Google Bot Attempts to Crawl Shortest URLs First

http://russell.ballestrini.net/google-bot-attempts-to-crawl-shortest-urls-first/

by foxhop • 15 years ago

47 27 15 years ago

russell.ballestrini.net

meow• 15 years ago

That's probably because short urls usually tend to be static pages while long ones tend to be dynamically generated content.

personalcompute2• 15 years ago

His entire site that he observed this behavior on is static.

jules• 15 years ago

But Google doesn't know that.

esryl• 15 years ago

The site adheres to a strict url structure. /state/city/id/schoolname - entering from the homepage, the only way to crawl the site 1 level at a time would be crawling the shortest urls first. this structure is also emphasised in the breadcrumbs on every page, the shortest urls are also the ones with the most internal links.

why would you crawl the site in any other way?

foxhop2• 15 years ago

If you look at a particular city page you will notice that the cities are in alphabetical order, however google bot still crawls by length of url...

underdown• 15 years ago

"why would you crawl the site any other way?"

I could see crawling pages most likely to have changed first as those pages would most likely lead to fresh content.

abrudtkuhl• 15 years ago

It starts at the top of your sitemap - which are likely shorter URLs

bauchidgw• 15 years ago

cant confirm this - sitemaps are used for discovery -> the urls listed in the sitemap get pushed into the 'discovered urls queue' then this queue is prioritized for crawling- and - if there are no other factors - the shorter urls get prioritized higher (as there is a bigger chance that a shorter url is a canonical version of a longer url - well, the chance is bigger then the other way round

arn• 15 years ago

I noticed this behavior also when I was following Googlebot's crawl of my old pages after I had done a redesign.

it's not because of sitemap or because of url structure or because of dynamic content.

Mine were blog articles in the same format. This is how it was crawled:

sitename.com/year/mo/day/stub

sitename.com/year/mo/day/stub-one

sitename.com/year/mo/day/stub-one-two

sitename.com/year/mo/day/stub-one-two-three

sitename.com/year/mo/day/stub-one-two-three-four

personalcompute2• 15 years ago

I did a more scientific analysis of the googlebot requests in the provided log (graph! http://i.imgur.com/uMoUT.png) and it definitely looks like it is taking shortest urls first. Anyone else with a large site want to check as well for further data?

foxhop2• 15 years ago

Thanks for the graph, I've added it to the blog page

JonnieCache2• 15 years ago

There is probably some highly non-obvious reason that sorting your queue of URLs by length is optimal, which was arrived at after a lot of modelling and testing.

We're unlikely to ever know the answer unless someone from google explains it to us.

JonnieCache2• 15 years ago

Thinking about it more, its probably just a breadth-first search. Duh.

frisco• 15 years ago

Breadth-first search means crawling all of the links on the page and adding all of the links on the child pages to the queue at once rather than drilling down on one link-path first before moving to the other links on the first page. There's probably some highly non-obvious reason for crawling by url length.

_grrr• 15 years ago

A poor mans PageRank algorithm, assuming nothing else, would assign a higher PageRank to shorter site links on a page. Presumably the crawler visits pages with a higher PR first.

TuxPirate2• 15 years ago

Pagerank determine crawls rate amongst other things. I find it is also likely that short URLs (especially in the case of a directory-type site) are seen first by the spider and that this order is respected by the crawler (FIFO).

You can also ask in #seo on irc.freenode.net I know there are knowledgable SEO people in there who might be able to provide you with a decent answer.

AshleysBrain2• 15 years ago

It's probably just a short URL is a heuristic for an important site. www.site.com/section is probably more important than www.site.com/section/subsection/detail/page/5/comments. A good move for the crawler - don't get distracted by "deep" pages - try and stick to high level ones first.

Edit: this would also encourage webmasters to use short URLs, which benefits users by being easier to remember, too.

cma• 15 years ago

I don't agree with the last point; seems like it would encourage things like foo.com/1hu83FG2 or lead to excessive abbreviation.

DrJokepu• 15 years ago

If I remember correctly, your page ranks better in Google if the search terms are in the URL (even more so if they are in the hostname).

AshleysBrain2• 15 years ago

Well, it's just a heuristic. Also, would you consider that level of abbreviation for your own site instead of descriptive names? You do want users to be able to remember URLs if at all possible...

orijing2• 15 years ago

How well-known is this to webmasters? If it's not well-known I cannot see how the second part could be. But the first could very much be true, and is what I would've surmised.

TuxPirate2• 15 years ago

Pagerank determine crawls rate amongst other things (http://techpatio.com/2009/search-engines/google/matt-cutts-g...).

I find it is also likely that short URLs (especially in the case of a directory-type site) are seen first by the spider and that this order is respected by the crawler (FIFO).

You can also ask in #seo on irc.freenode.net I know there are knowledgable SEO people in there who might be able to provide you with a decent answer.

christianwilde• 15 years ago

I imagine that in these specific case is because longer URLs represent deeper pages on the site that are less "important" (in terms of internal incoming links and pagerank) than the shorter ones. It doesn't seem logical that google order the URLs by length and then crawl them in that order; probably the URL length can be a factor that the bot takes into account, but not the only one in the manner this article suggest :)

Anyway, good point, that deserves more testing to extract some conclussions

ignifero• 15 years ago

Maybe because that's how they are sorted in the hashtable/database they use to queue urls? Or maybe because they want to index the shortest pages first, so that they are processed before any duplicates with longer urls (i.e. get /articles/ before /articles/index.php)

georgemcbay• 15 years ago

I suspect you're on the right track with your first guess.

Most people posting here are looking for some sort of deep meaning in this when IMO it is more likely just due to a localized side-effect of doing something such as storing the urls in a trie-like structure and then iterating over it breadth-first.

orijing2• 15 years ago

The question that I have is whether this is a relative behavior (i.e. whether, for a given domain 'domain.com' Google prioritizes domain.com/short-url over domain.com/longer/url.html) or a global one (i.e. prioritizing short.com/url over very-long-domain.com/nested/pages/hierarchy.html, all else equal).

I can definitely see the local/relative effects being a natural consequence of prioritizing by pagerank, but the global part sounds more like a separate signal.

Does anyone have insights?

Google Bot Attempts to Crawl Shortest URLs First

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