Subject: Re: DB Files

From: Adrian Klaver <[email-masked]>
Date: Fri, 15 Nov 2024 07:47:41 -0800

On 11/15/24 06:27, Andy Hartman wrote:
> I created a  new table (V16) and then used SimplySql to take data from 
> mssql to the new Postgres table. The table is 212gig in size. Myquestion 
> comes from the files created on the OS(Windows2022 server) I can see 
> lots of files with the last being:
> 
> 2474695.143
> 
> They are all 1,048,576kb
> 
> Is this normal behaviour and could I have done something to use fewer 
> files and larger ones?

Read:

https://www.postgresql.org/docs/current/storage-file-layout.html

[...]

"When a table or index exceeds 1 GB, it is divided into gigabyte-sized 
segments. The first segment's file name is the same as the filenode; 
subsequent segments are named filenode.1, filenode.2, etc. This 
arrangement avoids problems on platforms that have file size 
limitations. (Actually, 1 GB is just the default segment size. The 
segment size can be adjusted using the configuration option 
--with-segsize when building PostgreSQL.) In principle, free space map 
and visibility map forks could require multiple segments as well, though 
this is unlikely to happen in practice."

[...]

> 
> 
> This table is created in a separate tablespace on a dedicated drive on 
> the windows file system.
> 
>   I'm just getting involved in this PostgreSql instance
> 
> THanks.

-- 
Adrian Klaver
[email-masked]

---

From: Andy Hartman <[email-masked]>
Date: Fri, 15 Nov 2024 10:49:57 -0500

Thanks... I just found that myself... so normal behavior then...