When planning large installations of IPCheck Server Monitor, there are several parameters to take into account that influence the maximum number of Users/Servers/Sensors that can be monitored using one single installation.

Memory Usage

Per user you must supply about 5 KB of RAM. Per sensor you must supply about 5 KB of RAM without the recent history graphs and about 10k with recent history graphs enabled. Sample calculation:

• 1000 users with 5 sensors each
• 1000x5kb plus 5x1000x10kb => 55 MB RAM

Note: To keep system performance up, this memory should be physically accessible at any time to avoid slow pagefile swapping!

CPU Load

A monitoring load of 30 requests/s (about 2.000 requests per minute) creates a CPU load of about 20% on a 2 GHz Intel machine. With an agressive configuration we would recommend not to cross 40-50% CPU load (e.g. to save CPU cycles for the webserver) which gives us about 5.000 requests per minute, preferrably using a multi processor machine. Sample calculation:

• 1000 users with 5 sensors each with an interval of 1 minute
• 5x1000 = 5.000 requests per minute

BTW: By simply allowing the users a minimum interval of e.g. 5 minutes this load can be lowered to 1.000 requests per minute, etc.

Network Load

Per monitoring request about 200 bytes of internal communication plus the traffic for the sensor (from a few bytes for a PING up to several kb for an HTTP request) is transferred. Using an average of e.g. 1 kb per sensor request a monitoring of 5.000 requests per minute creates a bandwidth load of about 100-150 kb/s.

Plus, the traffic of the webserver, which is tiny compared to this.

Applies to: Version 4 or later