On Wed, Sep 14, 2016 at 12:13 AM, Kouhei Kaigai <kai...@ak.jp.nec.com> wrote: > It looks to me pg_buffercache tries to allocate more than 1GB using > palloc(), when shared_buffers is more than 256GB. > > # show shared_buffers ; > shared_buffers > ---------------- > 280GB > (1 row) > > # SELECT buffers, d.datname, coalesce(c.relname, '???') > FROM (SELECT count(*) buffers, reldatabase, relfilenode > FROM pg_buffercache group by reldatabase, relfilenode) b > LEFT JOIN pg_database d ON d.oid = b.reldatabase > LEFT JOIN pg_class c ON d.oid = (SELECT oid FROM pg_database > WHERE datname = current_database()) > AND b.relfilenode = pg_relation_filenode(c.oid) > ORDER BY buffers desc; > ERROR: invalid memory alloc request size 1174405120 > > It is a situation to use MemoryContextAllocHuge(), instead of palloc(). > Also, it may need a back patching?
I guess so. Although it's not very desirable for it to use that much memory, I suppose if you have a terabyte of shared_buffers you probably have 4GB of memory on top of that to show what they contain. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers