|
| 1 | +#include"postgres.h" |
| 2 | + |
| 3 | +#include"access/htup_details.h" |
| 4 | +#include"catalog/pg_type.h" |
| 5 | +#include"funcapi.h" |
| 6 | +#include"miscadmin.h" |
| 7 | +#include"postmaster/bgworker.h" |
| 8 | +#include"storage/ipc.h" |
| 9 | +#include"storage/procarray.h" |
| 10 | +#include"storage/procsignal.h" |
| 11 | +#include"storage/s_lock.h" |
| 12 | +#include"storage/shm_mq.h" |
| 13 | +#include"storage/shm_toc.h" |
| 14 | +#include"storage/spin.h" |
| 15 | +#include"utils/guc.h" |
| 16 | +#include"utils/memutils.h" |
| 17 | +#include"utils/resowner.h" |
| 18 | +#include"utils/wait.h" |
| 19 | +#include"portability/instr_time.h" |
| 20 | + |
| 21 | +#include"pg_stat_wait.h" |
| 22 | + |
| 23 | +CollectorShmqHeader*hdr=NULL; |
| 24 | + |
| 25 | +staticvoid*pgsw; |
| 26 | +shm_toc*toc; |
| 27 | +shm_mq*mq; |
| 28 | +staticvolatilesig_atomic_tshutdown_requested= false; |
| 29 | + |
| 30 | +inthistorySize; |
| 31 | +inthistoryPeriod; |
| 32 | +boolhistorySkipLatch; |
| 33 | + |
| 34 | +staticvoidhandle_sigterm(SIGNAL_ARGS); |
| 35 | +staticvoidcollector_main(Datummain_arg); |
| 36 | + |
| 37 | +/* |
| 38 | + * Estimate shared memory space needed. |
| 39 | + */ |
| 40 | +Size |
| 41 | +CollectorShmemSize(void) |
| 42 | +{ |
| 43 | +shm_toc_estimatore; |
| 44 | +Sizesize; |
| 45 | + |
| 46 | +shm_toc_initialize_estimator(&e); |
| 47 | +shm_toc_estimate_chunk(&e,sizeof(CollectorShmqHeader)); |
| 48 | +shm_toc_estimate_chunk(&e, (Size)COLLECTOR_QUEUE_SIZE); |
| 49 | +shm_toc_estimate_keys(&e,2); |
| 50 | +size=shm_toc_estimate(&e); |
| 51 | + |
| 52 | +returnsize; |
| 53 | +} |
| 54 | + |
| 55 | +CollectorShmqHeader* |
| 56 | +GetCollectorMem(boolinit) |
| 57 | +{ |
| 58 | +boolfound; |
| 59 | +Sizesegsize=CollectorShmemSize(); |
| 60 | + |
| 61 | +pgsw=ShmemInitStruct("pg_stat_wait",segsize,&found); |
| 62 | +if (!init&& !found) |
| 63 | +{ |
| 64 | +ereport(ERROR, (errcode(ERRCODE_INTERNAL_ERROR), |
| 65 | +errmsg("A collector memory wasn't initialized yet"))); |
| 66 | +} |
| 67 | + |
| 68 | +if (!found) |
| 69 | +{ |
| 70 | +void*mq_mem; |
| 71 | + |
| 72 | +toc=shm_toc_create(PG_STAT_WAIT_MAGIC,pgsw,segsize); |
| 73 | +hdr=shm_toc_allocate(toc,sizeof(CollectorShmqHeader)); |
| 74 | +shm_toc_insert(toc,0,hdr); |
| 75 | + |
| 76 | +mq_mem=shm_toc_allocate(toc,COLLECTOR_QUEUE_SIZE); |
| 77 | +shm_toc_insert(toc,1,mq_mem); |
| 78 | +} |
| 79 | +else |
| 80 | +{ |
| 81 | +toc=shm_toc_attach(PG_STAT_WAIT_MAGIC,pgsw); |
| 82 | +hdr=shm_toc_lookup(toc,0); |
| 83 | +} |
| 84 | +returnhdr; |
| 85 | +} |
| 86 | + |
| 87 | +void |
| 88 | +RegisterWaitsCollector(void) |
| 89 | +{ |
| 90 | +BackgroundWorkerworker; |
| 91 | + |
| 92 | +/* set up common data for all our workers */ |
| 93 | +worker.bgw_flags=BGWORKER_SHMEM_ACCESS | |
| 94 | +BGWORKER_BACKEND_DATABASE_CONNECTION; |
| 95 | +worker.bgw_start_time=BgWorkerStart_ConsistentState; |
| 96 | +worker.bgw_restart_time=BGW_NEVER_RESTART; |
| 97 | +worker.bgw_main=collector_main; |
| 98 | +worker.bgw_notify_pid=0; |
| 99 | +snprintf(worker.bgw_name,BGW_MAXLEN,"pg_stat_wait collector"); |
| 100 | +worker.bgw_main_arg= (Datum)0; |
