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mcxtfuncs.c File Reference
#include "postgres.h"
#include "funcapi.h"
#include "mb/pg_wchar.h"
#include "storage/proc.h"
#include "storage/procarray.h"
#include "utils/array.h"
#include "utils/builtins.h"
#include "utils/hsearch.h"
Include dependency graph for mcxtfuncs.c:

Go to the source code of this file.

Data Structures

struct  MemoryContextId
 

Macros

#define MEMORY_CONTEXT_IDENT_DISPLAY_SIZE   1024
 
#define PG_GET_BACKEND_MEMORY_CONTEXTS_COLS   10
 

Typedefs

typedef struct MemoryContextId MemoryContextId
 

Functions

static Datum int_list_to_array (const List *list)
 
static void PutMemoryContextsStatsTupleStore (Tuplestorestate *tupstore, TupleDesc tupdesc, MemoryContext context, HTAB *context_id_lookup)
 
Datum pg_get_backend_memory_contexts (PG_FUNCTION_ARGS)
 
Datum pg_log_backend_memory_contexts (PG_FUNCTION_ARGS)
 

Macro Definition Documentation

◆ MEMORY_CONTEXT_IDENT_DISPLAY_SIZE

#define MEMORY_CONTEXT_IDENT_DISPLAY_SIZE   1024

Definition at line 30 of file mcxtfuncs.c.

◆ PG_GET_BACKEND_MEMORY_CONTEXTS_COLS

#define PG_GET_BACKEND_MEMORY_CONTEXTS_COLS   10

Typedef Documentation

◆ MemoryContextId

Function Documentation

◆ int_list_to_array()

static Datum int_list_to_array ( const List list)
static

Definition at line 48 of file mcxtfuncs.c.

49{
50 Datum *datum_array;
51 int length;
52 ArrayType *result_array;
53
54 length = list_length(list);
55 datum_array = (Datum *) palloc(length * sizeof(Datum));
56
58 datum_array[foreach_current_index(i)] = Int32GetDatum(i);
59
60 result_array = construct_array_builtin(datum_array, length, INT4OID);
61
62 return PointerGetDatum(result_array);
63}
ArrayType * construct_array_builtin(Datum *elems, int nelems, Oid elmtype)
Definition: arrayfuncs.c:3381
int i
Definition: isn.c:72
void * palloc(Size size)
Definition: mcxt.c:1317
static int list_length(const List *l)
Definition: pg_list.h:152
#define foreach_current_index(var_or_cell)
Definition: pg_list.h:403
#define foreach_int(var, lst)
Definition: pg_list.h:470
static Datum PointerGetDatum(const void *X)
Definition: postgres.h:327
uintptr_t Datum
Definition: postgres.h:69
static Datum Int32GetDatum(int32 X)
Definition: postgres.h:217

References construct_array_builtin(), foreach_current_index, foreach_int, i, Int32GetDatum(), sort-test::list, list_length(), palloc(), and PointerGetDatum().

Referenced by PutMemoryContextsStatsTupleStore().

◆ pg_get_backend_memory_contexts()

Datum pg_get_backend_memory_contexts ( PG_FUNCTION_ARGS  )

Definition at line 183 of file mcxtfuncs.c.

