PostgreSQL Source Code  git master
ipci.c File Reference
#include "postgres.h"
#include "access/clog.h"
#include "access/commit_ts.h"
#include "access/heapam.h"
#include "access/multixact.h"
#include "access/nbtree.h"
#include "access/subtrans.h"
#include "access/syncscan.h"
#include "access/twophase.h"
#include "access/xlogprefetcher.h"
#include "access/xlogrecovery.h"
#include "commands/async.h"
#include "miscadmin.h"
#include "pgstat.h"
#include "postmaster/autovacuum.h"
#include "postmaster/bgworker_internals.h"
#include "postmaster/bgwriter.h"
#include "postmaster/postmaster.h"
#include "replication/logicallauncher.h"
#include "replication/origin.h"
#include "replication/slot.h"
#include "replication/walreceiver.h"
#include "replication/walsender.h"
#include "storage/bufmgr.h"
#include "storage/dsm.h"
#include "storage/ipc.h"
#include "storage/pg_shmem.h"
#include "storage/pmsignal.h"
#include "storage/predicate.h"
#include "storage/proc.h"
#include "storage/procarray.h"
#include "storage/procsignal.h"
#include "storage/sinvaladt.h"
#include "storage/spin.h"
#include "utils/guc.h"
#include "utils/snapmgr.h"
Include dependency graph for ipci.c:

Go to the source code of this file.

Functions

void RequestAddinShmemSpace (Size size)
 
Size CalculateShmemSize (int *num_semaphores)
 
void CreateSharedMemoryAndSemaphores (void)
 
void InitializeShmemGUCs (void)
 

Variables

int shared_memory_type = DEFAULT_SHARED_MEMORY_TYPE
 
shmem_startup_hook_type shmem_startup_hook = NULL
 
static Size total_addin_request = 0
 

Function Documentation

◆ CalculateShmemSize()

Size CalculateShmemSize ( int *  num_semaphores)

Definition at line 85 of file ipci.c.

