Search Postgresql Archives

Re: Predicting query runtime

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, Sep 13, 2016 at 2:54 PM, Istvan Soos <istvan.soos@xxxxxxxxx> wrote:
> On Tue, Sep 13, 2016 at 2:06 AM, Vinicius Segalin <vinisegalin@xxxxxxxxx> wrote:
>> 2016-09-12 18:22 GMT-03:00 Istvan Soos <istvan.soos@xxxxxxxxx>:
>>> At Heap we have non-trivial complexity in our analytical queries, and
>>> some of them can take a long time to complete. We did analyze features
>>> like the query planner's output, our query properties (type,
>>> parameters, complexity) and tried to automatically identify factors
>>> that contribute the most into the total query time. It turns out that
>>> you don't need to use machine learning for the basics, but at this
>>> point we were not aiming for predictions yet.
>>
>> And how did you do that? Manually analyzing some queries?
>
> In this case, it was automatic analysis and feature discovery. We were
> generating features out of our query parameters, out of the SQL
> string, and also out of the explain analyze output. For each of these
> features, we have examined the P(query is slow | feature is present),
> and measured its statistical properties (precision, recall,
> correlations...).
>
> With these we have built a decision tree-based partitioning, where our
> feature-predicates divided the queries into subsets. Such a tree could
> be used for predictions, or if we would like to be fancy, we could use
> the feature vectors to train a neural network.

FYI, please check https://pgconf.ru/2016/89977

>
> Hope this helps for now,
>   Istvan
>
>
> --
> Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-general


-- 
Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general



[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Postgresql Jobs]     [Postgresql Admin]     [Postgresql Performance]     [Linux Clusters]     [PHP Home]     [PHP on Windows]     [Kernel Newbies]     [PHP Classes]     [PHP Books]     [PHP Databases]     [Postgresql & PHP]     [Yosemite]
  Powered by Linux