184{
185 ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
186 int context_id;
187 List *contexts;
188 HASHCTL ctl;
189 HTAB *context_id_lookup;
190
191 ctl.keysize = sizeof(MemoryContext);
192 ctl.entrysize = sizeof(MemoryContextId);
194
195 context_id_lookup = hash_create("pg_get_backend_memory_contexts",
196 256,
197 &ctl,
199
200 InitMaterializedSRF(fcinfo, 0);
201
202 /*
203 * Here we use a non-recursive algorithm to visit all MemoryContexts
204 * starting with TopMemoryContext. The reason we avoid using a recursive
205 * algorithm is because we want to assign the context_id breadth-first.
206 * I.e. all contexts at level 1 are assigned IDs before contexts at level
207 * 2. Because contexts closer to TopMemoryContext are less likely to
208 * change, this makes the assigned context_id more stable. Otherwise, if
209 * the first child of TopMemoryContext obtained an additional grandchild,
210 * the context_id for the second child of TopMemoryContext would change.
211 */
212 contexts = list_make1(TopMemoryContext);
213
214 /* TopMemoryContext will always have a context_id of 1 */
215 context_id = 1;
216
218 {
219 MemoryContextId *entry;
220 bool found;
221
222 /*
223 * Record the context_id that we've assigned to each MemoryContext.
224 * PutMemoryContextsStatsTupleStore needs this to populate the "path"
225 * column with the parent context_ids.
226 */
227 entry = (MemoryContextId *) hash_search(context_id_lookup, &cur,
228 HASH_ENTER, &found);
229 entry->context_id = context_id++;
230 Assert(!found);
231
233 rsinfo->setDesc,
234 cur,
235 context_id_lookup);
236
237 /*
238 * Append all children onto the contexts list so they're processed by
239 * subsequent iterations.
240 */
241 for (MemoryContext c = cur->firstchild; c != NULL; c = c->nextchild)
242 contexts = lappend(contexts, c);
243 }
244
245 hash_destroy(context_id_lookup);
246
247 return (Datum) 0;
248}
#define Assert(condition)
Definition: c.h:815
void * hash_search(HTAB *hashp, const void *keyPtr, HASHACTION action, bool *foundPtr)
Definition: dynahash.c:955
void hash_destroy(HTAB *hashp)
Definition: dynahash.c:865
HTAB * hash_create(const char *tabname, long nelem, const HASHCTL *info, int flags)
Definition: dynahash.c:352
struct cursor * cur
Definition: ecpg.c:29
void InitMaterializedSRF(FunctionCallInfo fcinfo, bits32 flags)
Definition: funcapi.c:76
@ HASH_ENTER
Definition: hsearch.h:114
#define HASH_CONTEXT
Definition: hsearch.h:102
#define HASH_ELEM
Definition: hsearch.h:95
#define HASH_BLOBS
Definition: hsearch.h:97
List * lappend(List *list, void *datum)
Definition: list.c:339
MemoryContext TopMemoryContext
Definition: mcxt.c:149
MemoryContext CurrentMemoryContext
Definition: mcxt.c:143
struct MemoryContextId MemoryContextId
static void PutMemoryContextsStatsTupleStore(Tuplestorestate *tupstore, TupleDesc tupdesc, MemoryContext context, HTAB *context_id_lookup)
Definition: mcxtfuncs.c:70
#define list_make1(x1)
Definition: pg_list.h:212
#define foreach_ptr(type, var, lst)
Definition: pg_list.h:469
char * c
tree ctl
Definition: radixtree.h:1838
Definition: dynahash.c:220
Definition: pg_list.h:54
TupleDesc setDesc
Definition: execnodes.h:358
Tuplestorestate * setResult
Definition: execnodes.h:357

References Assert, MemoryContextId::context_id, ctl, cur, CurrentMemoryContext, foreach_ptr, HASH_BLOBS, HASH_CONTEXT, hash_create(), hash_destroy(), HASH_ELEM, HASH_ENTER, hash_search(), InitMaterializedSRF(), lappend(), list_make1, PutMemoryContextsStatsTupleStore(), ReturnSetInfo::setDesc, ReturnSetInfo::setResult, and TopMemoryContext.

◆ pg_log_backend_memory_contexts()

Datum pg_log_backend_memory_contexts ( PG_FUNCTION_ARGS  )

Definition at line 264 of file mcxtfuncs.c.

