AppSignal VS Memcached

Continuous monitoring of your app's WebSocket performance metrics using tools like AppSignal is your friend here. Reusing the ActionCable consumer on the client side is also advisable, as it will prevent wasting Pub/Sub connections.

Once you've successfully deployed your Sinatra app, you can easily use Appsignal's Ruby APM service. AppSignal offers an integration for Rails and Rack-based apps like Sinatra.

APM tools like AppSignal also provide a convenient dashboard to monitor all your outgoing ActionMailers and keep an eye on deliverability.

Finding information in logs is a painful activity. Developers often blame themselves for not including more information about errors or how to search and filter. If you are not using any monitoring tools that provide this, including meaningful data could save you in the foreseeable future.

It can be tricky to keep an eye on the performance of your database without any other tools. Using AppSignal, you can easily track how your databases perform. See our AppSignal for Ruby page for more information.

The most important consideration with scalability is to identify bottlenecks in an application before we can act on them. A good performance monitoring tool can help. If you need one, check out AppSignal for Ruby.

Read more about AppSignal for Ruby.

Performance/Monitoring - https://appsignal.com/

Memcached

> Multiple clients racing can't be fixed.

Really? You can't think of a single way for multiple clients to operate on the same data without racing? (Here's a hint if you're still having trouble: https://github.com/memcached/memcached/wiki/Commands#cas.)

Memcached: A simple, open-source, distributed memory object caching system primarily used for caching strings. Best suited for lightweight, non-persistent caching needs.

Oh, thank you! I didn't realize that LRU Maintainer Thread was more than an expiration reaper. When it was first being introduced that was its first responsibility as lazy expiration removal by size eviction meant dead entries wasted capacity. It was all work in progress when I had read about it [1] and talked to dormando, so it got fuzzy. The compat code [2, 3] might have also thrown me off if I only looked at the setting and not the usage. Its a neat variant to all of these ideas.

[1] https://github.com/memcached/memcached/pull/97

stores session state in a session store like Memcached or Redis.

memcached has recently gained the ability to spill to disk: https://github.com/memcached/memcached/wiki/Extstore

we recently implemented this to grow our caches to >50TB

Django supports using Memcached as a cache backend. Memcached is a high-performance, distributed memory caching system that can be used to store cached data across multiple servers.