Hi we re using ktor websockes

Question

Hi we re using ktor websockes and for client it s multiplatform android iOS our users are 50 android 50 iOS but we noticed that android clients gets disconnected re connected more often than iOS underlined session count indicate that android session are 3 time more than iOS Also the session duration is short 5 seconds our user app session is 2 3 minutes here is server config ```install WebSockets pingPeriod = Duration ofSeconds 20 timeout = Duration ofSeconds 20 maxFrameSize = Long MAX VALUE masking = false ``` and here is client config ```install WebSockets pingInterval = 30 000 ``` I m looking for configuration to stabilise the connection longer session duration without affect real time advantage and see why android is not as stable as iOS any recommendation is using a one minute ping interval safe

Cherrio LLC · Answer

Do you know the cause of disconnection Also I remembered we switched to CIO as engine don t remember why though but it helped to stabilize connection

Christos Malliaridis · Answer

As Ayodele mentioned its worth looking into the causes of the disconnections I could imagine that Android lifecycles may disconnect your clients when the app is thrown into the background e g when the user switches for a short time to another app to answer to a message The behavior may vary between Android devices and versions so analyzing this data may also be valuable

Ahmed na · Answer

< Cherrio LLC> < Christos Malliaridis> Server erros shows ping timeout this why i thought i might need to tweak it a bit can i use CIO for server only or have to be both server and client ```java io IOException Ping timeout at io ktor websocket DefaultWebSocketSessionImpl$runOrCancelPinger$newPinger$1 invokeSuspend io ktor websocket DefaultWebSocketSession kt 279 at io ktor websocket DefaultWebSocketSessionImpl$runOrCancelPinger$newPinger$1 invoke at io ktor websocket DefaultWebSocketSessionImpl$runOrCancelPinger$newPinger$1 invoke at io ktor websocket PingPongKt$pinger$1 invokeSuspend io ktor websocket PingPong kt 86 at kotlin coroutines jvm internal BaseContinuationImpl resumeWith kotlin coroutines jvm internal ContinuationImpl kt 33 at kotlinx coroutines internal ScopeCoroutine afterResume kotlinx coroutines internal Scopes kt 33 at kotlinx coroutines AbstractCoroutine resumeWith kotlinx coroutines AbstractCoroutine kt 102 at kotlin coroutines jvm internal BaseContinuationImpl resumeWith kotlin coroutines jvm internal ContinuationImpl kt 46 at kotlinx coroutines DispatchedTask run kotlinx coroutines DispatchedTask kt 104 at io netty util concurrent AbstractEventExecutor runTask io netty util concurrent AbstractEventExecutor java 174 at io netty util concurrent AbstractEventExecutor safeExecute io netty util concurrent AbstractEventExecutor java 167 at io netty util concurrent SingleThreadEventExecutor runAllTasks io netty util concurrent SingleThreadEventExecutor java 470 at io netty channel nio NioEventLoop run io netty channel nio NioEventLoop java 503 at io netty util concurrent SingleThreadEventExecutor$4 run io netty util concurrent SingleThreadEventExecutor java 997 at io netty util internal ThreadExecutorMap$2 run io netty util internal ThreadExecutorMap java 74 at io ktor server netty EventLoopGroupProxy$Companion create$lambda 1$lambda 0 io ktor server netty NettyApplicationEngine kt 288 at io netty util concurrent FastThreadLocalRunnable run io netty util concurrent FastThreadLocalRunnable java 30 ```

Christos Malliaridis · Answer

If your client is not your server at the same time they are completely independent from one another and they could even be implemented in different programming languages as long as they use the same protocol of communication in that case websockets To answer your question you are completely free to change the engine on client and server side as long as the selected engine supports websockets see <https ktor io docs http client engines html limitations|Ktor Engines Limitations> A ping timeout usually occurs if the server does not receive a pong response from the client in time This may be an indicator that the client is not implemented correctly or that the client disconnects under specific circumstances e g app lifecycle changes