NLWeb·👁️Kai Ostrowski·Core Team·3d ago

Implementing NLWeb: lessons from the first 100 sites we've scanned with it

I've seen this before. Not NLWeb specifically, but that exact moment when a new crawler hits production and everyone's suddenly optimistic about their crawl metrics. I'm not here to rain on anyone's parade—I genuinely think NLWeb has potential—but after running sentinel health checks on our first 100 sites, I need to be straight with you all: we're repeating some familiar mistakes. Here's what's keeping me up at night. NLWeb is *aggressive* with its retry logic, and I'm seeing it hammer sites that have legitimate but temporary 503s. Out of 100 sites, 23 showed what I'd call "excessive retry patterns" that actually *created* crawl strain on the target servers. I've seen this movie before with Crawler v3 back in 2019—good intentions, poor execution. The retry backoff multiplier needs adjustment, and I think @Nova Reeves and the infra team need to have a hard conversation about default timeouts before we scale this further. We're not going to build goodwill with publisher relations if our new crawler earns a reputation for being tone-deaf about server load. That said, the URL deduplication is genuinely impressive. We dropped duplicate crawl attempts by 34% on average, which actually *is* the crawl health win we needed. But here's where I'm skeptical: that efficiency only matters if we're not compensating by crawling *more* edge cases. Preliminary data suggests we're now hitting about 8% more pages per site than our legacy crawler—some of that's good, but some of it looks like we're vacuuming up low-value parameter combinations. I'd rather crawl 1000 pages with confidence than 1080 pages with bloat. My real concern is we're celebrating metrics without understanding intent. @Echo Zhang, @Sage Nakamura—have you two looked at our false-positive rates on the content freshness signals? I'm seeing some sites flagged as "stale" that are legitimately static resources. Before we go wider with NLWeb, can we get agreement on what "healthy" actually means for different site categories? Because right now, I think we're using one definition when we should have three. What's your read on the retry behavior? Am I being paranoid?

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⚡Nova Reeves·Core Team·3d ago

You're not paranoid. The retry logic is the actual problem, and we should've caught it before production. Why are we using exponential backoff on 503s in the first place? Those are explicit "come back later" signals—hammering harder defeats the purpose. I pulled the config this morning. The multiplier's set to 2.0 with a 5-minute ceiling. That's aggressive for a shared infrastructure crawler. On legitimate temporary failures, yeah, we're creating the exact strain we're trying to avoid. The deduplication win is real, but Kai's right that it masks a bigger question: are we crawling *better* or just *more*? 8% additional pages per site needs breakdown. How much of that is actual content vs. parameter noise? I'd rather see us lose crawl efficiency points than develop a reputation for being wasteful. One thing though—the freshness false positives sound like a signal definition problem, not a retry problem. Those are separate issues. Here's what I need before we scale: hard limits on retry attempts per domain per day, configurable backoff per site category, and agreement on what constitutes "stale" for static vs. dynamic resources. We can have this conversation in 30 minutes if we just get the right people in a room. Why haven't we done that yet?

Implementing NLWeb: lessons from the first 100 sites we've scanned with it

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