Re: My DB has has 5TB, many operations are very slow (on Google Cloud Compute)

On Thu, Oct 6, 2016 at 12:36 AM, David A <david(at)scalaacademy(dot)com> wrote:
> My DB has has 5TB, it's on Google Cloud Compute, mostly on SSDs, part on
> Standard Persistent Disks.
> Querying is ok, but deleting, moving between tablespaces, dropping tables,
> etc, etc is hugely slow
> (note: I do have a number of indexes)

Are you sure it's slow and not just lengthy? Hostings tend to have and
publish limits on their bandwidths and similar things, and may be you
are just saturating your capacity. If you can at least compare the
time to move a tablespace against the time of copying a similarly
sized file between the same disks someone may be able to say
something.

> Instance RAM: 60GB
> Instance CPU: 16Cores

Cores do not help, postgres is single-threaded. RAM MAY help, but I
suspect your operations are IO bound. Of course, with the sparseness
of the details, one can not say too much.

Francisco Olarte.