čt 31. 10. 2019 v 16:51 odesílatel Igor Calabria <igor.calab...@gmail.com> napsal:
> Hi everyone, > > I was taking a look at pg_stat_statements module and noticed that it does > not collect any percentile metrics. I believe that It would be really handy > to have those available and I'd love to contribute with this feature. > > The basic idea is to accumulate the the query execution times using an > approximation structure like q-digest or t-digest and add those results to > the pg_stat_statements table as fixed columns. Something like this > > p90_time: > p95_time: > p99_time: > p70_time: > ... > > Another solution is to persist de digest structure in a binary column and > use a function to extract the desired quantile ilke this SELECT > approx_quantile(digest_times, 0.99) FROM pg_stat_statements > > What do you guys think? > + the idea But I am not sure about performance and memory overhead Pavel > Cheers, > >