86 {
87  Size size;
88  int numSemas;
89 
90  /* Compute number of semaphores we'll need */
91  numSemas = ProcGlobalSemas();
92  numSemas += SpinlockSemas();
93 
94  /* Return the number of semaphores if requested by the caller */
95  if (num_semaphores)
96  *num_semaphores = numSemas;
97 
98  /*
99  * Size of the Postgres shared-memory block is estimated via moderately-
100  * accurate estimates for the big hogs, plus 100K for the stuff that's too
101  * small to bother with estimating.
102  *
103  * We take some care to ensure that the total size request doesn't
104  * overflow size_t. If this gets through, we don't need to be so careful
105  * during the actual allocation phase.
106  */
107  size = 100000;
108  size = add_size(size, PGSemaphoreShmemSize(numSemas));
109  size = add_size(size, SpinlockSemaSize());
111  sizeof(ShmemIndexEnt)));
112  size = add_size(size, dsm_estimate_size());
113  size = add_size(size, BufferShmemSize());
114  size = add_size(size, LockShmemSize());
115  size = add_size(size, PredicateLockShmemSize());
116  size = add_size(size, ProcGlobalShmemSize());
117  size = add_size(size, XLogPrefetchShmemSize());
118  size = add_size(size, XLOGShmemSize());
119  size = add_size(size, XLogRecoveryShmemSize());
120  size = add_size(size, CLOGShmemSize());
121  size = add_size(size, CommitTsShmemSize());
122  size = add_size(size, SUBTRANSShmemSize());
123  size = add_size(size, TwoPhaseShmemSize());
124  size = add_size(size, BackgroundWorkerShmemSize());
125  size = add_size(size, MultiXactShmemSize());
126  size = add_size(size, LWLockShmemSize());
127  size = add_size(size, ProcArrayShmemSize());
128  size = add_size(size, BackendStatusShmemSize());
129  size = add_size(size, SInvalShmemSize());
130  size = add_size(size, PMSignalShmemSize());
131  size = add_size(size, ProcSignalShmemSize());
132  size = add_size(size, CheckpointerShmemSize());
133  size = add_size(size, AutoVacuumShmemSize());
134  size = add_size(size, ReplicationSlotsShmemSize());
135  size = add_size(size, ReplicationOriginShmemSize());
136  size = add_size(size, WalSndShmemSize());
137  size = add_size(size, WalRcvShmemSize());
138  size = add_size(size, PgArchShmemSize());
139  size = add_size(size, ApplyLauncherShmemSize());
140  size = add_size(size, SnapMgrShmemSize());
141  size = add_size(size, BTreeShmemSize());
142  size = add_size(size, SyncScanShmemSize());
143  size = add_size(size, AsyncShmemSize());
144  size = add_size(size, StatsShmemSize());
145 #ifdef EXEC_BACKEND
146  size = add_size(size, ShmemBackendArraySize());
147 #endif
148 
149  /* include additional requested shmem from preload libraries */
150  size = add_size(size, total_addin_request);
151 
152  /* might as well round it off to a multiple of a typical page size */
153  size = add_size(size, 8192 - (size % 8192));
154 
155  return size;
156 }
Size AsyncShmemSize(void)
Definition: async.c:516
Size AutoVacuumShmemSize(void)
Definition: autovacuum.c:3325
Size BackendStatusShmemSize(void)
Size BackgroundWorkerShmemSize(void)
Definition: bgworker.c:142
Size BufferShmemSize(void)
Definition: buf_init.c:157
size_t Size
Definition: c.h:541
Size CheckpointerShmemSize(void)
Definition: checkpointer.c:869
Size CLOGShmemSize(void)
Definition: clog.c:689
Size CommitTsShmemSize(void)
Definition: commit_ts.c:525
size_t dsm_estimate_size(void)
Definition: dsm.c:444
Size hash_estimate_size(long num_entries, Size entrysize)
Definition: dynahash.c:781
static Size total_addin_request
Definition: ipci.c:58
Size ApplyLauncherShmemSize(void)
Definition: launcher.c:688
Size LockShmemSize(void)
Definition: lock.c:3609
Size LWLockShmemSize(void)
Definition: lwlock.c:437
Size MultiXactShmemSize(void)
Definition: multixact.c:1825
Size BTreeShmemSize(void)
Definition: nbtutils.c:2070
Size ReplicationOriginShmemSize(void)
Definition: origin.c:502
Size PgArchShmemSize(void)
Definition: pgarch.c:149
Size StatsShmemSize(void)
Definition: pgstat_shmem.c:126
Size PMSignalShmemSize(void)
Definition: pmsignal.c:129
Size PGSemaphoreShmemSize(int maxSemas)
Definition: posix_sema.c:165
Size PredicateLockShmemSize(void)
Definition: predicate.c:1356
Size ProcArrayShmemSize(void)
Definition: procarray.c:379
Size ProcSignalShmemSize(void)
Definition: procsignal.c:111
Size add_size(Size s1, Size s2)
Definition: shmem.c:502
#define SHMEM_INDEX_SIZE
Definition: shmem.h:55
Size SInvalShmemSize(void)
Definition: sinvaladt.c:203
Size ReplicationSlotsShmemSize(void)
Definition: slot.c:117
Size SnapMgrShmemSize(void)
Definition: snapmgr.c:198
Size SpinlockSemaSize(void)
Definition: spin.c:55
int SpinlockSemas(void)
Definition: spin.c:64
Size ProcGlobalShmemSize(void)
Definition: proc.c:102
int ProcGlobalSemas(void)
Definition: proc.c:124
Size SUBTRANSShmemSize(void)
Definition: subtrans.c:185
Size SyncScanShmemSize(void)
Definition: syncscan.c:126
Size TwoPhaseShmemSize(void)
Definition: twophase.c:240
Size WalRcvShmemSize(void)
Size WalSndShmemSize(void)
Definition: walsender.c:3252
Size XLOGShmemSize(void)
Definition: xlog.c:4478
size_t XLogPrefetchShmemSize(void)
Size XLogRecoveryShmemSize(void)
Definition: xlogrecovery.c:446

