L4D Server Performance, Cheats - 11/9/08

When Valve gives you lemons, use sv_cheats 1 to fight against four Tanks, dozens of Infected and just as many Boomers. That's our motto in the newest video, showing a battle against the horde where I get tortured by the Infected players in our server. There's some framerate issues in busy spots but you'll get the general idea.

Valver Chris Green asked the HLDS mailing list about L4D server performance:

What are people's perceptions so far in terms of the performance and memory impact of hosting L4D servers, especially compared to our other games? What numbers of full servers have people been able to host on what hardware/os combinations? Internally, when we tried to push as many servers as possible on 8-core xeons, we tended to run out of ram before we ran out of CPU.

Quite a few server owners responded and it was very positive, following are some excerpts:

The CPU usage is unbelievably lower. I know there was a warning that L4D was more CPU-intensive that TF2 (not sure if that was slot-per-slot, or full-server-per-full-server), but in our experience the performance improvements have trounced that several times over. On out setup (Intel(R) Xeon(R) CPU X3210 @ 2.13GHz) a full TF2 server takes up 70% of a core. Each of our 5* L4D servers is taking up 20% maximum right now. -Philip Cass

On my Xeon machine the 5 L4D servers consume about the same as 1 26slots TF2 server.

Your guys are not going to believe this but ... I'm running a l4d server on a Celeron 220 (1.3 Ghz monocore) with 512 MB of ram ... The server is running fine with ~50% CPU usage max. Players are not experiencing any kind of lag or what ever...

Great job to the guys at Valve working on the L4D dedicated server, lower requirements mean cheaper dedicated servers for all of us and therefore more servers to play on!

Searching through the cvar list we found z_common_limit which is default 30. We asked Mike Booth the what and why of this cvar and he responded with the following explanation:

z_common_limit is the master limit on the number of simultaneous zombies. If you increase this number, the Director will allow more zombies to be active at once. There are other cvars that control maximum and minimum mob sizes. The values have been chosen based on game design and playtesting, but also based on hardware performance data from our system surveys. While your machine may be able to handle more zombies at once, that’s not true for everyone. Plus, 30 zombies makes a good, solid, horde.

French L4D fansite L4D.fr has posted a triple screen setup for L4D which you can see below.

The resolution is 3840x1024 and you can see screenshots on their website. Finally, GiantRealm believes L4D is quite a game.

For more videos and impressions, head to the forums!