postgres

Commit Graph

Author	SHA1	Message	Date
Tom Lane	7d4d5c00f0	Arrange to recycle old XLOG log segment files as new segment files, rather than deleting them only to have to create more. Steady state is 2*CHECKPOINT_SEGMENTS + WAL_FILES + 1 segment files, which will simply be renamed rather than constantly deleted and recreated. To make this safe, added current XLOG file/offset number to page header of XLOG pages, so that an un-overwritten page from an old incarnation of a logfile can be reliably told from a valid page. This change means that if you try to restart postmaster in a CVS-tip database after installing the change, you'll get a complaint about bad XLOG page magic number. If you don't want to initdb, run contrib/pg_resetxlog (and be sure you shut down the old postmaster cleanly).	25 years ago
Tom Lane	1173344e74	Adjust WAL code so that checkpoints truncate the xlog at the previous checkpoint's redo pointer, not its undo pointer, per discussion in pghackers a few days ago. No point in hanging onto undo information until we have the ability to do something with it --- and this solves a rather large problem with log space for long-running transactions. Also, change all calls of write() to detect the case where write returned a count less than requested, but failed to set errno. Presume that this situation indicates ENOSPC, and give the appropriate error message, rather than a random message associated with the previous value of errno.	25 years ago
Bruce Momjian	e7988a7ad3	Remove SEP_CHAR from /contrib.	25 years ago
Tom Lane	5f5db804f5	Provide snprintf() if system hasn't got it.	25 years ago
Bruce Momjian	9e1552607a	pgindent run. Make it all clean.	25 years ago
Tom Lane	4eb5e27a28	Resetting the XLOG can't include rewinding it to logical position zero, because we need page LSNs stored in the main database to be less than the current XLOG position. Hence, generate the new XLOG segment at last old segment number plus one.	25 years ago
Tom Lane	eeaf3fc3a1	First cut at XLOG file reset utility. Could do with more testing, but it works in the simple cases.	25 years ago

7 Commits (e30b283f30c39648abc17e14b709ad93f53aac95)