Crawl Priority Queue Design

Not all URLs deserve equal timing. A priority queue keeps urgent updates fresh without blowing budgets.

Queue tiers

• High: IndexNow notifications, manual uploads, compliance fixes.
• Standard: Scheduled sitemap crawls.
• Low: Rechecks for soft 404s or stale content with low traffic.

Implementation tips

• Use Pub/Sub or SQS with priority metadata.
• Reserve capacity: e.g., 30 percent high, 60 percent standard, 10 percent low.
• Track per-tenant concurrency so one customer cannot consume the entire pipeline.
• De-duplicate URLs across queues; keep a bloom filter or dedupe cache.

Monitoring

• Log queue depth and wait times per priority.
• Alert when high priority waits exceed SLA.
• Provide ops dashboards to reassign capacity during incidents.

CrawlBot example

CrawlBot’s scheduler service enforces priority queues and publishes run summaries so ops know exactly what ran. Copy this design for a predictable crawling pipeline.***