This reduces allocs and bytes used per log entry significantly as well
as some improvement to time per log operation.
Each log driver, however, must put messages back in the pool once they
are finished with the message.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Upstream-commit: 3f4fccb65f0ef286c9c4e0f01c4ae7bb09a6ad89
Component: engine
This allows the user to set a logging mode to "blocking" (default), or
"non-blocking", which uses the ring buffer as a proxy to the real log
driver.
This allows a container to never be blocked on stdio at the cost of
dropping log messages.
Introduces 2 new log-opts that works for all drivers, `log-mode` and
`log-size`. `log-mode` takes a value of "blocking", or "non-blocking"
I chose not to implement this as a bool since it is difficult to
determine if the mode was set to false vs just not set... especially
difficult when merging the default daemon config with the container config.
`log-size` takes a size string, e.g. `2MB`, which sets the max size
of the ring buffer. When the max size is reached, it will start
dropping log messages.
```
BenchmarkRingLoggerThroughputNoReceiver-8 2000000000 36.2 ns/op 856.35 MB/s 0 B/op 0 allocs/op
BenchmarkRingLoggerThroughputWithReceiverDelay0-8 300000000 156 ns/op 198.48 MB/s 32 B/op 0 allocs/op
BenchmarkRingLoggerThroughputConsumeDelay1-8 2000000000 36.1 ns/op 857.80 MB/s 0 B/op 0 allocs/op
BenchmarkRingLoggerThroughputConsumeDelay10-8 1000000000 36.2 ns/op 856.53 MB/s 0 B/op 0 allocs/op
BenchmarkRingLoggerThroughputConsumeDelay50-8 2000000000 34.7 ns/op 894.65 MB/s 0 B/op 0 allocs/op
BenchmarkRingLoggerThroughputConsumeDelay100-8 2000000000 35.1 ns/op 883.91 MB/s 0 B/op 0 allocs/op
BenchmarkRingLoggerThroughputConsumeDelay300-8 1000000000 35.9 ns/op 863.90 MB/s 0 B/op 0 allocs/op
BenchmarkRingLoggerThroughputConsumeDelay500-8 2000000000 35.8 ns/op 866.88 MB/s 0 B/op 0 allocs/op
```
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Upstream-commit: 054abff3b67bb5d66323e5418a43c845a3eac8a1
Component: engine
