Using disk space in a PostgreSQL for 1C cluster

In Managed Databases, part of the disk space is reserved for service needs:

for the file system — approximately 4% of the disk volume;
for the operating system, service components, and logs — approximately 8 GB.

The reserved portion of the disk space is not available to host databases. Take this into account when selecting a configuration lineup.

You can monitor disk occupancy using disk occupancy notifications and metrics. For more information about metrics, see the Monitoring PostgreSQL for 1C clusters and nodes guide.

When the cluster disk is 95% full or more, the cluster will enter the DISK_FULL status and will operate in read-only mode. This is necessary to prevent complete locking or corruption of the cluster due to a lack of free space. To have the cluster operate in read-write mode, clear the disk or scale the cluster and choose a configuration with a larger disk size than the previous one.

Disk occupancy notifications

Disk occupancy notifications are sent to the email address of the Account Owner and users who are subscribed to the notification category "Services and products". Notifications are sent when the disk is 80% and 95% full.

Clear the disk

For your information

We do not recommend using the DELETE FROM table WHERE ... query to clear the disk. This query may create large selections on large tables and place them on the disk. The remaining free space on the disk may be completely exhausted, which will lead to problems with PostgreSQL and the need to manually restore its operation.

Open the transaction transaction_read_only = no and delete unnecessary data using one of the following queries:

DROP TABLE — completely deletes the table: data, structure, indexes, constraints (constraints), and triggers.
```
BEGIN;
SET transaction_read_only = no;
DROP TABLE table_name;
COMMIT;
```
TRUNCATE TABLE — deletes all rows from a table. It works faster than DELETE.
```
BEGIN;
SET transaction_read_only = no;
TRUNCATE TABLE table_name;
COMMIT;
```
DELETE — deletes rows specified in the WHERE condition.