UnrealIRCd performance and limits

UnrealIRCd can handle thousands of locally connected clients just fine. On multi-server networks the total amount of users is virtually unlimited. Clients are spread over multiple servers for better performance and increased resilience against server and network outages.

See also:
 * FAQ: How many users can UnrealIRCd handle
 * FAQ: How much CPU and memory do I need

Below are the limits explained in detail, as of UnrealIRCd 5.0.9 and later.

Other limits
Many other limits are actually "soft limits" that can be freely changed on-the-fly in the configuration file. These are limits imposed to control abuse, spam and flooding. Almost all these limits are in the Set block. For example, set::maxchannelsperuser controls how many channels may be joined by every user.

One of the limits that is not in the set block is maxperip, which controls how many connections are allowed per IP address. This is done in the Allow block.