Redis WATCH MULTI EXEC by one client

Question

I am using NodeJS + Express + Redis on RedisOnGo + node_redis as a client. I expect a lot of concurrency, so trying to test WATCH. This example won\'t contain Express, just

Answer 1

If you want to use transaction/atomic MULTI operations but you want to do so using a shared connection, as far as I know your only option is using LUA.

I use LUA scripting within redis for a number of things, and the thing with LUA is the whole script will execute atomically, which is quite convenient. You have to be aware though that this means if you have a slow LUA script you are making redis slow for everyone using your server.

Also, when using LUA even if you can operate on different keys, be aware if you use more than one key in your script you won't be able to use Redis cluster once it is released. This is due to, when using a cluster, keys will be distributed to different Redis processes so your LUA script might not have access to all of them on a single server.

In any case, the problem with redis cluster would be the same when issuing a MULTI, since MULTI won't be allowed to set different keys on a cluster.

Cheers,

j