digoal
2021-07-27
PostgreSQL , pg_resetxlog
解决大版本升级时oldest xid设置过渡问题, 导致需要scan all relation's
relfrozenxid so it can advance pg_control's oldest xid to be inside the
autovacuum_freeze_max_age range
pg_resetxlog: add option to set oldest xid & use by pg_upgrade
author Bruce Momjian <bruce@momjian.us>
Tue, 27 Jul 2021 02:38:15 +0000 (22:38 -0400)
committer Bruce Momjian <bruce@momjian.us>
Tue, 27 Jul 2021 02:38:15 +0000 (22:38 -0400)
commit 74cf7d46a91d601e0f8d957a7edbaeeb7df83efc
tree d39d0b0cd9b4b817e7ab7be03082509aede1f95f tree
parent 24ba1a87e4056ec34c8a685633a1a14fb89e5700 commit | diff
pg_resetxlog: add option to set oldest xid & use by pg_upgrade
Add pg_resetxlog -u option to set the oldest xid in pg_control.
Previously -x set this value be -2 billion less than the -x value.
However, this causes the server to immediately scan all relation's
relfrozenxid so it can advance pg_control's oldest xid to be inside the
autovacuum_freeze_max_age range, which is inefficient and might disrupt
diagnostic recovery. pg_upgrade will use this option to better create
the new cluster to match the old cluster.
Reported-by: Jason Harvey, Floris Van Nee
Discussion: https://postgr.es/m/20190615183759.GB239428@rfd.leadboat.com, 87da83168c644fd9aae38f546cc70295@opammb0562.comp.optiver.com
Author: Bertrand Drouvot
Backpatch-through: 9.6
您的愿望将传达给PG kernel hacker、数据库厂商等, 帮助提高数据库产品质量和功能, 说不定下一个PG版本就有您提出的功能点. 针对非常好的提议，奖励限量版PG文化衫、纪念品、贴纸、PG热门书籍等，奖品丰富，快来许愿。开不开森.
