What is the Traffic Limit?

For a database with max 25 concurrent users

[Buddha]

I have a dynamic website using a database with 25 concurrent connections max.

Does anyone have any idea what the maximum # of visitors I can have per day with this database?

[Reflect]

You can exceeed, I am assuming Access, it just slows down the query results to the DB.

Take care,

Brian

[Buddha]

Actually, the database is MSDE 2000

[Reflect]

Sorry, I was feeding off the 25 concurrent statement.

Take care,

Brian

[mattur]

As long as there are fewer than 25 concurrent users (or perhaps more accurately, page requests) at any one instant, there won't be a problem.

Imagine 26 users visiting the site: at any one instant some will be making page requests, some will be reading content, some will be deciding where to click next etc. As long as all 26 users don't simultaneously* make a page request, your web site will be able to handle the load.

Website traffic tends to be unevenly distributed throughout the day. So to work out whether MSDE will scale to support your traffic, you need to look at the busiest periods on your site, not number of visitors (or page requests) per day.

Simply put: 1,000,000 page requests a day distributed evenly over 24 hours is a different load to 1,000,000 page requests a day when all 1,000,000 requests occur in one second.

*I'm ignoring processing time for simplicity: if your data access code takes 100ms, as long as you get fewer than 25 page requests in any given 100ms your site will cope. There are other factors to take into account e.g. connection pooling and queuing. To get an accurate measure of max page requests per second you need to use a web server load testing tool.

[Lord Majestic]

Actually, the database is MSDE 2000

MSDE is crippled, and I don't think the limit is 25 concurrent connection. Here is quote from MSDE home page:

"As more batch workloads are submitted beyond the five-workload limit, the concurrency governor continues to slow down the system. These workloads are not dropped or lost; they are still processed, but in an increasingly degraded performance mode."

Your original question lacks details - it all depends on what kind of queries you run, this can be as low as 10ms and sky is the limit to queries with poor performance - I've seen code that took seconds to run to get data for webpage, certainly not acceptable unless users expects low performance (big report).

MSDE was designed to prevent successful usage in multi-user environments, particularly webserving - hence restrictions on concurrent workloads. If I were you I'd explore MySQL.

I've done my share of performance testing and my advice to you will be to load test your website - this will show bottlenecks and give some conrete figures for your configuration. There are free load testing tools on the Net - run a few searches. This will give you good answer for your config.

[Buddha]

Thanks everyone for your feedback.

I actually started running some stress tests using various tools yesterday.

Also, I took log data from our busiest hour of the busiest day of the year to find a rough estimate of the max number of concurrent users we had.

Right now, I want the performance of the website to be under 2 seconds at 3X the max number of concurrent users we expect.

For my traffic patterns and my website, MSDE would slow greatly at about 35K visitor sessions per day.