Обсуждение: pgsql: More cleanup after failed reduced-lock-levels-for-DDL feature.
More cleanup after failed reduced-lock-levels-for-DDL feature. Turns out that use of ShareUpdateExclusiveLock or ShareRowExclusiveLock to protect DDL changes had gotten copied into several places that were not touched by either of Simon's original patches for the feature, and thus neither he nor I thought to revert them. (Indeed, it appears that two of these uses were committed *after* the reversion, which just goes to show that git merging is no panacea.) Change these places to use AccessExclusiveLock again. If we ever manage to resurrect that feature, we're going to have to think a bit harder about how to keep lock level usage in sync for DDL operations that aren't within the AlterTable infrastructure. Two of these bugs are only in HEAD, but one is in the 9.1 branch too. Alvaro found one of them, I found the other two. Branch ------ master Details ------- http://git.postgresql.org/pg/commitdiff/5ac5980744149f062ec599015ffe7a7689dd117b Modified Files -------------- src/backend/catalog/toasting.c | 10 ++++++---- src/backend/commands/trigger.c | 2 +- src/backend/rewrite/rewriteRemove.c | 4 ++-- 3 files changed, 9 insertions(+), 7 deletions(-)
On Fri, Oct 21, 2011 at 6:50 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote: > More cleanup after failed reduced-lock-levels-for-DDL feature. > > Turns out that use of ShareUpdateExclusiveLock or ShareRowExclusiveLock > to protect DDL changes had gotten copied into several places that were > not touched by either of Simon's original patches for the feature, and > thus neither he nor I thought to revert them. (Indeed, it appears that > two of these uses were committed *after* the reversion, which just goes > to show that git merging is no panacea.) Change these places to use > AccessExclusiveLock again. If we ever manage to resurrect that feature, > we're going to have to think a bit harder about how to keep lock level > usage in sync for DDL operations that aren't within the AlterTable > infrastructure. > > Two of these bugs are only in HEAD, but one is in the 9.1 branch too. > Alvaro found one of them, I found the other two. Very cool, thanks. -- Simon Riggs http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services