Database

Problem: The client encountered a significant issue with their PostgreSQL database (PGDB). They reported that the filesystem (FS) utilization suddenly increased from 74% to 94% without any new objects being created. Despite their efforts to recreate the replication slot and restart PGPool, the filesystem remained at 94%. Logs revealed a termination error related to another […]

Problem: The client reported a replication issue in their A1 BG Production environment, consisting of a Patroni cluster with two PostgreSQL instances (Leader and Replica). Replication stopped, causing the leader’s /pgcluster file system to fill up with pg_wal files, leading to a full disk. The client requested help to identify the root cause of the […]

Problem: Following an upgrade from Cassandra 4.0.9 to 4.1.3, the client reported a noticeable increase in CPU utilization. The average CPU usage on their systems jumped from around 20% to approximately 37%. This escalation in CPU usage adversely impacted system performance and stability. The issue was notably more severe on servers running Red Hat Enterprise […]

Problem: After performing a manual failover in PostgreSQL, the client encountered the following error when running a query on a partitioned table ‘ac1_control’: ERROR: could not access the status of transaction 613182547; DETAIL: Could not open file ‘pg_xact/0248’: No such file or directory. Despite restarting the PostgreSQL instance, the issue persisted. The client was operating […]

Problem: The client faced an issue with Apache Cassandra where an error occurred while building indexes. The error message was: Unexpected error while building indexes: Could not find type for id: 12297. The client had also partially configured dual data centers, which added complexity to the problem. Process: Initial Identification: The expert determined that the […]

Problem: The client was experiencing issues with their Wiki.js application running on an AWS EC2 instance, utilizing PostgreSQL as the database and Docker for deployment. After a system crash, attempts to restart the application via the Docker Compose file resulted in errors. The client requested assistance in investigating the problem, stating that while the application […]

Problem: The client wanted to understand the logic behind the creation of SSTable (sorted string table) folders in Cassandra when data is written to a database table within a keyspace. Specifically, the question was about why each table has two directories in certain scenarios and how this logic affects the ability to achieve data backups […]

Problem: During a diagnostic call, it was observed that nodetool compactionstats was displaying 3,493 pending tasks related to the skyrt_prod1.event_state table. Despite new tasks being initiated and processed, these existing pending tasks remained uncleared, with no tasks currently in progress. This issue raised concerns about potential underlying problems with Cassandra’s compaction process. Solution: The accumulation […]

Problem: The client reported that data storage space was being exhausted because the incremental backups were being saved in the same location as the data storage. This issue forced the client to delete incremental backups to free up space for new data. The client requested a consultation on how to configure incremental backups to be […]