View source for Object Container Streaming

'''Object Container Streaming''' ('''OCS''') is the umbrella term for all the technology in [[Star Engine]] that makes a vast seamless universe possible, by which ''[[Star Citizen]]'' (and to an extent ''[[Squadron 42]]'') can provide an extremely large virtual world through which the [[player]]s can move without seeing a loading screen.<ref name="jp">{{Cite Jump Point|title=Developer Feature: The Road to Object-Container-Streaming|volume=7|month=10|startpage=3|endpage=16|accessdate=2020-04-04|author1=Christopher Bolte}}</ref>

Without OCS, things such as a spaceship and its contents for example are tracked by both the player client and the server at all times, which impacts performance.

Client side OCS currently in place means that the ship isn't tracked by the player client but by the server, unless the player goes there in which case the ship starts getting tracked on your client side as well.

Planned server side OCS won't track the ship on the client nor server side unless the player goes there, which is the best for server performance as it positively impacts latency, stability, synchronization, and performances such as AI responsiveness.

The servers not having to load everything all the time is essential to allow an expanded game area with more planets, moons, stations, systems etc without loading screens.

==Related technology==

=== Server-Side Object Container Streaming ===

Server-Side Object Container Streaming (SOCS) is a streaming technology needed to expand the scale of the universe on ''Star Citizen'' servers.<ref name="pt39">[https://youtu.be/tcMtPKSe2g4 Star Citizen: Pillar Talk - Alpha 3.9]</ref> The basic concept is that if no player is near an object, the game can "freeze" that object's state. And instead of keeping the frozen entity in memory (incurring a cost), the game can serialize (using Serialized Variables) its state and store the serialized state in a database. While a client is moving through the virtual world, the server updates its view into the database to restore entities now in proximity as well as free and store away no-longer-needed entities.<ref name="jp"/>

==== Entity Streaming Manager and StarHash ====

StarHash is used to store in-game entities in a way allowing efficient searches for all entities in an area of space by utilizing a data structure called a RadixTree. The Entity-StreamingManager is then the logic-driving the StarHash-RadixTree queries to trigger loading and unloading of entities on the server, based on the positions of all connected clients.<ref name="jp"/>

==== Cross Session Persistence ====

Cross Session Persistence allows the game to store the entity in a frozen state in an in-process database that can be used by different server or machine. It is an efficient network access layer to allow the storing of the entity in a database on a different machine. Before Cross Session Persistence, the state of an entity is lost when the server crashes or is restarted (besides the state the game already persist). With Cross Session Persistence, object state will persist over server restarts and crashes (until the persistence database is [[wipe]]d).<ref name="jp"/>

===== I-cache =====

I-cache is a back-end system and service that provides and manages reliable persistence of all player and entity data.<ref name="pt39"/> First major part of I-cache was completed and tested internally in March 2019. It was introduced as a replacement of the existing pCache. It is a highly distributed and fault-tolerant storage/query engine that greatly out-performs pCache. It provides an indexing and query system that can be utilized by other services for specific and complex item queries.<ref name="mrmar19">{{Cite RSI|url=https://robertsspaceindustries.com/comm-link/transmission/17036-Star-Citizen-Monthly-Report-March-2019|text=Monthly Report - March 2019|int=Comm-Link:Monthly Report - March 2019|accessdate=2020-05-25}}</ref>

==== Server Meshing ====

[[Server meshing|Server Meshing]] is a technology that allows the game instance to utilize multiple servers. Instead of having a single server manage all the views, the game will distribute the individual views over multiple servers. Doing this will reduce the load on each participating server. When those servers are placed on different machines on Amazon Web Services (AWS), the game can easily scale with the [[player count]].<ref name="jp"/> The first version of this technology is static server meshing, to be followed by dynamic server meshing which will allow to dynamically mesh server nodes together and then scale the mesh [[Server meshing|dynamically]] based on demand.<ref>{{Cite RSI|url=https://robertsspaceindustries.com/comm-link/transmission/18397-Server-Meshing-And-Persistent-Streaming-Q-A|text=Server Meshing and Persistent Streaming Q&A|accessdate=}}</ref>

=== Network Bind Culling ===