| 101 | +RegisterBackgroundWorker(&worker); |
| 102 | +} |
| 103 | + |
| 104 | +void |
| 105 | +AllocHistory(History*observations,intcount) |
| 106 | +{ |
| 107 | +observations->items= (HistoryItem*)palloc0(sizeof(HistoryItem)*count); |
| 108 | +observations->index=0; |
| 109 | +observations->count=count; |
| 110 | +observations->wraparound= false; |
| 111 | +} |
| 112 | + |
| 113 | +/* Read current wait information from proc, if readCurrent is true, |
| 114 | + * then it reads from currently going wait, and can be inconsistent |
| 115 | + */ |
| 116 | +int |
| 117 | +GetCurrentWaitsState(PGPROC*proc,HistoryItem*item,intidx) |
| 118 | +{ |
| 119 | +instr_timecurrentTime; |
| 120 | +#ifdefNOT_USED |
| 121 | +ProcWait*wait; |
| 122 | + |
| 123 | +if (idx==-1) |
| 124 | +return0; |
| 125 | + |
| 126 | +INSTR_TIME_SET_CURRENT(currentTime); |
| 127 | +wait=&proc->waits.waitsBuf[idx]; |
| 128 | +item->backendPid=proc->pid; |
| 129 | +item->classId= (int)wait->classId; |
| 130 | +if (item->classId==0) |
| 131 | +return0; |
| 132 | + |
| 133 | +item->eventId= (int)wait->eventId; |
| 134 | + |
| 135 | +INSTR_TIME_SUBTRACT(currentTime,wait->startTime); |
| 136 | +item->waitTime=INSTR_TIME_GET_MICROSEC(currentTime); |
| 137 | +memcpy(item->params,wait->params,sizeof(item->params)); |
| 138 | +#endif |
| 139 | +return1; |
| 140 | +} |
| 141 | + |
| 142 | +staticvoid |
| 143 | +handle_sigterm(SIGNAL_ARGS) |
| 144 | +{ |
| 145 | +intsave_errno=errno; |
| 146 | +shutdown_requested= true; |
| 147 | +if (MyProc) |
| 148 | +SetLatch(&MyProc->procLatch); |
| 149 | +errno=save_errno; |
| 150 | +} |
| 151 | + |
| 152 | +/* Circulation in history */ |
| 153 | +staticHistoryItem* |
| 154 | +get_next_observation(History*observations) |
| 155 | +{ |
| 156 | +HistoryItem*result; |
| 157 | + |
| 158 | +result=&observations->items[observations->index]; |
| 159 | +observations->index++; |
| 160 | +if (observations->index >=observations->count) |
| 161 | +{ |
| 162 | +observations->index=0; |
| 163 | +observations->wraparound= true; |
| 164 | +} |
| 165 | +returnresult; |
| 166 | +} |
| 167 | + |
| 168 | +/* Gets current waits from backends */ |
| 169 | +staticvoid |
| 170 | +write_waits_history(History*observations,TimestampTzcurrent_ts) |
| 171 | +{ |
| 172 | +inti; |
| 173 | + |
| 174 | +#ifdefNOT_USED |
| 175 | +LWLockAcquire(ProcArrayLock,LW_SHARED); |
| 176 | +for (i=0;i<ProcGlobal->allProcCount;++i) |
| 177 | +{ |
| 178 | +HistoryItemitem,*observation; |
| 179 | +PGPROC*proc=&ProcGlobal->allProcs[i]; |
| 180 | +intstateOk=GetCurrentWaitsState(proc,&item,proc->waits.readIdx); |
| 181 | + |
| 182 | +/* mark waits as read */ |
| 183 | +proc->waits.readIdx=-1; |
| 184 | + |
| 185 | +if (stateOk) |
| 186 | +{ |
| 187 | +if (historySkipLatch&&item.classId==WAIT_LATCH) |
| 188 | +continue; |
| 189 | + |
| 190 | +item.ts=current_ts; |
| 191 | +observation=get_next_observation(observations); |
| 192 | +*observation=item; |
| 193 | +} |
| 194 | +} |
| 195 | +LWLockRelease(ProcArrayLock); |
| 196 | +#endif |
| 197 | +} |
| 198 | + |
| 199 | +staticvoid |
| 200 | +send_history(History*observations,shm_mq_handle*mqh) |
| 201 | +{ |
| 202 | +intcount,i; |
| 203 | + |
| 204 | +if (observations->wraparound) |
| 205 | +count=observations->count; |
| 206 | +else |
| 207 | +count=observations->index; |
| 208 | + |
| 209 | +shm_mq_send(mqh,sizeof(count),&count, false); |
| 210 | +for (i=0;i<count;i++) |
| 211 | +shm_mq_send(mqh,sizeof(HistoryItem),&observations->items[i], false); |
| 212 | +} |
| 213 | + |
| 214 | +staticvoid |
| 215 | +collector_main(Datummain_arg) |
| 216 | +{ |
| 217 | +shm_mq*mq; |
| 218 | +shm_mq_handle*mqh; |
| 219 | +Historyobservations; |
| 220 | +MemoryContextold_context,collector_context; |
| 221 | + |
| 222 | +/* |
| 223 | + * Establish signal handlers. |
| 224 | + * |
| 225 | + * We want CHECK_FOR_INTERRUPTS() to kill off this worker process just as |
| 226 | + * it would a normal user backend. To make that happen, we establish a |
| 227 | + * signal handler that is a stripped-down version of die(). We don't have |
| 228 | + * any equivalent of the backend's command-read loop, where interrupts can |
| 229 | + * be processed immediately, so make sure ImmediateInterruptOK is turned |
| 230 | + * off. |
| 231 | + */ |
| 232 | +pqsignal(SIGTERM,handle_sigterm); |
| 233 | +BackgroundWorkerUnblockSignals(); |
| 234 | + |
| 235 | +hdr->latch=&MyProc->procLatch; |
| 236 | + |
| 237 | +CurrentResourceOwner=ResourceOwnerCreate(NULL,"pg_stat_wait collector"); |
| 238 | +collector_context=AllocSetContextCreate(TopMemoryContext, |
| 239 | +"pg_stat_wait context", |
| 240 | +ALLOCSET_DEFAULT_MINSIZE, |
| 241 | +ALLOCSET_DEFAULT_INITSIZE, |
| 242 | +ALLOCSET_DEFAULT_MAXSIZE); |
| 243 | +old_context=MemoryContextSwitchTo(collector_context); |
| 244 | +AllocHistory(&observations,historySize); |
| 245 | +MemoryContextSwitchTo(old_context); |
| 246 | + |
| 247 | +while (1) |
| 248 | +{ |
| 249 | +intrc; |
| 250 | +TimestampTzcurrent_ts; |
| 251 | + |
| 252 | +ResetLatch(&MyProc->procLatch); |
| 253 | +current_ts=GetCurrentTimestamp(); |
| 254 | +write_waits_history(&observations,current_ts); |
| 255 | + |
| 256 | +if (shutdown_requested) |
| 257 | +break; |
| 258 | + |
| 259 | +rc=WaitLatch(&MyProc->procLatch, |
| 260 | +WL_LATCH_SET |WL_TIMEOUT |WL_POSTMASTER_DEATH, |
| 261 | +historyPeriod); |
| 262 | + |
| 263 | +if (rc&WL_POSTMASTER_DEATH) |
| 264 | +exit(1); |
| 265 | + |
| 266 | +if (hdr->request==HISTORY_REQUEST) |
| 267 | +{ |
| 268 | +hdr->request=NO_REQUEST; |
| 269 | + |
| 270 | +mq= (shm_mq*)shm_toc_lookup(toc,1); |
| 271 | +shm_mq_set_sender(mq,MyProc); |
| 272 | +mqh=shm_mq_attach(mq,NULL,NULL); |
| 273 | +shm_mq_wait_for_attach(mqh); |
| 274 | + |
| 275 | +if (shm_mq_get_receiver(mq)!=NULL) |
| 276 | +send_history(&observations,mqh); |
| 277 | + |
| 278 | +shm_mq_detach(mq); |
| 279 | +} |
| 280 | +} |
| 281 | + |
| 282 | +MemoryContextReset(collector_context); |
| 283 | + |
| 284 | +/* |
| 285 | + * We're done. Explicitly detach the shared memory segment so that we |
| 286 | + * don't get a resource leak warning at commit time. This will fire any |
| 287 | + * on_dsm_detach callbacks we've registered, as well. Once that's done, |
| 288 | + * we can go ahead and exit. |
| 289 | + */ |
| 290 | +proc_exit(0); |
| 291 | +} |
