On Sat, Nov 21, 2015 at 12:38 AM, Jim Nasby <jim.na...@bluetreble.com> wrote: > On 11/19/15 7:29 PM, Amit Langote wrote: >>> >>> Another option is to provide the means for the index scan routines to >>> >report their progress. Maybe every index AM won't use it, but it'd >>> >certainly be a lot better than staring at a long_running boolean. >> >> The boolean would be a workaround for sure. I'm also slightly tempted by >> the idea of instrumenting vacuum scans of individual index AM's bulkdelete >> methods. One precedent is how vacuum_delay_point() are sprinkled around in >> the code. Another problem to solve would be to figure out how to pass >> progress parameters around - via some struct or could they be globals just >> like VacuumCost* variables are... > > It just occurred to me that we could do the instrumentation in > lazy_tid_reaped(). It might seem bad to do in increment for every tuple in > an index, but we're already doing a bsearch over the dead tuple list. > Presumably that's going to be a lot more expensive than an increment > operation.
I think the cost of doing an increment there would be negligible. I'm not quite sure whether that's the right place to instrument - though it looks like it might be - but I think the cost of ++something in that function isn't gonna be a problem at all. -- 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
