Re: fstat vs. lseek

Robert Haas <robertmhaas@gmail.com> writes:
> In response to my blog post on lseek contention, someone posted a
> comment wherein they proposed using fstat() rather than lseek() to get
> file sizes.
> Patch and test results are attached.  Test runs are 5-minute runs with
> scale factor 100 and shared_buffers=8GB.

> Thoughts?

I'm a bit concerned by the fact that you've only tested this on one
operating system, and thus the performance characteristics could be
quite different elsewhere.  The comment in mdextend also points out
a way in which this might not be a win --- did you test anything besides
read-only scenarios?
        regards, tom lane