265{
266 int pid = PG_GETARG_INT32(0);
267 PGPROC *proc;
268 ProcNumber procNumber = INVALID_PROC_NUMBER;
269
270 /*
271 * See if the process with given pid is a backend or an auxiliary process.
272 */
273 proc = BackendPidGetProc(pid);
274 if (proc == NULL)
275 proc = AuxiliaryPidGetProc(pid);
276
277 /*
278 * BackendPidGetProc() and AuxiliaryPidGetProc() return NULL if the pid
279 * isn't valid; but by the time we reach kill(), a process for which we
280 * get a valid proc here might have terminated on its own. There's no way
281 * to acquire a lock on an arbitrary process to prevent that. But since
282 * this mechanism is usually used to debug a backend or an auxiliary
283 * process running and consuming lots of memory, that it might end on its
284 * own first and its memory contexts are not logged is not a problem.
285 */
286 if (proc == NULL)
287 {
288 /*
289 * This is just a warning so a loop-through-resultset will not abort
290 * if one backend terminated on its own during the run.
291 */
293 (errmsg("PID %d is not a PostgreSQL server process", pid)));
294 PG_RETURN_BOOL(false);
295 }
296
297 procNumber = GetNumberFromPGProc(proc);
298 if (SendProcSignal(pid, PROCSIG_LOG_MEMORY_CONTEXT, procNumber) < 0)
299 {
300 /* Again, just a warning to allow loops */
302 (errmsg("could not send signal to process %d: %m", pid)));
303 PG_RETURN_BOOL(false);
304 }
305
306 PG_RETURN_BOOL(true);
307}
int errmsg(const char *fmt,...)
Definition: elog.c:1070
#define WARNING
Definition: elog.h:36
#define ereport(elevel,...)
Definition: elog.h:149
#define PG_GETARG_INT32(n)
Definition: fmgr.h:269
#define PG_RETURN_BOOL(x)
Definition: fmgr.h:359
#define GetNumberFromPGProc(proc)
Definition: proc.h:424
PGPROC * BackendPidGetProc(int pid)
Definition: procarray.c:3196
#define INVALID_PROC_NUMBER
Definition: procnumber.h:26
int ProcNumber
Definition: procnumber.h:24
int SendProcSignal(pid_t pid, ProcSignalReason reason, ProcNumber procNumber)
Definition: procsignal.c:281
@ PROCSIG_LOG_MEMORY_CONTEXT
Definition: procsignal.h:37
PGPROC * AuxiliaryPidGetProc(int pid)
Definition: proc.c:1040
Definition: proc.h:162

References AuxiliaryPidGetProc(), BackendPidGetProc(), ereport, errmsg(), GetNumberFromPGProc, INVALID_PROC_NUMBER, PG_GETARG_INT32, PG_RETURN_BOOL, PROCSIG_LOG_MEMORY_CONTEXT, SendProcSignal(), and WARNING.

◆ PutMemoryContextsStatsTupleStore()

static void PutMemoryContextsStatsTupleStore ( Tuplestorestate tupstore,
TupleDesc  tupdesc,
MemoryContext  context,
HTAB context_id_lookup 
)
static

Definition at line 70 of file mcxtfuncs.c.

