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instrument.c
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1/*-------------------------------------------------------------------------
2 *
3 * instrument.c
4 * functions for instrumentation of plan execution
5 *
6 *
7 * Copyright (c) 2001-2024, PostgreSQL Global Development Group
8 *
9 * IDENTIFICATION
10 * src/backend/executor/instrument.c
11 *
12 *-------------------------------------------------------------------------
13 */
14#include "postgres.h"
15
16#include <unistd.h>
17
18#include "executor/instrument.h"
19
24
25static void BufferUsageAdd(BufferUsage *dst, const BufferUsage *add);
26static void WalUsageAdd(WalUsage *dst, WalUsage *add);
27
28
29/* Allocate new instrumentation structure(s) */
31InstrAlloc(int n, int instrument_options, bool async_mode)
32{
33 Instrumentation *instr;
34
35 /* initialize all fields to zeroes, then modify as needed */
36 instr = palloc0(n * sizeof(Instrumentation));
37 if (instrument_options & (INSTRUMENT_BUFFERS | INSTRUMENT_TIMER | INSTRUMENT_WAL))
38 {
39 bool need_buffers = (instrument_options & INSTRUMENT_BUFFERS) != 0;
40 bool need_wal = (instrument_options & INSTRUMENT_WAL) != 0;
41 bool need_timer = (instrument_options & INSTRUMENT_TIMER) != 0;
42 int i;
43
44 for (i = 0; i < n; i++)
45 {
46 instr[i].need_bufusage = need_buffers;
47 instr[i].need_walusage = need_wal;
48 instr[i].need_timer = need_timer;
49 instr[i].async_mode = async_mode;
50 }
51 }
52
53 return instr;
54}
55
56/* Initialize a pre-allocated instrumentation structure. */
57void
58InstrInit(Instrumentation *instr, int instrument_options)
59{
60 memset(instr, 0, sizeof(Instrumentation));
61 instr->need_bufusage = (instrument_options & INSTRUMENT_BUFFERS) != 0;
62 instr->need_walusage = (instrument_options & INSTRUMENT_WAL) != 0;
63 instr->need_timer = (instrument_options & INSTRUMENT_TIMER) != 0;
64}
65
66/* Entry to a plan node */
67void
69{
70 if (instr->need_timer &&
72 elog(ERROR, "InstrStartNode called twice in a row");
73
74 /* save buffer usage totals at node entry, if needed */
75 if (instr->need_bufusage)
77
78 if (instr->need_walusage)
80}
81
82/* Exit from a plan node */
83void
84InstrStopNode(Instrumentation *instr, double nTuples)
85{
86 double save_tuplecount = instr->tuplecount;
87 instr_time endtime;
88
89 /* count the returned tuples */
90 instr->tuplecount += nTuples;
91
92 /* let's update the time only if the timer was requested */
93 if (instr->need_timer)
94 {
95 if (INSTR_TIME_IS_ZERO(instr->starttime))
96 elog(ERROR, "InstrStopNode called without start");
97
99 INSTR_TIME_ACCUM_DIFF(instr->counter, endtime, instr->starttime);
100
102 }
103
104 /* Add delta of buffer usage since entry to node's totals */
105 if (instr->need_bufusage)
107 &pgBufferUsage, &instr->bufusage_start);
108
109 if (instr->need_walusage)
111 &pgWalUsage, &instr->walusage_start);
112
113 /* Is this the first tuple of this cycle? */
114 if (!instr->running)
115 {
116 instr->running = true;
118 }
119 else
120 {
121 /*
122 * In async mode, if the plan node hadn't emitted any tuples before,
123 * this might be the first tuple
124 */
