User:Thinker/GenericBuffering

A lot of features in Gecko require some kind of buffering; for ex., Camera, media playing back, WebRTC, Animation, ... etc. But, there is no generic buffering framework in Gecko. Every module implements its-owned buffering. The pro is getting better performance due to fully customized for the task. The cons are hardly for adapting, studying, analyzing, and porting. So, we need a framework for buffering that is easy to customize for performance, adapt to different configurations and applications, easily analysis it, port to various platforms, and a common language/slang among modules.

Buffering

There are several factors should be considered for buffering/queuing.

• queue size
• queue management
• queuing discipline
• synchronization
  • ack
  • nak
• threading
• servers
  • the service function
  • the number of servers
• Buffer management

union QueueManagementType { QMT_DEFAULT, QMT_RED, QMT_TAIL_DROP };
union QueueDisciplineType { QMT_FIFO, QMT_LIFO, QMT_PRIO };
union MsgSyncType { MST_NONE, MST_ACK, MST_NAK };
union QueueThreadingType { MST_NONE, MST_THREAD_BEGIN, MST_THREAD_END, MST_THREAD_INDEPENDENT };
union BufferManagementType { BMT_REUSE, MST_UPSTREAM, MST_DOWNSTREAM, MST_PROVIDER };
typedef int (*MsgServiceFunc)(Buffer *inbuffer);
typedef Buffer (*BufferCreatorFunc)(int paylaod_size);

struct QueueConfig {
    const char *qname;
    int qsize;
    QueueManagementType qman;
    QueueDisciplineType qdisc;
    MsgSyncType msync;
    QueueThreadingType qthreading;
    MsgServiceFunc servicefunc;
    BufferManagementType bman;
    BufferCreatorFunc bcreator;  // valid only for bman == MST_PROVIDER
    int numServers;
    int numOutPads;  // Output pads
};

Configuration of Queues

Create and connect queues together.