Re: Re: patch review : Add ability to constrain backend temporary file space

On Wed, Jun 1, 2011 at 7:35 PM, Mark Kirkwood
<mark(dot)kirkwood(at)catalyst(dot)net(dot)nz> wrote:
> Done - 'work_disk' it is to match 'work_mem'.

I guess I'm bikeshedding here, but I'm not sure I really buy this
parallel. work_mem is primarily a query planner parameter; it says,
if you're going to need more memory than this, then you have to
execute the plan some other way. This new parameter is not a query
planner paramater AIUI - its job is to KILL things if they exceed the
limit. In that sense it's more like statement_timeout. I can imagine
us wanting more parameters like this too. Kill the query if it...

...takes too long (statement_timeout)
...uses too much temporary file space (the current patch)
...uses too much CPU time
...uses too much RAM
...generates too much disk I/O
...has too high an estimated cost
...others?

So I'm not sure work_disk is a great name. Actually, work_mem is
already not a great name even for what it is, but at any rate I think
this is something different.

--
Robert Haas
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