125 if (instr->async_mode && save_tuplecount < 1.0)
127 }
128}
129
130/* Update tuple count */
131void
133{
134 /* count the returned tuples */
135 instr->tuplecount += nTuples;
136}
137
138/* Finish a run cycle for a plan node */
139void
141{
142 double totaltime;
143
144 /* Skip if nothing has happened, or already shut down */
145 if (!instr->running)
146 return;
147
148 if (!INSTR_TIME_IS_ZERO(instr->starttime))
149 elog(ERROR, "InstrEndLoop called on running node");
150
151 /* Accumulate per-cycle statistics into totals */
152 totaltime = INSTR_TIME_GET_DOUBLE(instr->counter);
153
154 instr->startup += instr->firsttuple;
155 instr->total += totaltime;
156 instr->ntuples += instr->tuplecount;
157 instr->nloops += 1;
158
159 /* Reset for next cycle (if any) */
160 instr->running = false;
163 instr->firsttuple = 0;
164 instr->tuplecount = 0;
165}
166
167/* aggregate instrumentation information */
168void
170{
171 if (!dst->running && add->running)
172 {
173 dst->running = true;
174 dst->firsttuple = add->firsttuple;
175 }
176 else if (dst->running && add->running && dst->firsttuple > add->firsttuple)
177 dst->firsttuple = add->firsttuple;
178
179 INSTR_TIME_ADD(dst->counter, add->counter);
180
181 dst->tuplecount += add->tuplecount;
182 dst->startup += add->startup;
183 dst->total += add->total;
184 dst->ntuples += add->ntuples;
185 dst->ntuples2 += add->ntuples2;
186 dst->nloops += add->nloops;
187 dst->nfiltered1 += add->nfiltered1;
188 dst->nfiltered2 += add->nfiltered2;
189
190 /* Add delta of buffer usage since entry to node's totals */
191 if (dst->need_bufusage)
192 BufferUsageAdd(&dst->bufusage, &add->bufusage);
193
194 if (dst->need_walusage)
195 WalUsageAdd(&dst->walusage, &add->walusage);
196}
197
198/* note current values during parallel executor startup */
199void
201{
204}
205
206/* report usage after parallel executor shutdown */
207void
209{
210 memset(bufusage, 0, sizeof(BufferUsage));
212 memset(walusage, 0, sizeof(WalUsage));
214}
215
216/* accumulate work done by workers in leader's stats */
217void
219{
220 BufferUsageAdd(&pgBufferUsage, bufusage);
221 WalUsageAdd(&pgWalUsage, walusage);
222}
223
224/* dst += add */
225static void
227{
228 dst->shared_blks_hit += add->shared_blks_hit;
232 dst->local_blks_hit += add->local_blks_hit;
233 dst->local_blks_read += add->local_blks_read;
236 dst->temp_blks_read += add->temp_blks_read;
244}
245
246/* dst += add - sub */
247void
249 const BufferUsage *add,
250 const BufferUsage *sub)
251{
256 dst->local_blks_hit += add->local_blks_hit - sub->local_blks_hit;
260 dst->temp_blks_read += add->temp_blks_read - sub->temp_blks_read;
274}
275
276/* helper functions for WAL usage accumulation */
277static void
279{
280 dst->wal_bytes += add->wal_bytes;
281 dst->wal_records += add->wal_records;
282 dst->wal_fpi += add->wal_fpi;
283}
284
285void
286WalUsageAccumDiff(WalUsage *dst, const WalUsage *add, const WalUsage *sub)
287{
288 dst->wal_bytes += add->wal_bytes - sub->wal_bytes;
289 dst->wal_records += add->wal_records - sub->wal_records;
290 dst->wal_fpi += add->wal_fpi - sub->wal_fpi;
291}
#define ERROR
Definition: elog.h:39
#define elog(elevel,...)
