Re: Patch: add timing of buffer I/O requests

On 10 April 2012 19:10, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Hmm.  Maybe we should think about numeric ms, which would have all the
>> same advantages but without the round-off error.
>
> Color me unimpressed ... numeric calculations are vastly more expensive
> than float, and where are you going to get timing data that has more
> than sixteen decimal digits of accuracy?

+1

Besides, how do you propose to solve the problem of storing numerics
in a fixed allocation of shared memory? The only comparable thing in
pg_stat_statements is the query string, which is capped at
track_activity_query_size bytes for this very reason.

--
Peter Geoghegan       http://www.2ndQuadrant.com/
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