Re: BUG #18909: Query creates millions of temporary files and stalls

On Sat, 2025-05-03 at 12:27 -0400, Tom Lane wrote:
> Sergey Koposov <Sergey.Koposov@ed.ac.uk> writes:
> > #8  0x00005615d84f6a59 in ExecHashTableInsert (hashtable=0x5615da85e5c0, slot=0x5615da823378,
hashvalue=2415356794)
> >     at nodeHash.c:1714
> >         shouldFree = true
> >         tuple = 0x5615da85f5e8
> >         bucketno = 32992122
> >         batchno = 3521863
>
> Yeah, this confirms the idea that the hashtable has exploded into an
> unreasonable number of buckets and batches.  I don't know why a
> parallel hash join would be more prone to do that than a non-parallel
> one, though.  I'm hoping some of the folks who worked on PHJ will
> look at this.
>

Thanks

> What have you got work_mem set to?  I hope it's fairly large, if
> you need to join such large tables.
>

Here're  my memory settings

shared_buffers = 32GB
work_mem = 1GB


    S


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