[wp-hackers] Forum post: Huge server hits

[Jason A. Hoffman]

On Jul 12, 2005, at 10:46 AM, Podz wrote:
> Denis de Bernardy wrote:
>
>>> We do get questions about server load in the forums and we are -  
>>> as yet - unable to give definitive answers.
>>>
>> I disagree. If WP-cache isn't enough for a user, he should be  
>> considering a
>> hardware solution. Not a software solution.
>>
>
> and as someone who answers these, how do I know what the answer is  
> before they go ahead and break things ?
> What /is/ an answer ?
>
> P.

As a quickie:

OK, so 5e6 hits/day(day/24hours)(hr/60mins)(min/60sec) = 58 requests/ 
second

And then there's no concurrency consideration there. Should it handle  
large linked-by-the-BBC-slashdot kind of stuff?

Basically a standard Apache install on a single server won't do that.

Taking it static would allow that that kind of req/second no problem,  
as long as there isn't a persistent concurrency more than 10-50ish.

Then let's think that query-wise (going to assume nothing query  
cached to have an a grossly overestimated upper limit) it's 10-20  
queries/request. So MySQL could be doing ~1200 queries/second (100  
million a day).

For example, weblog.textdrive.com is on a commodity piece of Dell  
hardware (a 2850) that retails for about US$7500 and is on a 100Mbps  
network drop (and gigabit switch/router), we run lighttpd and php- 
fastcgi, and do a decent amount of mysql query caching, and kernel- 
level tuning of FreeBSD.

Fully dynamic our "weblog" can do about 30-40 reqs/second and  
concurrencies up to about 600 (the concurrency is a function of how  
many php-fastcgi processes one has running, this is with 4, running  
20 wouldn't be a big deal). When we involve a static cache, it's  
about 500-600 req/second (and this is a test over a network). That's  
keeping loads less than 1 (can do 20 or 30 before there's semi- 
noticeable lags) etc.

So someone wants a site that does 5-10 million dynamic hits a day,  
and be able to do 10-100x # of visitors-at-a-given-time bursts  
without issues? Then yeah, hardware wise, it's more than one server.  
Network wise, for a 100kb front page, someone can do the math on that.

- J