Re: optimize the value of vacthresh and anlthresh

Hi hackers
I find that the arithmetic square root is not very smooth, and the
logarithmic function is smoother,Looking at the graph, the log function
algorithm might be more appropriate,I want to hear from the experts

sqrt

[image: image.png]
log2

[image: image.png]

log
[image: image.png]
orginal
[image: image.png]
postgres=# select ln(100000)*1000;
?column?
--------------------
11512.925464970229
(1 row)

postgres=# select log(2,100000)*1000;
?column?
-----------------------
16609.640474436812000
(1 row)

postgres=#

postgres=# select log(10,100000)*1000;
?column?
----------------------
5000.000000000000000
(1 row)

wenhui qiu <qiuwenhuifx(at)gmail(dot)com> 于2024年11月4日周一 16:30写道：

> Hi hackers
> A few days ago, I was looking at the sql server documentation and
> found that sql server has optimized the algorithm related to updating
> statistics in the 2016 ,version,I think we can also learn from the
> implementation method of sql server to optimize the problem of automatic
> vacuum triggered by large tables，The Document link(
> https://learn.microsoft.com/en-us/sql/relational-databases/statistics/statistics?view=sql-server-ver16),I
> refer to the sql server implementation method, submit a patch, please see
> the attachment, hope to get the help of expert hackers
>