yahoo crawlers hammering us

Bruce Williams williams.bruce at
Wed Sep 8 09:21:31 UTC 2010

> I *am* curious--what makes it any worse for a search engine like Google
> to fetch the file than any other random user on the Internet

Possibly because that other user is who the customer pays have their
content delivered to?

Bruce Williams
You can close your eyes to things you don't want to see, but you can't
close your heart to the things you don't want to feel.

On Wed, Sep 8, 2010 at 12:04 AM, Matthew Petach <mpetach at> wrote:
> On Tue, Sep 7, 2010 at 1:19 PM, Ken Chase <ken at> wrote:
>> So i guess im new at internets as my colleagues told me because I havent gone
>> around to 30-40 systems I control (minus customer self-managed gear) and
>> installed a restrictive robots.txt everywhere to make the web less useful to
>> everyone.
>> Does that really mean that a big outfit like yahoo should be expected to
>> download stuff at high speed off my customers servers? For varying values of
>> 'high speed', ~500K/s (4Mbps+) for a 3 gig file is kinda... a bit harsh.
>> Especially for an exe a user left exposed in a webdir, thats possibly (C)
>> software and shouldnt have been there (now removed by customer, some kinda OS boot
>> cd/toolset thingy).
> The large search engines like Google, Bing, and Yahoo do try to be good
> netizens, and not have multiple crawlers hitting a given machine at the same
> time, and they put delays between each request, to be nice to the CPU load
> and bandwidth of the machines; but I don't think any of the crawlers explicitly
> make efforts to slow down single-file-fetches.  Ordinarily, the transfer speed
> doesn't matter as much for a single URL fetch, as it lasts a very short period
> of time, and then the crawler waits before doing another fetch from the same
> machine/same site, reducing the load on the machine being crawled.  I doubt
> any of them rate-limit down individual fetches, though, so you're likely to see
> more of an impact when serving up large single files like that.
> I *am* curious--what makes it any worse for a search engine like Google
> to fetch the file than any other random user on the Internet?  In either case,
> the machine doing the fetch isn't going to rate-limit the fetch, so
> you're likely
> to see the same impact on the machine, and on the bandwidth.
>> Is this expected/my own fault or what?
> Well...if you put a 3GB file out on the web, unprotected, you've got to figure
> at some point someone's going to stumble across it and download it to see
> what it is.  If you don't want to be serving it, it's probably best to
> not put it up
> on an unprotected web server where people can get to it.  ^_^;
> Speaking purely for myself in this manner, as a random user who sometimes
> sucks down random files left in unprotected directories, just to see what they
> are.
> Matt
> (now where did I put that antivirus software again...?)

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