> On Dec 5, 2017, at 11:23 PM, Sergei Kornilov <s...@zsrv.org> wrote:
> You has very slow (or busy) disks, not postgresql issue. Reading 6760 * 8KB
> in 70 seconds is very bad result.
> For better performance you need better disks, at least raid10 (not raid5).
> Much more memory in shared_buffers can help with read performance and so
> reduce disk utilization, but write operations still will be slow.
Thanks so much for confirming, this really helps a lot to know what to do. I
thought the disk could be some of my issue, but I wanted to make sure I did all
of the obvious tuning first. I have learned some very valuable things which
I'll be able to use on future challenges like this which I didn't learn
Based on this advice from everyone, I'm setting up a box with more RAM, lots of
SSDs, and RAID 10. I'll write back in a few more days after I've completed it.
I can also confirm that the previous advice about using a hash / digest based
unique index seemed to make the loading process slower for me, not faster,
which is an interesting result to consider for future users following this
thread (if any). I don't yet have specific data how much slower, because it's
actually still going!