Re: Urgent !!!! Tables inaccessible postgres v17.6

Hi Matos,

Thanks for the response.

The PostgreSQL data volume is deployed using LVM striping, not mdadm. It
uses four Azure NVMe disks, combined into a ~2 TB LVM logical volume. The
LVM stripe size is 128 KiB.

I also looked into PostgreSQL tablespaces. While PostgreSQL supports
tablespaces, they don't provide the same capability as DB2 storage groups
and storage paths.

In DB2, a tablespace can be associated with a storage group, and the
storage group can have multiple storage paths. This allows the tablespace's
I/O to be distributed across multiple disks:

DB2 Database
|
Tablespace
|
Storage Group
|
+-----------+-----------+
| | |
Path 1 Path 2 Path 3
| | |
Disk 1 Disk 2 Disk 3

This is different from PostgreSQL, where a tablespace points to a single
filesystem/location. PostgreSQL itself doesn't provide the same
storage-group concept where one tablespace can directly use multiple
independent storage paths.

Therefore, if we want to distribute the I/O for a PostgreSQL tablespace
across multiple disks, that distribution needs to happen at the OS/storage
layer, for example through LVM striping or RAID.

This was the main reason I considered LVM striping for the PostgreSQL data
volume — to achieve a similar I/O distribution model to what we had with
DB2 storage groups and storage paths.

Please let me know if there is a better PostgreSQL/Azure architecture for
achieving the same level of IOPS and throughput without relying on OS-level
striping.

On Thu, Aug 13, 2026 at 5:49 PM Licio Matos <licio(dot)matos(at)gmail(dot)com> wrote:

> Hi,
>
> Just to confirm, are you using 4 disks in raid 0 from azure ssd v2? How
> they are deployed ,LVM or mdadm? What’s is the page size of the stripe?
>
> About tablespace, you can use tablespaces in PostgreSQL the same way.
>
> https://www.postgresql.org/docs/current/manage-ag-tablespaces.html
>
>
> Licio Matos
>
> Em qui., 13 de ago. de 2026 às 06:58, Ireneusz Pluta <ipluta(at)wp(dot)pl>
> escreveu:
>
>> W dniu 13.08.2026 o 10:55 AM, mahamood hussain pisze:
>> > are there any known limitations or risks with using RAID 0 even with
>> > the underlying durability provided by Premium SSD v2?
>> using RAID 0 is always a risk, regardless how much premium your hardware
>> is. Use RAID10 if you value your data.
>>
>>
>>