OpenTransformer/web-crawl-2026

Web Crawl 2026

A large-scale web crawl dataset for language model pretraining, collected by the OpenTransformer project.

Dataset Description

This dataset contains text extracted from web pages crawled directly from the internet using custom high-throughput crawlers. All data is freshly scraped.

Data Format

Each record is a JSON line (gzipped) with fields:

• text: extracted text content (200-200,000 chars)
• url: source URL
• domain: source domain
• timestamp: crawl timestamp (ISO 8601)
• source: crawler identifier (crawl_rust_v1, crawl_go_v1, crawl_v5)

Collection Methods

Three crawlers run in parallel on a Vast.ai GPU box (Titan Xp, $0.06/hr):

Crawler	Language	Throughput	1.2GB Chunk Time	Architecture
crawl_rust	Rust	150-300 docs/s	5-6 min	500 async workers, tokio
crawl_go	Go	11 docs/s	~2 hrs	150 goroutines
crawl_v5.py	Python	0.8 docs/s	~25 hrs	20 async workers

The Rust crawler is 27x faster than Go and 375x faster than Python.

Rust Crawler Architecture

Source code: crawler/rust/

Key design decisions:

• 500 concurrent async workers via tokio + semaphore-based backpressure
• Background queue refiller: seed fetching runs in a separate task, never blocks crawling
• Pre-generated seed file: 593K URLs from Common Crawl index (12 crawl versions x 20 TLD patterns)
• Link discovery: extracts up to 50 links per crawled page, shuffled for domain diversity
• Content dedup: MD5 hash of first 500 chars, stored in DashMap (lock-free concurrent hashmap)
• Domain throttling: max 1000 pages per domain to ensure diversity
• Streaming gzip: writes compressed JSONL chunks (~1.2GB raw -> ~350MB compressed)
• Auto-upload: each completed chunk is uploaded to HuggingFace Hub

Seed sources:

1. Common Crawl URL index (CC-MAIN-2024-10 through CC-MAIN-2025-08)
2. Wikipedia random articles API (20K articles)
3. Sitemaps from 34 major sites (Reuters, BBC, Nature, StackOverflow, etc.)
4. Hacker News top/new/best stories

Performance on Titan Xp box ($0.06/hr):

• Phase 1: 562K seeds loaded in 28 seconds
• Phase 2: 150-300 docs/s sustained throughput
• ~1.2GB chunk every 5-6 minutes
• ~12-15 GB/hour of raw crawled text
• Cost: ~$0.004 per GB of crawled text

Building and Running

Install Rust, then:

cd crawler/rust
cargo build --release
ulimit -n 65536
./target/release/crawl_rust > crawl.log 2>&1

Quality Filtering

• HTML text extraction via scraper crate (article/main/body selectors)
• Minimum 200 chars, maximum 200K chars
• Content-type filtering (only text/html)
• URL filtering: blocks social media, login pages, media files, admin pages
• Deduplication via MD5 content hash

Intended Use

Pretraining data for the AGILLM-3 language model (698M params, joint AR+SAT architecture).

License

Apache 2.0