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+### Understand the alert
+
+This alert monitors the TOAST hit ratio (i.e., cached I/O efficiency) of a specific table in a PostgreSQL database. If the hit ratio is low, it indicates that the database is performing more disk I/O operations than needed for the table, which may cause performance issues.
+
+### What is TOAST?
+
+TOAST (The Oversized-Attribute Storage Technique) is a mechanism in PostgreSQL to efficiently store large data items. It allows you to store large values (such as text or binary data) in a separate table, improving the overall performance of the database.
+
+### What does the hit ratio mean?
+
+The hit ratio is the percentage of cache hits (successful reads from the cache) compared to total cache requests (hits + misses). A high hit ratio indicates that the data frequently needed is stored in the cache, resulting in fewer disk I/O operations and better performance.
+
+### Troubleshoot the alert
+
+1. Verify if the alert is accurate by checking the TOAST hit ratio in the affected PostgreSQL system. You can use the following query to retrieve the hit ratio of a specific table:
+
+   ```sql
+   SELECT CASE
+       WHEN blks_hit + blks_read = 0 THEN 0
+       ELSE 100 * blks_hit / (blks_hit + blks_read)
+   END as cache_hit_ratio
+   FROM pg_statio_user_tables
+   WHERE schemaname = 'your_schema' AND relname = 'your_table';
+   ```
+
+   Replace `your_schema` and `your_table` with the appropriate values.
+
+2. Examine the table's indexes, and consider creating new indexes to improve query performance. Be cautious when creating indexes, as too many can negatively impact performance.
+
+3. Analyze the table's read and write patterns to determine if you need to adjust the cache settings, such as increasing the `shared_buffers` configuration value.
+
+4. Inspect the application's queries to see if any can be optimized to improve performance. For example, use EXPLAIN ANALYZE to determine if the queries are using indexes effectively.
+
+5. Monitor overall PostgreSQL performance with tools like pg_stat_statements or pg_stat_activity to identify potential bottlenecks and areas for improvement.
+
+### Useful resources
+
+1. [PostgreSQL TOAST Overview](https://www.postgresql.org/docs/current/storage-toast.html)
+2. [Tuning Your PostgreSQL Server](https://wiki.postgresql.org/wiki/Tuning_Your_PostgreSQL_Server)