Correction: current default client MaxConcurrentStreams is 1,000 <https://github.com/golang/go/blob/c99687f87aed84342cfe92ae78924f791237c6f6/src/net/http/h2_bundle.go#L7208>
On Friday, September 14, 2018 at 4:47:27 PM UTC-5, Eddie Shvartsman wrote: > > Greetings! > We are seeing a problem at high RPS where repeated http2 calls using the > same Transport (reusing as recommended > <https://golang.org/src/net/http/transport.go> in go docs) are exceeding > the server's MAX_CONCURRENT_STREAMS setting, resulting in a protocol > error. The server appears to be setting MAX_CONCURRENT_STREAMS to 100 as > indicated in this http2 debug output... > > 2018/09/13 11:18:04 http2: Framer 0xc42037b180: wrote DATA > flags=END_STREAM stream=1 len=0 data="" > 2018/09/13 11:18:04 http2: Framer 0xc42037b180: read SETTINGS len=30, > settings: HEADER_TABLE_SIZE=4096, MAX_CONCURRENT_STREAMS=100, > INITIAL_WINDOW_SIZE=65535, MAX_FRAME_SIZE=16384, MAX_HEADER_LIST_SIZE=16384 > 2018/09/13 11:18:04 http2: Transport received SETTINGS len=30, settings: > HEADER_TABLE_SIZE=4096, *MAX_CONCURRENT_STREAMS=100*, > INITIAL_WINDOW_SIZE=65535, MAX_FRAME_SIZE=16384, MAX_HEADER_LIST_SIZE=16384 > ... > 2018/09/13 11:18:49 http2: Transport encoding header "content-type" = > "application/json" > 2018/09/13 11:18:49 http2: Transport encoding header "content-length" = > "1547" > 2018/09/13 11:18:49 http2: Transport encoding header "accept-encoding" = > "gzip" > 2018/09/13 11:18:49 http2: Transport encoding header "user-agent" = > "Go-http-client/2.0" > 2018/09/13 11:18:49 http2: Framer 0xc42037b180: wrote HEADERS > flags=END_HEADERS stream=17191 len=56 > 2018/09/13 11:18:49 http2: Transport readFrame error on conn 0xc420418e00: > (http.http2ConnectionError) connection error: PROTOCOL_ERROR > 2018/09/13 11:18:49 http2: Framer 0xc42037b180: wrote GOAWAY len=8 > LastStreamID=0 ErrCode=PROTOCOL_ERROR Debug="" > > If we reduce the RPS to <100, the error does not occur. > > My modest understand of the protocol and how the go http client *should* > work is that the client and server negotiate MaxConcurrentStreams. My read > of the code is that the client's default is 250 streams; however, that > should be negotiated down to 100, given this is the maximum the server > supports (is that right?). My understanding of current behavior is that the > client should block if MaxConcurrentStreams is exceeded. > > Any insights or help would be greatly appreciated. > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
