High-volume write workload causes I/O saturation when autovacuum runs

Database with high write activity (pre-scheduled tasks workload) triggers autovacuum processes that cause I/O utilization to spike to 100%, with load averages hitting unusually high levels during business hours. Performance degradation is intermittent but recurring.

Isolate high-write databases to separate VMs or instances to prevent I/O contention with other workloads. Monitor I/O utilization after migration - success shows I/O dropping from 100% spikes to sustained <40% with average <15%. Consider tuning autovacuum_vacuum_cost_delay and autovacuum_vacuum_cost_limit to reduce I/O impact during business hours.