is it possible to use DefaultDispatcher's pool as netty worker pool to avoid context switches? Not s...

# ktor

[enleur]

is it possible to use DefaultDispatcher's pool as netty worker pool to avoid context switches? Not sure if it's a big deal anyway, but still?

[cy]

It is possible only in ktor for now and makes sense only if you are launching coroutines on the default dispatchers

[cy]

all call handlers are running on netty's pool

[cy]

however there are two dispatchers in netty and call handlers are always redispatches by default to guard against users who are running blocking code in handlers

[cy]

To eliminate this context switch you can use option shareWorkGroup

[enleur]

It is possible only in ktor for now

you mean CIO Engine?

[cy]

No, I mean that you can't modify it as we use netty's thread pool for dispatching

[enleur]

as far as I understand, shareWorkGroup will still use NettyWorkerPool instead of DefaultDispatcher

[cy]

Yes, but there is no need to do this unless you launch something on the default dispatcher

[enleur]

I have plenty of switches to IO context and it would be nice to avoid switch to another thread

[cy]

shareWorkGroup = true should make everything work on the same thread pool. Netty does always pin execution to exact thread so there should be no context switch but redispatch may introduce a delay

[enleur]

ok, i got it. thanks!