.h:101
void init(unsigned int capacity, hbase_f *val_in, hbase_f *val_out, double min, double max)
Definition: StatHist.cc:26
void enumInit(unsigned int last_enum)
Definition: StatHist.cc:235
void count(double val)
Definition: StatHist.cc:55
double min_
minimum value to be stored, corresponding to the first bin
Definition: StatHist.h:105
StatHist()=default
void dump(StoreEntry *sentry, StatHistBinDumper *bd) const
Definition: StatHist.cc:171
StatHist & operator+=(const StatHist &B)
Definition: StatHist.cc:187
hbase_f * val_out
Definition: StatHist.h:113
A const & max(A const &lhs, A const &rhs)
A const & min(A const &lhs, A const &rhs)
static uint32 A
Definition: md4.c:43
static uint32 D
Definition: md4.c:43
static uint32 B
Definition: md4.c:43
Definition: SquidMath.h:22
hbase_f Exp
Definition: StatHist.cc:20
hbase_f Null
Definition: StatHist.cc:21
hbase_f Log
Definition: StatHist.cc:19
#define xfree
void storeAppendPrintf(StoreEntry *e, const char *fmt,...)
Definition: store.cc:828
int unsigned int
Definition: stub_fd.cc:19
void * xcalloc(size_t n, size_t sz)
Definition: xalloc.cc:71

 

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