On Wed, Jun 10, 2015 at 10:57 PM, Kouhei Kaigai <kaigai@ak.jp.nec.com> wrote:
> The attached patch replaces this palloc0() by MemoryContextAllocHuge() + memset().
> Indeed, this hash table is constructed towards the relation with nrows=119994544,
> so, it is not strange even if hash-slot itself is larger than 1GB.
You forgot to attach the patch, I think. It looks to me like the size
of a HashJoinTuple is going to be 16 bytes, so 1GB/16 = ~64 million.
That's a lot of buckets, but maybe not unreasonably many if you've got
enough memory.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
