Web Crawler – Provisioning

How to estimate and provision resources for a large-scale web crawler.

What are the key considerations for provisioning a web crawler?

• Estimate workload based on file size and total number of files

• Calculate IOPS (Input/Output Operations Per Second)

• Apply scaling factor (e.g., ×5) to handle overhead and spikes

• Auto-scale resources based on observed complexity and load

How do you estimate workload for provisioning a web crawler?

By calculating the total data size (e.g., 1 billion files × 2 KB each) and throughput required to process it.

Why calculate IOPS (Input/Output Operations Per Second)?

To measure storage performance needs and ensure databases/blob storage can handle read/write operations at scale.

Why apply a scaling factor (e.g., ×5)?

To account for overhead, retries, and peak load — ensuring the crawler doesn’t fail under pressure.

Why use auto-scaling for provisioning?

So the crawler adjusts resources dynamically based on workload complexity and real-time demand.