Re: MI - WAL issue

Hi,

From the logs, it looks like PostgreSQL is facing an issue while trying to
flush WAL during a checkpoint. I would suggest checking a few things:

- Check the PostgreSQL logs around the same time to see if there were
any other WAL, checkpoint, or I/O-related errors.
- Check the server/OS logs for any disk or filesystem issues around 10:58:56
MST.
- Check if there was any unexpected server or PostgreSQL restart,
storage issue, snapshot/rollback, or failover.
- Verify the disk and filesystem health and make sure there is enough
free space.
- Identify which table or index is related to base/16384/1255337, as
PostgreSQL was writing to this relation when the error occurred.
- Check if WAL archiving and replication are working fine, if configured.
- Also, make sure the latest backup is healthy and available for
recovery before taking any corrective action.

The export issue may just be a symptom of an underlying database or storage
problem, so I think these checks would be a good starting point.

Thanks & Regards
Gaurav Shukla
Ph: +91-7022636963

On Mon, Jul 27, 2026, 11:27 mahamood hussain <hussain(dot)ieg(at)gmail(dot)com> wrote:

> Hi team,
>
> I need some urgent assistance.
>
> We're running *PostgreSQL 17.6*, and the application team has reported an *export
> issue*. While investigating, I found the following messages in the
> PostgreSQL logs:
>
> 2026-07-26 10:58:52.902 MST [1183899] DETAIL: Parameters: $1 = '1785088732902', $2 = 'ctsserver-11783137027378'
> 2026-07-26 10:58:56.136 MST [1529364] LOG: checkpoint starting: time
> 2026-07-26 10:58:56.447 MST [1529364] LOG: request to flush past end of generated WAL; request 5D116/1, current position C8F/734E66C0
> 2026-07-26 10:58:56.447 MST [1529364] CONTEXT: writing block 4400857 of relation base/16384/1255337
> 2026-07-26 10:58:56.448 MST [1529364] ERROR: xlog flush request 5D116/1 is not satisfied --- flushed only to C8F/734E66C0
> 2026-07-26 10:58:56.448 MST [1529364] CONTEXT: writing block 4400857 of relation base/16384/1255337
>
> Has anyone come across this issue before or know what could cause it? Any
> guidance on the root cause or recommended troubleshooting steps would be
> greatly appreciated.
>
> This is a *Major Incident (MI)* and requires immediate assistance.
>
> Thanks in advance.
>