How to use http keep-alive for OTLP/HTTP

[chinawilon]

I use the OpenTelemetry-Collector as agent co-located with my application, and I found something not meeting expectations!

root@VM-80-2-ubuntu:/data/web# tcpdump -i any port 4318
tcpdump: data link type LINUX_SLL2
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on any, link-type LINUX_SLL2 (Linux cooked v2), snapshot length 262144 bytes
11:47:12.461706 lo    In  IP localhost.4318 > localhost.36454: Flags [.], ack 3353824839, win 512, options [nop,nop,TS val 2230719946 ecr 2230704842], length 0
11:47:12.461718 lo    In  IP localhost.36454 > localhost.4318: Flags [.], ack 1, win 512, options [nop,nop,TS val 2230719946 ecr 2202369654], length 0
11:47:12.717707 lo    In  IP localhost.4318 > localhost.43862: Flags [.], ack 1629484599, win 512, options [nop,nop,TS val 2230720202 ecr 2230705098], length 0
11:47:12.717714 lo    In  IP localhost.43862 > localhost.4318: Flags [.], ack 1, win 512, options [nop,nop,TS val 2230720202 ecr 2214981986], length 0
11:47:12.973740 lo    In  IP localhost.4318 > localhost.54468: Flags [.], ack 298931131, win 512, options [nop,nop,TS val 2230720458 ecr 2230705355], length 0
11:47:12.973752 lo    In  IP localhost.54468 > localhost.4318: Flags [.], ack 1, win 512, options [nop,nop,TS val 2230720459 ecr 2217383604], length 0
11:47:13.741729 lo    In  IP localhost.4318 > localhost.37488: Flags [.], ack 1290580590, win 512, options [nop,nop,TS val 2230721226 ecr 2230706122], length 0
11:47:13.741736 lo    In  IP localhost.37488 > localhost.4318: Flags [.], ack 1, win 512, options [nop,nop,TS val 2230721227 ecr 2167737606], length 0
11:47:13.745693 lo    In  IP localhost.4318 > localhost.35244: Flags [.], ack 1765188201, win 512, options [nop,nop,TS val 2230721230 ecr 2230706123], length 0
11:47:13.745702 lo    In  IP localhost.35244 > localhost.4318: Flags [.], ack 1, win 512, options [nop,nop,TS val 2230721230 ecr 2204772629], length 0
11:47:14.765712 lo    In  IP localhost.4318 > localhost.59602: Flags [.], ack 3169972842, win 512, options [nop,nop,TS val 2230722250 ecr 2230707146], length 0
11:47:14.765722 lo    In  IP localhost.59602 > localhost.4318: Flags [.], ack 1, win 512, options [nop,nop,TS val 2230722250 ecr 2224589987], length 0