References add_size(), ApplyLauncherShmemSize(), AsyncShmemSize(), AutoVacuumShmemSize(), BackendStatusShmemSize(), BackgroundWorkerShmemSize(), BTreeShmemSize(), BufferShmemSize(), CheckpointerShmemSize(), CLOGShmemSize(), CommitTsShmemSize(), dsm_estimate_size(), hash_estimate_size(), LockShmemSize(), LWLockShmemSize(), MultiXactShmemSize(), PgArchShmemSize(), PGSemaphoreShmemSize(), PMSignalShmemSize(), PredicateLockShmemSize(), ProcArrayShmemSize(), ProcGlobalSemas(), ProcGlobalShmemSize(), ProcSignalShmemSize(), ReplicationOriginShmemSize(), ReplicationSlotsShmemSize(), SHMEM_INDEX_SIZE, SInvalShmemSize(), SnapMgrShmemSize(), SpinlockSemas(), SpinlockSemaSize(), StatsShmemSize(), SUBTRANSShmemSize(), SyncScanShmemSize(), total_addin_request, TwoPhaseShmemSize(), WalRcvShmemSize(), WalSndShmemSize(), XLogPrefetchShmemSize(), XLogRecoveryShmemSize(), and XLOGShmemSize().

Referenced by CreateSharedMemoryAndSemaphores(), and InitializeShmemGUCs().

◆ CreateSharedMemoryAndSemaphores()

void CreateSharedMemoryAndSemaphores ( void  )

Definition at line 174 of file ipci.c.

