Server scalability questions

I have questions about server scalability

1) where does the forum put its loads on? is it the web server or the DB server?
2) can we loadbalance webboard with 2 webservers and 1 DB server? is there any cookie/session management problem?


Thanks

1) both. Some smaller tasks can be performed on webserver like caching, sending e-mail, upload, etc, while other tasks on SQL server (stored procedures)

2) It really depends on how your load balancer works. If the load balancer supports the idea of " session affinity" , then it will be just fine. Just keep in mind that our software use both application and session variables, and it scales extremely well (700-1000 active users w/ 10,000+ posts per day without any degradation in performance)

This topic is exactly what I was looking for.


Samuel,

If the web servers are load balanced but are not session aware, would this board be able to support it?

If I turn off session variables, is there a way around it?

Thanks!

Yes you can turn session off because our software supports database based session without using the session object of ASP and ASP.NET. This thread is quite old and when the thread was started, we did not have the ability to do database-based session.

What about two database servers? For redundancy purposes, I have two IIS servers each running SQL 2000. I'm using Windows NLD to manage traffic. My website is a fairly simple ASP app, and I'm using SQL's continuously updating merge replication to keep the two DBs in sync. Will your software work in such an environment? My main reason for doing this is that I want the site to be available while I'm rebooting one of the two servers.

I am unable to say for sure if the software will work in such environment because we never tested it with this configuration. Are there any special requirements in the database design for such configuration? If not, then the software will definitely work.

Samuel,

I have some similar questions:

1) What is the largest implementation of ASPP to date?  In other words, how far has the software been pushed?

2) What if we were expecting daily messages to go to 100,000 - 200,000 and concurrent users to go to 30,000?  Are there any sites out there (beyond just ASPP) that currently handle that kind of traffic?

Thanks for your insight -

JS

The largest I believe is RCUniverse http://www.rcuniverse.com/forum/ (3.3 million posts w/ 2000 concurrent users)

I can't answer your 2nd question because we never have users with that much traffic. You may want to split the forums up into more defined, smaller sections and distribute them over several installations/domains. 100,000 - 200,000 daily posts and 30,000 concurrent users is a lot of traffic for any web application, and may require special hardware configuration.

Thanks Samuel -

Do you have any idea if there are any forums (non-ASPP) out there that deal in numbers like this?  Of course we are being optimistic, and may be overshooting by quite a bit.  We just want to be as sure as we can be that ASPP will be able to scale to handle many times the traffic we are seeing now.

And thank you for the "split the forums up into more defined, smaller sections and distribute them over several installations/domains" idea.  I never thought of doing that.  In that case, could you still maintain a single user profile database table?  In other words, 2 separate installations of ASPP on different domains pointing to the same user profile?

Thanks again -

JS

1) I am sorry that I can't provide info regarding performance of other software. I personally do not know of any message board software capable of handling the load you mentioned (no such data available). I am not saying there isn't one, but whichever you go with, you must have a special hardware setup to handle such high load. You will probably need a dozen front-end web servers and a cluster of SQL servers in order to provide reasonable performance.

2) no, when you split them up, each forum will maintain its own user database.

Thanks Samuel -

JS

One quick follow-up question:

Is there anything programmatically that would prevent ASPP from scaling infinitely?  In other words, is it simply a matter of hardware, or is there a theoretical limit to how far the software can go?

Thanks again -

JS

Hi John,

I want to be as honest as possible with you -> the answer to this question is I don't have a definite answer for you. I built the software with performance as a priority from the ground up, but I still can't tell you if the architecture is flawless. If anyone gives you a definite answer to this question, he is a liar. We do not set any limit in the software, but the limitation can come from the ASP/.NET engine, from the IIS, or from the SQL server, which are all software that our software depends on.

For any software design to be successful, it is paramount that you know your audience. For example, I know for a fact that most people won't have more than 100 forums at a single location (I can say from my experience, 99.9% of the discussion boards on the internet don't have more than 100 forums), so I more or less optimized the software's presentation for situations that have less than 100 forums.

Hi Samuel ;
 
I don't think RCuniverse is the biggest implementation of your software.
 
http://rankings.big-boards.com/?filter=ASP%20Playground,all
 
You see here. Or here ;
 
http://rankings.big-boards.com/?filter=ASP+Playground,all&sort=week
 
We are now doing this with only two servers. One for the web, and one for the sql.
 
We set 20 minutes for the session. RCUniverse set it 45 minutes and we used a distinct IP for guests browsing the site. (Because some browsers do make several concurrent connections that alters the real user)
 
We do see 500-600 members, and 700 guest in a normal day.
 
Software scalability is great. I don't think there will be a limitation. Our SQL server load only about %30 max on a day. That's with Dual Xeon 2.8 Ghz.
 
Also we do use normal news pages in same servers.

The software is also capable of load balancing. But if you enable  user image uploading this will be different story. You have to write little scripts that once a file uploaded  that uploads other web servers. Or you can modify code to centralize image uploading in a single server also using for image distributing.  That make sense because image uploading serving is a time consuming and not top priority for the cpu's. This will seriously decrease cpu usage. Maybe you can think about that in version 3 Samuel.