Which One of these Nodes Doesn’t Belong? A Vertica Quick Tip

Jim Knicely wrote this tip. We strongly recommend that you use a homogeneous hardware configuration for your Vertica cluster: Each node of the cluster should be similar in CPU, clock speed, number of cores, memory, and operating system version. We learned in the last Vertica Quick Tip that the V_CATALOG.HOST_RESOURCES system table provides a snapshot of the nodes in a Vertica cluster. We can use the information in that table to find “odd ball” node(s) in our cluster that are different from the majority of nodes! Example: dbadmin=> SELECT host_name, processor_count, processor_core_count, processor_description, ROUND(total_memory_bytes / 1024^3, 2) total_memory_gbytes FROM V_MONITOR.HOST_RESOURCES; host_name | processor_count | processor_core_count | processor_description | total_memory_gbytes ---------------+-----------------+----------------------+------------------------------------------+--------------------- 192.168.2.200 | 1 | 1 | Intel(R) Core(TM) i5-4300U CPU @ 1.90GHz | 2.78 192.168.2.201 | 1 | 1 | Intel(R) Core(TM) i5-4300U CPU @ 1.90GHz | 2.78 192.168.2.202 | 1 | 2 | Intel(R) Core(TM) i5-4300U CPU @ 1.90GHz | 2.78 (3 rows) dbadmin=> SELECT a.host_name, a.processor_count, a.processor_core_count, a.processor_description, ROUND(a.total_memory_bytes / 1024^3, 2) total_memory_gbytes dbadmin-> FROM V_MONITOR.HOST_RESOURCES a dbadmin-> JOIN (SELECT processor_count, processor_core_count, processor_description, total_memory_bytes dbadmin(> FROM V_MONITOR.HOST_RESOURCES dbadmin(> MINUS dbadmin(> SELECT processor_count, processor_core_count, processor_description, total_memory_bytes dbadmin(> FROM V_MONITOR.HOST_RESOURCES dbadmin(> GROUP BY 1, 2, 3, 4 dbadmin(> HAVING COUNT(*) > 1) b dbadmin-> USING (processor_count, processor_core_count, processor_description, total_memory_bytes); host_name | processor_count | processor_core_count | processor_description | total_memory_gbytes —————+—————–+———————-+——————————————+——————— 192.168.2.202 | 1 | 2 | Intel(R) Core(TM) i5-4300U CPU @ 1.90GHz | 2.78 (1 row) Have Fun!