175 {
176  PGShmemHeader *shim = NULL;
177 
178  if (!IsUnderPostmaster)
179  {
180  PGShmemHeader *seghdr;
181  Size size;
182  int numSemas;
183 
184  /* Compute the size of the shared-memory block */
185  size = CalculateShmemSize(&numSemas);
186  elog(DEBUG3, "invoking IpcMemoryCreate(size=%zu)", size);
187 
188  /*
189  * Create the shmem segment
190  */
191  seghdr = PGSharedMemoryCreate(size, &shim);
192 
193  InitShmemAccess(seghdr);
194 
195  /*
196  * Create semaphores
197  */
198  PGReserveSemaphores(numSemas);
199 
200  /*
201  * If spinlocks are disabled, initialize emulation layer (which
202  * depends on semaphores, so the order is important here).
203  */
204 #ifndef HAVE_SPINLOCKS
206 #endif
207  }
208  else
209  {
210  /*
211  * We are reattaching to an existing shared memory segment. This
212  * should only be reached in the EXEC_BACKEND case.
213  */
214 #ifndef EXEC_BACKEND
215  elog(PANIC, "should be attached to shared memory already");
216 #endif
217  }
218 
219  /*
220  * Set up shared memory allocation mechanism
221  */
222  if (!IsUnderPostmaster)
224 
225  /*
226  * Now initialize LWLocks, which do shared memory allocation and are
227  * needed for InitShmemIndex.
228  */
229  CreateLWLocks();
230 
231  /*
232  * Set up shmem.c index hashtable
233  */
234  InitShmemIndex();
235 
236  dsm_shmem_init();
237 
238  /*
239  * Set up xlog, clog, and buffers
240  */
241  XLOGShmemInit();
244  CLOGShmemInit();
248  InitBufferPool();
249 
250  /*
251  * Set up lock manager
252  */
253  InitLocks();
254 
255  /*
256  * Set up predicate lock manager
257  */
259 
260  /*
261  * Set up process table
262  */
263  if (!IsUnderPostmaster)
264  InitProcGlobal();
269 
270  /*
271  * Set up shared-inval messaging
272  */
274 
275  /*
276  * Set up interprocess signaling mechanisms
277  */
284  WalSndShmemInit();
285  WalRcvShmemInit();
286  PgArchShmemInit();
288 
289  /*
290  * Set up other modules that need some shared memory space
291  */
292  SnapMgrInit();
293  BTreeShmemInit();
295  AsyncShmemInit();
296  StatsShmemInit();
297 
298 #ifdef EXEC_BACKEND
299 
300  /*
301  * Alloc the win32 shared backend array
302  */
303  if (!IsUnderPostmaster)
304  ShmemBackendArrayAllocation();
305 #endif
306 
307  /* Initialize dynamic shared memory facilities. */
308  if (!IsUnderPostmaster)
310 
311  /*
312  * Now give loadable modules a chance to set up their shmem allocations
313  */
314  if (shmem_startup_hook)
316 }
void AsyncShmemInit(void)
Definition: async.c:533
void AutoVacuumShmemInit(void)
Definition: autovacuum.c:3344
void CreateSharedBackendStatus(void)
void BackgroundWorkerShmemInit(void)
Definition: bgworker.c:158
void InitBufferPool(void)
Definition: buf_init.c:68
void CheckpointerShmemInit(void)
Definition: checkpointer.c:888
void CLOGShmemInit(void)
Definition: clog.c:695
void CommitTsShmemInit(void)
Definition: commit_ts.c:536
void dsm_postmaster_startup(PGShmemHeader *shim)
Definition: dsm.c:150
void dsm_shmem_init(void)
Definition: dsm.c:453
#define DEBUG3
Definition: elog.h:28
#define PANIC
Definition: elog.h:42
bool IsUnderPostmaster
Definition: globals.c:113
shmem_startup_hook_type shmem_startup_hook
Definition: ipci.c:56
Size CalculateShmemSize(int *num_semaphores)
Definition: ipci.c:85
void ApplyLauncherShmemInit(void)
Definition: launcher.c:736
void InitLocks(void)
Definition: lock.c:405
void CreateLWLocks(void)
Definition: lwlock.c:467
void MultiXactShmemInit(void)
Definition: multixact.c:1842
void BTreeShmemInit(void)
Definition: nbtutils.c:2083
void ReplicationOriginShmemInit(void)
Definition: origin.c:522
void PgArchShmemInit(void)
Definition: pgarch.c:160
void StatsShmemInit(void)
Definition: pgstat_shmem.c:140
void PMSignalShmemInit(void)
Definition: pmsignal.c:144
void PGReserveSemaphores(int maxSemas)
Definition: posix_sema.c:196
void InitPredicateLocks(void)
Definition: predicate.c:1153
void CreateSharedProcArray(void)
Definition: procarray.c:421
void ProcSignalShmemInit(void)
Definition: procsignal.c:125
void InitShmemIndex(void)
Definition: shmem.c:292
void InitShmemAllocation(void)
Definition: shmem.c:116
void InitShmemAccess(void *seghdr)
Definition: shmem.c:101
void CreateSharedInvalidationState(void)
Definition: sinvaladt.c:227
void ReplicationSlotsShmemInit(void)
Definition: slot.c:135
void SnapMgrInit(void)
Definition: snapmgr.c:214
void SpinlockSemaInit(void)
Definition: spin.c:77
void InitProcGlobal(void)
Definition: proc.c:159
void SUBTRANSShmemInit(void)
Definition: subtrans.c:191
void SyncScanShmemInit(void)
Definition: syncscan.c:135
PGShmemHeader * PGSharedMemoryCreate(Size size, PGShmemHeader **shim)
Definition: sysv_shmem.c:691
void TwoPhaseShmemInit(void)
Definition: twophase.c:256
void WalRcvShmemInit(void)
void WalSndShmemInit(void)
Definition: walsender.c:3264
void XLOGShmemInit(void)
Definition: xlog.c:4528
void XLogPrefetchShmemInit(void)
void XLogRecoveryShmemInit(void)
Definition: xlogrecovery.c:457

