On Mon, Dec 7, 2015 at 8:33 AM, Fujii Masao <masao.fu...@gmail.com> wrote: > On Sat, Dec 5, 2015 at 12:56 AM, Alvaro Herrera > <alvhe...@2ndquadrant.com> wrote: >> Fujii Masao wrote: >> >>> Sorry for not reviewing the patch before you push it... >>> >>> In HEAD, I ran very simple test case: >>> >>> 1. enable track_commit_timestamp >>> 2. start the server >>> 3. run some transactions >>> 4. execute pg_last_committed_xact() -- returns non-null values >>> 5. shutdown the server with immdiate mode >>> 6. restart the server -- crash recovery happens >>> 7. execute pg_last_committed_xact() >>> >>> The last call of pg_last_committed_xact() returns NULL values, which means >>> that the xid and timestamp information of the last committed transaction >>> disappeared by crash recovery. Isn't this a bug? >> >> Hm, not really, because the status of the "last" transaction is kept in >> shared memory as a cache and not expected to live across a restart. >> However, I tested the equivalent scenario: >> >> alvherre=# create table fg(); >> CREATE TABLE >> >> alvherre=# select ts.* from pg_class,pg_xact_commit_timestamp(xmin) ts where >> relname = 'fg'; >> ts >> ------------------------------- >> 2015-12-04 12:41:48.017976-03 >> (1 fila) >> >> then crash the server, and after recovery the data is gone: >> >> alvherre=# select ts.*, xmin, c.relname from pg_class >> c,pg_xact_commit_timestamp(xmin) ts where relname = 'fg'; >> ts | xmin | relname >> ----+------+--------- >> | 630 | fg >> (1 fila) >> >> Not sure what is going on; my reading of the code certainly says that >> the data should be there. I'm looking into it. >> >> I also noticed that I didn't actually push the whole of the patch >> yesterday -- I neglected to "git add" the latest changes, the ones that >> fix the promotion scenario :-( so the commit messages is misleading >> because it describes something that's not there. > > So firstly you will push those "latest" changes soon?
It seems like these changes haven't been pushed yet, and unfortunately that's probably a beta blocker. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
