Re: [HACKERS] Potential hot-standby bug around xacts committed but in xl_running_xacts

2017-05-02 Thread Simon Riggs
On 2 May 2017 at 18:06, Andres Freund wrote: >> What I suggest is that with logical decoding in mind we do this >> 1. Inject a new record XLOG_SNAPSHOT_START at the start of >> LogStandbySnapshot(). We start logical decoding from there. >> 2. Record any transactions that end >> 3. Now the full XL

Re: [HACKERS] Potential hot-standby bug around xacts committed but in xl_running_xacts

2017-05-01 Thread Craig Ringer
On 2 May 2017 at 13:12, Simon Riggs wrote: > What I suggest is that with logical decoding in mind we do this > 1. Inject a new record XLOG_SNAPSHOT_START at the start of > LogStandbySnapshot(). We start logical decoding from there. > 2. Record any transactions that end > 3. Now the full XLOG_RUNN

Re: [HACKERS] Potential hot-standby bug around xacts committed but in xl_running_xacts

2017-05-01 Thread Simon Riggs
On 1 May 2017 at 22:38, Andres Freund wrote: > The thread below > http://archives.postgresql.org/message-id/f37e975c-908f-858e-707f-058d3b1eb214%402ndquadrant.com > describes an issue in logical decoding that arises because > xl_running_xacts' contents aren't necessarily coherent with the conten

[HACKERS] Potential hot-standby bug around xacts committed but in xl_running_xacts

2017-05-01 Thread Andres Freund
Hi, The thread below http://archives.postgresql.org/message-id/f37e975c-908f-858e-707f-058d3b1eb214%402ndquadrant.com describes an issue in logical decoding that arises because xl_running_xacts' contents aren't necessarily coherent with the contents of the WAL, because RecordTransactionCommit() /