Varnish VS Memcached

Varnish Cache is a tool that provides a caching HTTP reverse proxy in order to accelerate your web applications. Once Varnish Cache is installed in front of any server that understands HTTP and configured to cache the contents, delivery speeds are typically enhanced by a factor of 300-1000x, depending on architecture. Kilobyte22 finds this tool along with HAProxy to be a winning combo.

In this case, caching mechanism is situated in the proxy server or reverse proxy server like Nginx, Apache, or Varnish, and most probably it is a part of ISP (Internet Service Provider).

To handle this level of traffic, you can use tools such as Varnish HTTP Cache, which caches the information of a news article starting from the first user who accesses and makes the request. Once Varnish caches the page, subsequent users will receive a response that is saved in memory. This process allows you to avoid unnecessary synchronous requests and send a quick response to users.

A couple of dedicated server-side resource caching solutions have emerged over the years: Memcached, Varnish, Squid, etc. Other solutions are less focused on web resource caching and more generic, e.g., Redis or Hazelcast.

VARNISH

Edge Side Includes (ESI): a more modern alternative to SSI. ESI can handle variables, have conditionals, and supports better error handling. ESI is supported by caching HTTP servers such as Varnish.

For this objective, I am looking for willing volunteers to run through two phases of test deployments. These phases will each involve creating a scalable Varnish Cache cluster on Azure Kubernetes Service and answering a few questions about your experience. The deployments should take a total of around 30 min (or less) and will require the creation of a very minimal Kubernetes cluster. For some more information on Varnish Cache check out: https://varnish-cache.org/

For reads, caches are the primary tool, such as Varnish or memcached.

Others have pointed out some very valid issues. A quick hack, try using Varnish Cache (https://varnish-cache.org/), you can really accelerate the static content delivery.

In this case, caching mechanism is situated in the proxy server or reverse proxy server like Nginx, Apache, or Varnish, and most probably it is a part of ISP (Internet Service Provider).

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.