On Fri, Oct 8, 2021 at 02:27:55PM -0700, Wells Oliver wrote: > Hi: I am restoring a ~100GB backup using 16 jobs from an EC2 instance to an RDS > instance (db.m6g.xlarge, which is 16GB RAM and 4 CPU) and it's dying midway > with the dreaded "SSL SYSCALL error: EOF detected" error. > > I did create a parameter group to hopefully speed the restoration process, it > includes: > > - wal_buffers 8192 (64MB) > - checkpoint_timeout 3600 (1h) > - min_wal_size 192 (192MB) > - max_wal_size 102400 (100GB) > - shared_buffers 524288 (4GB) > - synchronous_commit 0 (off) > - autovacuum 0 (off) > - maintenance_work_mem 2097152 (2GB) > - work_mem 32768 (32MB) > > I sourced these from a few different folks as well as some trial and error, but > now it's blowing up on me. > > If I revert the RDS instance back to default PG parameters, it restores, but it > takes 3x the time. Wow, that is weird. I see that error string happening when PG can't extend the receipt buffer on the client side: appendPQExpBufferStr(&conn->errorMessage, libpq_gettext("SSL SYSCALL error: EOF detected\n")); Can you check the server logs to see if there is any error there? If I had to take a guess, I would reduce maintenance_work_mem to 1GB and retest. -- Bruce Momjian <bruce@xxxxxxxxxx> https://momjian.us EDB https://enterprisedb.com If only the physical world exists, free will is an illusion.