Entity limit
From Valve Developer Community
For reasons of memory allocation, there is a limit to the number of entities Source can manage at once.
The combined size (in bytes) of a map's entity data should also be considered, even if the number of entities is within safe limits. Large amounts of entdata can take a noticeably long time to transmit from server to client, and
Confirm:may lead to crashes
Tip:When creating very large or detailed maps, remember that more entities will exist at runtime than were compiled in. Things like weapons held by characters, projectiles and death ragdolls are all entities too. If you see "no free edicts" errors then you need to start cutting!Engine limits
There can be up to 4096 entities. This total is split into two groups of 2048:
- Non-networked entities, which exist only on the client or server (e.g. death ragdolls on client, logicals on server).
- Entities with associated edicts, which can cross the client/server divide.
If the game tries to assign a 2049th edict it will exit with an error message, but if it tries to create a 2049th non-networked entity it will merely refuse and print a warning to the console. The logic behind this may be that an entity spawned dynamically (i.e. not present in the map) but not assigned an edict probably isn't too important.
The two entity lists are created by CBaseEntityList::CBaseEntityList() using NUM_ENT_ENTRIES and MAX_EDICTS. Neither of those values can be changed without breaking compatibility with the engine.
Tip:Temporary entities and static or detail props do not count toward either limit. Tip:If you're creating lots of individual objects all the time, consider rolling them all into a single manager entity. This is how Left 4 Dead handles huge numbers of infected: they are all "finger puppets" of the director. Tip:In-game, use console commands like report_entities and cl_showents to get an idea of how many entities are present at that current state. Tip:The infodecal entity requires an edict since it can be activated to toggle it on and off. If you mod map has heavy use of infodecals, you can change the infodecal entity to a server only entity. This will require the removal of the toggle ability. To do this modify the CDecal parent from CPointEntity to CServerOnlyPointEntity. You will need to comment out the TriggerDecal, and InputActivate functions. Alternatively, you could create a infodecal_toggle entity to preserve both features.Hammer limits
Hammer itself has no entity limit, but VBSP's is 8192. This is double the combined total accepted by the engine, which may be because it at first treats internal entities (such as prop_static and env_cubemap) like normal entities, or perhaps because it generates a lot of detail props.
VBSP also recommends an entdata size limit of 384KB, but this is in no way enforced.
