Why is there a restriction on key length?

We also would like to use keys longer than 250 characters.

A longer key name means it takes MORE space to cache things, I would think. Unless you mean there is less available space to cache things, which also isn’t accurate - the space available remains the same, simply the same amount of space can hold fewer items.

Just spent a few hours yesterday discovering this key length restriction myself. Wish it had occured to me that might be it. I spent time figuring out how to get the client to output logging, and all it informed me was that the socket was dead. Unfortunately, it was the very first item I tried to store. If I had happened to store an item with a key shorter than 250 and it worked, and then later a key longer and it didn’t work, i would have honed in quicker on the problem. As it was, the logging for the client made it seem like a socket problem. After attempting to store with a key longer than 250 characters, the (.net) client kills the socket, and all subsequent requests the socket is just dead. So that brings the question of why not just error on that operation, rather than kill the socket completely. Though I guess if it only sporadically didn’t save certain items this would have been a frustrating “sighting” bug, rather than something that I was forced to get to the bottom of and address immediately.

It would be nice if the server returned some error status, rather than the socket just not reading bytes and having it appear that there’s a socket problem, so the client kills the socket.

Any chance that the key length could be something configurable, defaulting to the current limit but able to be explicitly made greater after reading a blurb about why lower length is important?

When you say you cache the most recently used data, do you mean you cache just the keys of the most recently used data? Because if you cache both the key and the value, then the number of most recently used items you are able to cache is going to be much more influenced by the size of the value than by the size of the key. In which case, why not open it up to allow longer keys?

Thanks for your consideration,
-ChssAddct