diff options
Diffstat (limited to 'src/include')
| -rw-r--r-- | src/include/storage/proc.h | 40 | ||||
| -rw-r--r-- | src/include/storage/procarray.h | 7 |
2 files changed, 14 insertions, 33 deletions
diff --git a/src/include/storage/proc.h b/src/include/storage/proc.h index e76ca8a11e8..21a8fbe9d0a 100644 --- a/src/include/storage/proc.h +++ b/src/include/storage/proc.h @@ -77,36 +77,8 @@ struct XidCache #define INVALID_PGPROCNO PG_INT32_MAX /* - * Flags for PGPROC.delayChkpt - * - * These flags can be used to delay the start or completion of a checkpoint - * for short periods. A flag is in effect if the corresponding bit is set in - * the PGPROC of any backend. - * - * For our purposes here, a checkpoint has three phases: (1) determine the - * location to which the redo pointer will be moved, (2) write all the - * data durably to disk, and (3) WAL-log the checkpoint. - * - * Setting DELAY_CHKPT_START prevents the system from moving from phase 1 - * to phase 2. This is useful when we are performing a WAL-logged modification - * of data that will be flushed to disk in phase 2. By setting this flag - * before writing WAL and clearing it after we've both written WAL and - * performed the corresponding modification, we ensure that if the WAL record - * is inserted prior to the new redo point, the corresponding data changes will - * also be flushed to disk before the checkpoint can complete. (In the - * extremely common case where the data being modified is in shared buffers - * and we acquire an exclusive content lock on the relevant buffers before - * writing WAL, this mechanism is not needed, because phase 2 will block - * until we release the content lock and then flush the modified data to - * disk.) - * - * Setting DELAY_CHKPT_COMPLETE prevents the system from moving from phase 2 - * to phase 3. This is useful if we are performing a WAL-logged operation that - * might invalidate buffers, such as relation truncation. In this case, we need - * to ensure that any buffers which were invalidated and thus not flushed by - * the checkpoint are actaully destroyed on disk. Replay can cope with a file - * or block that doesn't exist, but not with a block that has the wrong - * contents. + * Flags used only for type of internal functions + * GetVirtualXIDsDelayingChkptGuts and HaveVirtualXIDsDelayingChkptGuts. */ #define DELAY_CHKPT_START (1<<0) #define DELAY_CHKPT_COMPLETE (1<<1) @@ -185,6 +157,12 @@ struct PGPROC */ XLogRecPtr waitLSN; /* waiting for this LSN or higher */ int syncRepState; /* wait state for sync rep */ + bool delayChkptEnd; /* true if this proc delays checkpoint end; + * this doesn't have anything to do with + * sync rep but we don't want to change + * the size of PGPROC in released branches + * and thus must fit this new field into + * existing padding space */ SHM_QUEUE syncRepLinks; /* list link if process is in syncrep queue */ /* @@ -267,7 +245,7 @@ typedef struct PGXACT uint8 vacuumFlags; /* vacuum-related flags, see above */ bool overflowed; - int delayChkpt; /* for DELAY_CHKPT_* flags */ + bool delayChkpt; /* true if this proc delays checkpoint start */ uint8 nxids; } PGXACT; diff --git a/src/include/storage/procarray.h b/src/include/storage/procarray.h index a69632a70cb..ea116cae21f 100644 --- a/src/include/storage/procarray.h +++ b/src/include/storage/procarray.h @@ -92,9 +92,12 @@ extern TransactionId GetOldestXmin(Relation rel, int flags); extern TransactionId GetOldestActiveTransactionId(void); extern TransactionId GetOldestSafeDecodingTransactionId(bool catalogOnly); -extern VirtualTransactionId *GetVirtualXIDsDelayingChkpt(int *nvxids, int type); +extern VirtualTransactionId *GetVirtualXIDsDelayingChkpt(int *nvxids); +extern VirtualTransactionId *GetVirtualXIDsDelayingChkptEnd(int *nvxids); extern bool HaveVirtualXIDsDelayingChkpt(VirtualTransactionId *vxids, - int nvxids, int type); + int nvxids); +extern bool HaveVirtualXIDsDelayingChkptEnd(VirtualTransactionId *vxids, + int nvxids); extern PGPROC *BackendPidGetProc(int pid); extern PGPROC *BackendPidGetProcWithLock(int pid); |