IllegalStateException writing to Redis

[Daniel López]

Hi,

We had yesterday some kind of hiccup when writing to Redis, and even though we are still investigating what might have caused it, the error being thrown is not telling us much and we wonder if it might ring a bell for you :).

The important pieces of the stack trace are:

...

Caused by: com.lambdaworks.redis.RedisException: java.lang.IllegalStateException at com.lambdaworks.redis.LettuceFutures.await(LettuceFutures.java:106) at com.lambdaworks.redis.LettuceFutures.awaitOrCancel(LettuceFutures.java:74) at com.lambdaworks.redis.cluster.StatefulRedisClusterConnectionImpl$ClusterFutureSyncInvocationHandler.handleInvocation(StatefulRedisClusterConnectionImpl.java:343) at com.google.common.reflect.AbstractInvocationHandler.invoke(AbstractInvocationHandler.java:87)

...

Caused by: java.lang.IllegalStateException at com.lambdaworks.redis.output.CommandOutput.set(CommandOutput.java:63) at com.lambdaworks.redis.protocol.RedisStateMachine.lambda$safeSet$289(RedisStateMachine.java:178) at com.lambdaworks.redis.protocol.RedisStateMachine$$Lambda$115/1445992401.run(Unknown Source) at com.lambdaworks.redis.protocol.RedisStateMachine.safeSet(RedisStateMachine.java:195) at com.lambdaworks.redis.protocol.RedisStateMachine.safeSet(RedisStateMachine.java:178) at com.lambdaworks.redis.protocol.RedisStateMachine.decode(RedisStateMachine.java:118) at com.lambdaworks.redis.protocol.CommandHandler.decode(CommandHandler.java:162) at com.lambdaworks.redis.protocol.CommandHandler.channelRead(CommandHandler.java:141) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:307) at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:293) at io.netty.channel.ChannelInboundHandlerAdapter.channelRead(ChannelInboundHandlerAdapter.java:86) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:307) at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:293) at io.netty.channel.ChannelInboundHandlerAdapter.channelRead(ChannelInboundHandlerAdapter.java:86) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:307) at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:293) at io.netty.channel.ChannelInboundHandlerAdapter.channelRead(ChannelInboundHandlerAdapter.java:86) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:307) at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:293) at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:840) at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:131) at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:511) at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:468) at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:382) at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:354) at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:112) at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:137)

Can you think of a circumstance that would throw such exception?

Thanks,

D.

PD: Using Lettuce 4.1.Final against a cluster of Redis

[Mark Paluch]

Hi Daniel, 

that sort of exceptions can appear if the connection gets out of sync - if a Redis response does not match the expected command response. In that case, lettuce received an integer value and expected something different.

I've seen such exceptions in combination with reconnects. I fixed some issues with lettuce 4.2.1, maybe you want to upgrade the driver. 

Cheers, 

Mark