Re: pgdump slowness

On 9/12/19 10:35 AM, Dhandapani Shanmugam wrote:
> Hi Guys,
>
> We are having wired issue. pg_dump taking more time to backup 320 GB of 
> table,the table has bytea data type with TOAST table associated it. Please 
> let me know, if this is the expected behavior of pg_dump or do i need to 
> tune any of the parameters. I tried to run pg_dump with parallel -j option 
> , still no improvement and there is no lock on the table as well. any 
> inputs are welcome

It took 16 hours to dump a 3TB v8.4 database that's full of bytea fields, 
using the 9.6 pg_dump with 8 threads.  This was from one DC to another 
*across a 10GB WAN link*.

Note that I *disabled compression* because the bytea fields contained 
non-compressible images.  Thus, the dump size was 2.2x larger than the 
actual database.

With compression enabled, the dump took a *lot* longer (though I didn't 
record those numbers).

Ron
-- 
Angular momentum makes the world go 'round.