MySQL Lists are EOL. Please join:

List:Database Benchmarks« Previous MessageNext Message »
From:Kishore Jalleda Date:March 28 2006 5:54pm
Subject:Re: Chat application and performance
View as plain text  
This is roughly the formula for calculating the minimum memory needed by
mysql

min_memory_needed = global_buffers + (thread_buffers * max_connections)

where thread_buffers includes the following:

sort_buffer

myisam_sort_buffer

read_buffer

join_buffer

read_rnd_buffer

and global_buffers includes:

key_buffer

innodb_buffer_pool

innodb_log_buffer

innodb_additional_mem_pool

net_buffer

So assuming your total database size is not that huge and if your global
buffers include say 100MB (mainly Key buffer Size which is the total of
*.MYI files in your data directory) , and each of your threaded buffers are
say 512KB, then according to the equation

1000MB = 100MB + ((512KB * 4) * max_connections)

which gives you
max_connections = 900MB/2MB ~= 500 concurrent connections ...

but this is just an approximation and you can easily calculate the actual
values depending on your specific requirements .....

Hope this serves as a good starting point .....

Kishore Jalleda


On 3/28/06, Charles A. Landemaine <landemaine@stripped> wrote:
>
> Hello,
>
> I am designing a model for a call center 100% web-based. I don't know
> whether using MySQL of other DB systems, and also I'd like to know, at
> least to have a rough idea how my hardware will behave in front of a
> number of simultaneous connections.
>
> There will be a database dedicated to registering new messages for
> attendants and customers on the call center. This database will
> basically have a few rows (depending on the number of customers
> connected), and it will have pretty much 2 columns: one for the
> customer ID (session), and another column with a flag to tell if there
> is a new message or not.
>
> Each 2 second, each customer who has the chat window open will make a
> query to this light-weight database to see if there are new messages.
> Each attendant also does the same queries each 2 second.
>
> I'd like to have a rough idea how many simultaneous people can use
> this application on a server with an Intel Celeron 2.4 Ghz + 1GB RAM
> running FreeBSD.
> If you have any other opinion, please let me know.
>
> Thanks,
>
> --
> Charles A. Landemaine.
>
> --
> MySQL Server Benchmarks Mailing List
> For list archives: http://lists.mysql.com/benchmarks
> To unsubscribe:
> http://lists.mysql.com/benchmarks?unsub=1
>
>

Thread
Chat application and performanceCharles A. Landemaine28 Mar
  • Re: Chat application and performanceKishore Jalleda28 Mar
    • Re: Chat application and performanceCharles A. Landemaine28 Mar
RE: Chat application and performanceDonald Foss28 Mar