This looks like an issue that has been seen in grpc-go earlier. What types of calls are these - unary? or streaming?
Indeed for unary calls, each call is currently flushing writes after sending headers and status for each call. The message portions of unary and streaming calls (split up into separate http2 data frames if it's large) both have some but only small amounts of batching of syscall.Writes. There has been some work towards reducing this but I think the issue is probably somewhat expected for latest update. (There's one experimental solution to reducing unary call flushes in https://github.com/grpc/grpc-go/pull/973) On Thursday, January 19, 2017 at 1:25:36 AM UTC-8, Zeymo Wang wrote: > > I fork grpc-go uses as gateway just enioy h2c benifit (also remove pb IDL > feature),which I implement 0-RTT TLS( cgo invoke libsodium) repalce the > standard TLS and handle request just do http request to upstream; In > benchmark of bidirectional streaming rpc ,high cpu usage under not much > heavy load (maxConcurrencyStream = 100 or 1000 ,the same), according to "go > tool pprof ", I find syscall.wirte consume much cpu and RT ( maybe cgo > performance?). At least 3 time call system.wrtie (flush) will cause this > problem (header + data + status)?Is orignal grpc have this issue?how to > resolve or reduce invoke syscall.write？or waiting go add syscall.writev? > > > <https://lh3.googleusercontent.com/-0TCAcilsguw/WICDnBBHKBI/AAAAAAAAB_k/2OtJVaBq9ykgXPKboM43S8PWR1OXT59oQCEw/s1600/perf.jpg> > > > <https://lh3.googleusercontent.com/-2HXrQl6GgH0/WICENZODGQI/AAAAAAAAB_o/VUTPcgod4wQsI8Csoh7rVSBwcEe-n3yqQCLcB/s1600/strace.jpg> > > > > > <https://lh3.googleusercontent.com/-IV3cZmIFYso/WICD8niuwnI/AAAAAAAAB_g/liXcah0inB4RQJxujk57SYxfzmjaVCvgQCEw/s1600/pprof.png> > > > > -- You received this message because you are subscribed to the Google Groups "grpc.io" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/grpc-io. To view this discussion on the web visit https://groups.google.com/d/msgid/grpc-io/abd91fd7-f1ff-4b7b-bda6-5cd0a3a13018%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
