Re: ZFS filesystem - supported ?

On 10/23/21 07:29, Laura Smith wrote:
> Hi,
>
> Given an upcoming server upgrade, I'm contemplating moving away from XFS to ZFS (specifically the ZoL flavour via
Debian11). BTRFS seems to be falling away (e.g. with Redhat deprecating it etc.), hence my preference for ZFS.
 
>
> However, somewhere in the back of my mind I seem to have a recollection of reading about what could be described as a
"strongencouragement" to stick with more traditional options such as ext4 or xfs.
 
>
> A brief search of the docs for "xfs" didn't come up with anything, hence the question here.
>
> Thanks !
>
> Laura
>
>
Hi Laura,

May I ask why would you like to change file systems? Probably because of 
the snapshot capability? However, ZFS performance leaves much to be 
desired. Please see the following article:

https://www.phoronix.com/scan.php?page=article&item=ubuntu1910-ext4-zfs&num=1

This is relatively new, from 2019. On the page 3 there are tests with 
SQLite, Cassandra and RocksDB. Ext4 is much faster in all of them. 
Finally, there is another article about relational databases and ZFS:

https://blog.docbert.org/oracle-on-zfs/

In other words, I would test very thoroughly because your performance is 
likely to suffer. As for the supported part, that's not a problem. 
Postgres supports all modern file systems. It uses Posix system calls to 
manipulate, read and write files. Furthermore, if you need snapshots, 
disk arrays like NetApp, Hitachi or EMC can always provide that.

Regards



-- 
Mladen Gogala
Database Consultant
Tel: (347) 321-1217
https://dbwhisperer.wordpress.com