On 19 August 2015 at 12:23, Kouhei Kaigai <kai...@ak.jp.nec.com> wrote:
> > -----Original Message----- > > From: David Rowley [mailto:david.row...@2ndquadrant.com] > > Sent: Wednesday, August 19, 2015 9:00 AM > > The size of your hash table is 101017630802 bytes, which is: > > > > david=# select pg_size_pretty(101017630802); > > > > pg_size_pretty > > ---------------- > > 94 GB > > (1 row) > > > > david=# set work_mem = '94GB'; > > ERROR: 98566144 is outside the valid range for parameter "work_mem" (64 > .. > > 2097151) > > > Hmm. Why I could set work_mem = '96GB' without error. > > It was described in the postgresql.conf. > > postgres=# SHOW work_mem; > work_mem > ---------- > 96GB > (1 row) > > > So I think the only way the following could cause an error, is if > bucket_size > > was 1, which it can't be. > > > > lbuckets = 1 << my_log2(hash_table_bytes / bucket_size); > > > > > > I think one day soon we'll need to allow larger work_mem sizes, but I > think there's > > lots more to do than this change. > > > I oversight this limitation, but why I can bypass GUC limitation check? I'm unable to get the server to start if I set work_mem that big. I also tried starting the start with 1GB work_mem then doing a pg_ctl reload. With each of these I get the same error message that I would have gotten if I had done; set work_mem = '96GB'; Which version are you running? Are you sure there's not changes in guc.c for work_mem's range? Regards David Rowley -- David Rowley http://www.2ndQuadrant.com/ <http://www.2ndquadrant.com/> PostgreSQL Development, 24x7 Support, Training & Services
