Tom Lane 295e63983d Implement lazy XID allocation: transactions that do not modify any database ... rows will normally never obtain an XID at all. We already did things this way for subtransactions, but this patch extends the concept to top-level transactions. In applications where there are lots of short read-only transactions, this should improve performance noticeably; not so much from removal of the actual XID-assignments, as from reduction of overhead that's driven by the rate of XID consumption. We add a concept of a "virtual transaction ID" so that active transactions can be uniquely identified even if they don't have a regular XID. This is a much lighter-weight concept: uniqueness of VXIDs is only guaranteed over the short term, and no on-disk record is made about them. Florian Pflug, with some editorialization by Tom.		2007-09-05 18:10:48 +00:00
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assert.c	A few fixups in error handling: mark pg_re_throw() as noreturn for gcc,	2007-05-04 02:01:02 +00:00
elog.c	Implement lazy XID allocation: transactions that do not modify any database	2007-09-05 18:10:48 +00:00
Makefile	Remove remains of old depend target.	2007-01-20 17:16:17 +00:00