Tom Lane <[EMAIL PROTECTED]> writes: > Simon is essentially arguing that if we are willing to assume no > incomplete write() we may as well assume it for WAL too. This seems > to me to be raising the risk significantly, but I admit that I can't > put my finger on why exactly.
Actually I think we can deal with torn pages in the WAL more easily than in database files anyways. In database files we need to get the entire page correctly one way or the other so we need full_page_writes in order to be deal properly. In the WAL we just need to be able to detect torn pages and stop reading WAL at that point. That's easier and doesn't really need a CRC. We could just adopt the Sybase strategy of storing a unique id number every 512 bytes throughout the WAL page. If those numbers don't match then we have a torn page; the system crashed at that point and we should stop reading WAL pages. -- Gregory Stark EnterpriseDB http://www.enterprisedb.com ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly
