Adding upstream version 1.44.3.upstream/1.44.3

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

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+### Understand the alert
+
+The `postgres_table_bloat_size_perc` alert measures the bloat size percentage in a PostgreSQL database table. If you receive this alert, it means that the bloat size in a particular table in your PostgreSQL database has crossed the warning or critical threshold.
+
+### What is bloat size?
+
+In PostgreSQL, bloat size refers to the wasted storage space caused by dead rows and unused space that accumulates in database tables over time. It is a result of frequent database operations (inserts, updates, and deletes), impacting database performance and storage footprint.
+
+### Troubleshoot the alert
+
+- Investigate the bloat size and impacted table
+
+To get a detailed report on bloated tables in your PostgreSQL database, use the [`pgstattuple`](https://www.postgresql.org/docs/current/pgstattuple.html) extension. First, install the extension if it isn't already installed:
+
+   ```
+   CREATE EXTENSION pgstattuple;
+   ```
+
+Then, run the following query to find the bloated tables:
+
+   ```sql
+   SELECT 
+      schemaname, tablename, 
+      pg_size_pretty(bloat_size) AS bloat_size,
+      round(bloat_ratio::numeric, 2) AS bloat_ratio
+   FROM (
+      SELECT 
+         schemaname, tablename,
+         bloat_size, table_size, (bloat_size / table_size) * 100 as bloat_ratio 
+      FROM pgstattuple.schema_bloat
+   ) sub_query
+   WHERE bloat_ratio > 10
+   ORDER BY bloat_ratio DESC;
+   ```
+
+- Reclaim storage space
+
+Reducing the bloat size in PostgreSQL tables involves reclaiming wasted storage space. Here are two approaches:
+
+  1. **VACUUM**: The `VACUUM` command helps clean up dead rows and compact the space used by the table. Use the following command to clean up the impacted table:
+
+      ```
+      VACUUM VERBOSE ANALYZE <schema_name>.<table_name>;
+      ```
+
+  2. **REINDEX**: If the issue persists after using `VACUUM`, consider REINDEXing the table. This command rebuilds the table's indexes, which can improve query performance and reduce bloat. It can be more intrusive than `VACUUM`, be sure you understand its implications before running:
+
+      ```
+      REINDEX TABLE <schema_name>.<table_name>;
+      ```
+
+- Monitor the bloat size
+
+Continue monitoring the bloat size in your PostgreSQL tables by regularly checking the `postgres_table_bloat_size_perc` alert on Netdata.
+
+### Useful resources
+
+1. [How to monitor and fix Database bloats in PostgreSQL?](https://blog.netdata.cloud/postgresql-database-bloat/)