Bill Moran <wmoran@collaborativefusion.com> writes:
> Does the creation of a temp file trigger any logging?

No; but it wouldn't be hard to add some if you wanted. I'd do it at
deletion, not creation, so you could log the size the file reached.
See FileClose() in src/backend/storage/file/fd.c.

> That leads to my other question. Assuming I've got lots of
> connections (which I do), how can I determine if work_mem is too
> high?

When you start swapping, you have a problem --- so watch vmstat or
local equivalent.

regards, tom lane

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