SendPacket allocated four times per down track write: a 3 byte slice for
abs-send-time, a 2 byte slice for transport-cc, and two appends to a nil
Extensions slice because the pooled header was reset to a zero value.
Give pacer.Packet fixed scratch arrays for the two extensions and marshal
into them. The Packet is pooled and owned by one send until SendPacket
returns, so nothing is shared across down tracks. Keep the pooled header's
Extensions capacity across reuse, both when returning it to the pool and
when a down track initializes it.
Adds a test that asserts zero allocations per SendPacket.
Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>
* Use sync.Pool for objects in packet path.
Seeing cases of forwarding latency spikes that aling with GC.
This might be a bit overkill, but using sync.Pool for small +
short-lived objects in packet path.
Before this, all these were increasing in alloc_space heap profile
samples over time. With these, there is no increase (actually the lines
corresponding to geting from pool does not even show up in heap
accounting when doing `list` in `pprof`)
* merge
* Paul feedback
* Separate from ion-sfu
changes:
1. extract pkg/buffer, twcc, sfu, relay, stats, logger
2. to solve cycle import, move ion-sfu/pkg/logger to pkg/sfu/logger
3. replace pion/ion-sfu => ./
reason: will change import pion/ion-sfu/pkg/* to livekit-server/pkg/*
after this pr merged. Just not change any code in this pr, because it
will confused with the separate code from ion-sfu in review.
* Move code from ion-sfu to pkg/sfu
* fix build error for resovle conflict
Co-authored-by: cnderrauber <zengjie9004@gmail.com>