Definition: elog.h:225
#define INSTR_TIME_SET_CURRENT(t)
Definition: instr_time.h:122
#define INSTR_TIME_ADD(x, y)
Definition: instr_time.h:178
#define INSTR_TIME_IS_ZERO(t)
Definition: instr_time.h:169
#define INSTR_TIME_GET_DOUBLE(t)
Definition: instr_time.h:188
#define INSTR_TIME_SET_CURRENT_LAZY(t)
Definition: instr_time.h:174
#define INSTR_TIME_SET_ZERO(t)
Definition: instr_time.h:172
#define INSTR_TIME_ACCUM_DIFF(x, y, z)
Definition: instr_time.h:184
void InstrUpdateTupleCount(Instrumentation *instr, double nTuples)
Definition: instrument.c:132
void InstrAccumParallelQuery(BufferUsage *bufusage, WalUsage *walusage)
Definition: instrument.c:218
void InstrEndLoop(Instrumentation *instr)
Definition: instrument.c:140
Instrumentation * InstrAlloc(int n, int instrument_options, bool async_mode)
Definition: instrument.c:31
static void BufferUsageAdd(BufferUsage *dst, const BufferUsage *add)
Definition: instrument.c:226
void InstrAggNode(Instrumentation *dst, Instrumentation *add)
Definition: instrument.c:169
static BufferUsage save_pgBufferUsage
Definition: instrument.c:21
void InstrEndParallelQuery(BufferUsage *bufusage, WalUsage *walusage)
Definition: instrument.c:208
static WalUsage save_pgWalUsage
Definition: instrument.c:23
static void WalUsageAdd(WalUsage *dst, WalUsage *add)
Definition: instrument.c:278
WalUsage pgWalUsage
Definition: instrument.c:22
void WalUsageAccumDiff(WalUsage *dst, const WalUsage *add, const WalUsage *sub)
Definition: instrument.c:286
void InstrStartParallelQuery(void)
Definition: instrument.c:200
BufferUsage pgBufferUsage
Definition: instrument.c:20
void InstrInit(Instrumentation *instr, int instrument_options)
Definition: instrument.c:58
void BufferUsageAccumDiff(BufferUsage *dst, const BufferUsage *add, const BufferUsage *sub)
Definition: instrument.c:248
void InstrStartNode(Instrumentation *instr)
Definition: instrument.c:68
void InstrStopNode(Instrumentation *instr, double nTuples)
Definition: instrument.c:84
@ INSTRUMENT_TIMER
Definition: instrument.h:61
@ INSTRUMENT_BUFFERS
Definition: instrument.h:62
@ INSTRUMENT_WAL
Definition: instrument.h:64
int i
Definition: isn.c:72
void * palloc0(Size size)
Definition: mcxt.c:1347
instr_time local_blk_read_time
Definition: instrument.h:38
int64 shared_blks_dirtied
Definition: instrument.h:28
int64 local_blks_hit
Definition: instrument.h:30
instr_time temp_blk_write_time
Definition: instrument.h:41
instr_time shared_blk_read_time
Definition: instrument.h:36
instr_time shared_blk_write_time
Definition: instrument.h:37
int64 local_blks_written
Definition: instrument.h:33
instr_time temp_blk_read_time
Definition: instrument.h:40
instr_time local_blk_write_time
Definition: instrument.h:39
int64 temp_blks_read
Definition: instrument.h:34
int64 shared_blks_read
Definition: instrument.h:27
int64 shared_blks_written
Definition: instrument.h:29
int64 temp_blks_written
Definition: instrument.h:35
int64 local_blks_read
Definition: instrument.h:31
int64 local_blks_dirtied
Definition: instrument.h:32
int64 shared_blks_hit
Definition: instrument.h:26
double nfiltered2
Definition: instrument.h:90
BufferUsage bufusage_start
Definition: instrument.h:81
double nfiltered1
Definition: instrument.h:89
double startup
Definition: instrument.h:84
WalUsage walusage
Definition: instrument.h:92
bool need_bufusage
Definition: instrument.h:72
double ntuples
Definition: instrument.h:86
BufferUsage bufusage
Definition: instrument.h:91
bool need_walusage
Definition: instrument.h:73
instr_time starttime
Definition: instrument.h:77
instr_time counter
Definition: instrument.h:78
WalUsage walusage_start
Definition: instrument.h:82
double firsttuple
Definition: instrument.h:79
double ntuples2
Definition: instrument.h:87
double tuplecount
Definition: instrument.h:80
uint64 wal_bytes
Definition: instrument.h:55
int64 wal_fpi
Definition: instrument.h:54
int64 wal_records
Definition: instrument.h:53