73{
74#define PG_GET_BACKEND_MEMORY_CONTEXTS_COLS 10
75
79 List *path = NIL;
80 const char *name;
81 const char *ident;
82 const char *type;
83
85
86 /*
87 * Figure out the transient context_id of this context and each of its
88 * ancestors.
89 */
90 for (MemoryContext cur = context; cur != NULL; cur = cur->parent)
91 {
92 MemoryContextId *entry;
93 bool found;
94
95 entry = hash_search(context_id_lookup, &cur, HASH_FIND, &found);
96
97 if (!found)
98 elog(ERROR, "hash table corrupted");
99 path = lcons_int(entry->context_id, path);
100 }
101
102 /* Examine the context itself */
103 memset(&stat, 0, sizeof(stat));
104 (*context->methods->stats) (context, NULL, NULL, &stat, true);
105
106 memset(values, 0, sizeof(values));
107 memset(nulls, 0, sizeof(nulls));
108
109 name = context->name;
110 ident = context->ident;
111
112 /*
113 * To be consistent with logging output, we label dynahash contexts with
114 * just the hash table name as with MemoryContextStatsPrint().
115 */
116 if (ident && strcmp(name, "dynahash") == 0)
117 {
118 name = ident;
119 ident = NULL;
120 }
121
122 if (name)
124 else
125 nulls[0] = true;
126
127 if (ident)
128 {
129 int idlen = strlen(ident);
130 char clipped_ident[MEMORY_CONTEXT_IDENT_DISPLAY_SIZE];
131
132 /*
133 * Some identifiers such as SQL query string can be very long,
134 * truncate oversize identifiers.
135 */
138
139 memcpy(clipped_ident, ident, idlen);
140 clipped_ident[idlen] = '\0';
141 values[1] = CStringGetTextDatum(clipped_ident);
142 }
143 else
144 nulls[1] = true;
145
146 switch (context->type)
147 {
148 case T_AllocSetContext:
149 type = "AllocSet";
150 break;
151 case T_GenerationContext:
152 type = "Generation";
153 break;
154 case T_SlabContext:
155 type = "Slab";
156 break;
157 case T_BumpContext:
158 type = "Bump";
159 break;
160 default:
161 type = "???";
162 break;
163 }
164
166 values[3] = Int32GetDatum(list_length(path)); /* level */
167 values[4] = int_list_to_array(path);
168 values[5] = Int64GetDatum(stat.totalspace);
169 values[6] = Int64GetDatum(stat.nblocks);
170 values[7] = Int64GetDatum(stat.freespace);
171 values[8] = Int64GetDatum(stat.freechunks);
172 values[9] = Int64GetDatum(stat.totalspace - stat.freespace);
173
174 tuplestore_putvalues(tupstore, tupdesc, values, nulls);
175 list_free(path);
176}
static Datum values[MAXATTR]
Definition: bootstrap.c:151
#define CStringGetTextDatum(s)
Definition: builtins.h:97
#define ERROR
Definition: elog.h:39
#define elog(elevel,...)
Definition: elog.h:225
Datum Int64GetDatum(int64 X)
Definition: fmgr.c:1807
@ HASH_FIND
Definition: hsearch.h:113
#define ident
Definition: indent_codes.h:47
List * lcons_int(int datum, List *list)
Definition: list.c:513
void list_free(List *list)
Definition: list.c:1546
int pg_mbcliplen(const char *mbstr, int len, int limit)
Definition: mbutils.c:1083
static Datum int_list_to_array(const List *list)
Definition: mcxtfuncs.c:48
#define PG_GET_BACKEND_MEMORY_CONTEXTS_COLS
#define MEMORY_CONTEXT_IDENT_DISPLAY_SIZE
Definition: mcxtfuncs.c:30
#define MemoryContextIsValid(context)
Definition: memnodes.h:145
#define NIL
Definition: pg_list.h:68
const char * ident
Definition: memnodes.h:132
const MemoryContextMethods * methods
Definition: memnodes.h:126
const char * name
Definition: memnodes.h:131
void(* stats)(MemoryContext context, MemoryStatsPrintFunc printfunc, void *passthru, MemoryContextCounters *totals, bool print_to_stderr)
Definition: memnodes.h:102
void tuplestore_putvalues(Tuplestorestate *state, TupleDesc tdesc, const Datum *values, const bool *isnull)
Definition: tuplestore.c:784
const char * type
const char * name
#define stat
Definition: win32_port.h:274

References Assert, MemoryContextId::context_id, CStringGetTextDatum, cur, elog, ERROR, HASH_FIND, hash_search(), MemoryContextData::ident, ident, Int32GetDatum(), Int64GetDatum(), int_list_to_array(), lcons_int(), list_free(), list_length(), MEMORY_CONTEXT_IDENT_DISPLAY_SIZE, MemoryContextIsValid, MemoryContextData::methods, name, MemoryContextData::name, NIL, PG_GET_BACKEND_MEMORY_CONTEXTS_COLS, pg_mbcliplen(), stat, MemoryContextMethods::stats, tuplestore_putvalues(), type, and values.

Referenced by pg_get_backend_memory_contexts().