Re: Memory requirements for web-project

On Sun, Feb 04, 2001 at 05:10:21PM +0100, some SMTP stream spewed forth:
> Hello pgsql-general,
>
> i need to calculate the memory requirement if i am using apache+pgsql.
>
> Lets assume that i want 160.000 hits a day and pgsql takes 3 seconds
> to work for each client, how much ram is required specially for pgsql?
>
> I think I have to calculate the memory requiremend for a specific time
> period.
>
> 160.000 hits are wanted, so I calculate 160.000 div 24 = approx 6666
> Hits a hour, div 60 = 111 Hits a minute, = 1,85 Hits per secound.

Is it safe to preume that most of those 160,000 hits will come during
some relatively short peak period? You could end up with 5-10 hits per
second depending on the usage trends.

>
> lets round it up to 2 hits per secound. So I calculate now
> 2 hits per second * 3 seconds for a client
> = 6 processes at the same time,
>
> is that correct?

It seems correct to me.
>
> If so, how much is the memory requiremend? I have seen with "TOP" that
> pgsql requires 5000kb for a request, but it is used per client (new processes for
> each new client-request?)

Required memory would include Apache plus any modules (PHP, mod_perl,
cgis, etc.), postgres executible *and* whatever memory postgres requires for
processing the query (this may depend on what the user is doing...the
"type" of hit). Don't forget about caches and shared memory also.

gh

>
>
> --
> Boris
> www.x-itec.de
>
>