On Tue, Dec 10, 2013 at 11:00 PM, Mason Sharp <msharp@xxxxxxxxxxxxxxxx> wrote: > In our StormDB fork (now TransLattice Storm) I made some changes to address > some issues that were uncovered with XC. I am not sure if it will address > this specific issue above, but in most cases we make it an error instead of > falling back to a local XID like XC does (imagine if a node cannot reach GTM > and autovacuum starts cleaning up data with local XIDs and snapshots) . Yep, falling back to a local xid when GTM is not reachable has been done since the beginning of the project. Considering that as a bug using the argument that it endangers data visibility, such a patch should be back-patched as well. Some insight on those remarks from the core team would be welcome though. > Also, we use GTM for getting XIDs for authentication and for autovacuum > launcher because in concurrency testing not doing so results in the same XID > being consumed by other sessions and causing hanging and other transaction > problems. The bottom line is falling back to local XIDs and snapshots should > almost always be avoided (initdb is ok). Check. > Our code is a bit different from vanilla XC, but I can try to put together a > similar patch soon. This would be welcome. > As a community I feel we should prioritize more on testing and bug fixing > like the reported issue and replicated table handling than on new features > like the merged coordinator and datanode project. Definitely, *normal* developers cannot afford spending so much time on projects as big as that. One of the big things that I see missing is a public instance of an XC buildfarm, by using for example the buildfarm code of Postgres that simply fetches the code from git, and kicks in-core tests. For XC this should be restricted though to regressions, and compilation. pg_upgrade or isolation tests are not really working... Regards, -- Michael -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
