Monotonically Increasing CPU usage for redis proxy

[tomzilla]

Hello

I'm seeing this pattern of increasing CPU usage over time. This is a staging environment and has pretty low traffic. Memory usage was also increasing like this before I set the -m 512 flag. Now memory usage seems to be stable.

We are running mostly HSET and HGET commands within Lua scripts.

First time running twemproxy. Not sure what to expect here.

[TysonAndre]

What OS is this?

What version are you running? Does this happen with the latest release?

What config options are you using for the redis pool?

I don't remember seeing any similar bug reports and have used redis before without issues with 0.5.0.

Do the sylogs say anything interesting, e.g. frequent disconnections? (See help message for how to log)

[TysonAndre]

Memory usage was also increasing like this before I set the -m 512 flag. Now memory usage seems to be stable.

Currently, twemproxy maintains a free list manually, and doesn't release memory (e.g. if there are spikes in latencies). This is a problem I've seen before - I was considering an approach to free values in batches periodically in a future releases.

[TysonAndre]

See #553 for memory