Re: [HACKERS] Re: Re: re : PHP and persistent connections

At 05:26 PM 11/25/00 -0700, Ron Chmara wrote:
>Note: CC'd to Hackers, as this has wandered into deeper feature issues.
>
>Tom Lane wrote:
>> GH <grasshacker@over-yonder.net> writes:
>> > Do the "persistent-connected" Postgres backends ever timeout or die?
>> No.  A backend will sit patiently for the client to send it another
>> query or close the connection.
>
>This does have an unfortunate denial-of-service implication, where
>an attack can effectively suck up all available backends, and there's
>no throttle, no timeout, no way of automatically dropping these....
>
>However, the more likely possibility is similar to the problem that
>we see in PHP's persistant connections.... a normally benign connection
>is inactive, and yet it isn't dropped. If you have two of these created
>every day, and you only have 16 backends, after 8 days you have a lockout.
>
>On a busy web site or another busy application, you can, of course,
>exhaust 64 backends in a matter of minutes.

Ugh...the more I read stuff like this the more I appreciate AOlserver's
built-in database API which protects the application from any such
problems altogether.   The particular problem being described simply
can't occur in this environment.




- Don Baccus, Portland OR <dhogaza@pacifier.com>
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  Rare Bird Alert Service and other goodies at
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