Re: Parallel copy

From: Heikki Linnakangas <hlinnaka(at)iki(dot)fi>
To: vignesh C <vignesh21(at)gmail(dot)com>, Bharath Rupireddy <bharath(dot)rupireddyforpostgres(at)gmail(dot)com>
Cc: PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org>
Subject: Re: Parallel copy
Date: 2020-10-29 08:50:44
Message-ID: e610297e-2a3b-e71d-1b65-85cd1185f342@iki.fi
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On 27/10/2020 15:36, vignesh C wrote:
> Attached v9 patches have the fixes for the above comments.

I did some testing:

/tmp/longdata.pl:
--------
#!/usr/bin/perl
#
# Generate three rows:
# foo
# longdatalongdatalongdata...
# bar
#
# The length of the middle row is given as command line arg.
#

my $bytes = $ARGV[0];

print "foo\n";
for(my $i = 0; $i < $bytes; $i+=8){
print "longdata";
}
print "\n";
print "bar\n";
--------

postgres=# copy longdata from program 'perl /tmp/longdata.pl 100000000'
with (parallel 2);

This gets stuck forever (or at least I didn't have the patience to wait
it finish). Both worker processes are consuming 100% of CPU.

- Heikki

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Daniel Westermann (DWE) 2020-10-29 08:56:39 Re: Parallel copy
Previous Message Heikki Linnakangas 2020-10-29 08:17:20 Re: Deduplicate aggregates and transition functions in planner