>>>>> "Ken" == Ken Williams <[EMAIL PROTECTED]> writes:
Ken> [EMAIL PROTECTED] (Randal L. Schwartz) wrote:
>> It would be pretty simple, basing it on my CPU-limiting throttle that
>> I've published in Linux Magazine
>> <http://www.stonehenge.com/merlyn/LinuxMag/col17.html>. Just grab a
>> flock on the CPU-logging file in the post-read-request phase instead
>> of writing to it. If you can't get the flock, reject the request.
>> Release the flock by closing the file in the log phase.
>>
>> But this'd sure mess up my ordinary visit to you, since my browser
>> makes 4 connections in parallel to fetch images, and I believe most
>> browsers do that these days.
Ken> I was thinking about that too, and concluded that you'd only want to
Ken> throttle the back-end server in a 2-server setup. That would usually
Ken> (save for subrequests) only be 1 request throttled per page-load. I
Ken> tend not to care about the front-end, because overload is rarely a
Ken> problem there.
Well, if the reason you're throttling is to block excessive usage of
the machine, the full monty of CPU limiting will do that just fine,
since images are delivered quickly, but anything that eats CPU starts
pushing the counter up to the max. That's why I have my CPU
throttler, and it worked fine to prevent me from being "slashdotted"
that one day I was mentioned there. I'm told that my CPU throttler
was used at etoys.com for a similar purpose, and permitted them to
keep from losing millions of dollars of revenue due to people
spidering their catalog.
--
Randal L. Schwartz - Stonehenge Consulting Services, Inc. - +1 503 777 0095
<[EMAIL PROTECTED]> <URL:http://www.stonehenge.com/merlyn/>
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