From: Alvaro Herrera Date: Fri, 28 Nov 2014 21:06:18 +0000 (-0300) Subject: Update transaction README for persistent multixacts X-Git-Tag: REL9_3_6~92 X-Git-Url: http://git.postgresql.org/gitweb/?a=commitdiff_plain;h=0dafa9584e64243cb4d305be903623d6e709c584;p=postgresql.git Update transaction README for persistent multixacts Multixacts are now maintained during recovery, but the README didn't get the memo. Backpatch to 9.3, where the divergence was introduced. --- diff --git a/src/backend/access/transam/README b/src/backend/access/transam/README index 3a32471e951..82ffb98680f 100644 --- a/src/backend/access/transam/README +++ b/src/backend/access/transam/README @@ -812,10 +812,7 @@ parent transaction to complete. Not all transactional behaviour is emulated, for example we do not insert a transaction entry into the lock table, nor do we maintain the transaction -stack in memory. Clog entries are made normally. Multixact is not maintained -because its purpose is to record tuple level locks that an application has -requested to prevent other tuple locks. Since tuple locks cannot be obtained at -all, there is never any conflict and so there is no reason to update multixact. +stack in memory. Clog and multixact entries are made normally. Subtrans is maintained during recovery but the details of the transaction tree are ignored and all subtransactions reference the top-level TransactionId directly. Since commit is atomic this provides correct lock wait behaviour