References ApplyLauncherShmemInit(), AsyncShmemInit(), AutoVacuumShmemInit(), BackgroundWorkerShmemInit(), BTreeShmemInit(), CalculateShmemSize(), CheckpointerShmemInit(), CLOGShmemInit(), CommitTsShmemInit(), CreateLWLocks(), CreateSharedBackendStatus(), CreateSharedInvalidationState(), CreateSharedProcArray(), DEBUG3, dsm_postmaster_startup(), dsm_shmem_init(), elog(), InitBufferPool(), InitLocks(), InitPredicateLocks(), InitProcGlobal(), InitShmemAccess(), InitShmemAllocation(), InitShmemIndex(), IsUnderPostmaster, MultiXactShmemInit(), PANIC, PgArchShmemInit(), PGReserveSemaphores(), PGSharedMemoryCreate(), PMSignalShmemInit(), ProcSignalShmemInit(), ReplicationOriginShmemInit(), ReplicationSlotsShmemInit(), shmem_startup_hook, SnapMgrInit(), SpinlockSemaInit(), StatsShmemInit(), SUBTRANSShmemInit(), SyncScanShmemInit(), TwoPhaseShmemInit(), WalRcvShmemInit(), WalSndShmemInit(), XLogPrefetchShmemInit(), XLogRecoveryShmemInit(), and XLOGShmemInit().

Referenced by BootstrapModeMain(), PostgresSingleUserMain(), PostmasterMain(), and PostmasterStateMachine().

◆ InitializeShmemGUCs()

void InitializeShmemGUCs ( void  )

Definition at line 325 of file ipci.c.

326 {
327  char buf[64];
328  Size size_b;
329  Size size_mb;
330  Size hp_size;
331 
332  /*
333  * Calculate the shared memory size and round up to the nearest megabyte.
334  */
335  size_b = CalculateShmemSize(NULL);
336  size_mb = add_size(size_b, (1024 * 1024) - 1) / (1024 * 1024);
337  sprintf(buf, "%zu", size_mb);
338  SetConfigOption("shared_memory_size", buf,
340 
341  /*
342  * Calculate the number of huge pages required.
343  */
344  GetHugePageSize(&hp_size, NULL);
345  if (hp_size != 0)
346  {
347  Size hp_required;
348 
349  hp_required = add_size(size_b / hp_size, 1);
350  sprintf(buf, "%zu", hp_required);
351  SetConfigOption("shared_memory_size_in_huge_pages", buf,
353  }
354 }
void SetConfigOption(const char *name, const char *value, GucContext context, GucSource source)
Definition: guc.c:4157
@ PGC_S_DYNAMIC_DEFAULT
Definition: guc.h:110
@ PGC_INTERNAL
Definition: guc.h:69
static char * buf
Definition: pg_test_fsync.c:67
#define sprintf
Definition: port.h:240
void GetHugePageSize(Size *hugepagesize, int *mmap_flags)
Definition: sysv_shmem.c:478

References add_size(), buf, CalculateShmemSize(), GetHugePageSize(), PGC_INTERNAL, PGC_S_DYNAMIC_DEFAULT, SetConfigOption(), and sprintf.

Referenced by PostgresSingleUserMain(), and PostmasterMain().

◆ RequestAddinShmemSpace()

void RequestAddinShmemSpace ( Size  size)

Definition at line 70 of file ipci.c.

71 {
73  elog(FATAL, "cannot request additional shared memory outside shmem_request_hook");
75 }
#define FATAL
Definition: elog.h:41
bool process_shmem_requests_in_progress
Definition: miscinit.c:1769

References add_size(), elog(), FATAL, process_shmem_requests_in_progress, and total_addin_request.

Referenced by autoprewarm_shmem_request(), pgss_shmem_request(), and test_slru_shmem_request().

Variable Documentation

◆ shared_memory_type

int shared_memory_type = DEFAULT_SHARED_MEMORY_TYPE

Definition at line 54 of file ipci.c.

Referenced by PGSharedMemoryCreate().

◆ shmem_startup_hook

shmem_startup_hook_type shmem_startup_hook = NULL

Definition at line 56 of file ipci.c.

Referenced by _PG_init(), and CreateSharedMemoryAndSemaphores().

◆ total_addin_request

Size total_addin_request = 0
static

Definition at line 58 of file ipci.c.

Referenced by CalculateShmemSize(), and RequestAddinShmemSpace().