What is Redis and What Does It Do?

Start learning cybersecurity with CBT Nuggets. courses.cbt.gg...
Trevor Sullivan covers the Redis cache service: what it is, what it does, and how it helps. It's an open source tool that runs as a service in the background that allows you to store data in memory for high-performance data retrieval and storage. That's the technical explanation, but watch on to hear about how useful it is for all manner of use cases.
Imagine you have a web application that's running inside a Docker container or directly on a server. If that web application needs to retrieve some data from a database like MySQL, PostgreSQL or MS SQL, that query could take anywhere between 15 and 60 seconds.
If you have a user waiting up to a minute for the performance of that report data or whatever data the user is trying to receive, you're going to have an unhappy user. A redis cache speeds all that up.
It's possible to store data inside of a Redis cache instance and make the retrieval of that data occur directly from memory (RAM) from a server that's running the Redis service - rather than making the application go all the way back to the database. Instead, the web server can check with Redis if it has the data it wants.
Redis isn't particularly valuable when it's standing in-between one web server and a database. But, what if you're running a large scale fleet of hundreds of webservers? One Redis cache can pool the requests and answers for all those webservers so that they don't have to individually go all the way to the database each time.
📁 Download the Ultimate Sysadmin Cert Guide: blog.cbt.gg/2c97
⬇️ 4-Week Study Plan: MD-100 & MD-101: blog.cbt.gg/k0q7
Start learning with CBT Nuggets:
• Intro to Cloud Computing | courses.cbt.gg...
Not a CBT Nuggets subscriber? Start your free week: www.cbtnuggets...
-----------------
Connect with CBT Nuggets for the latest in IT training:
• Twitter - / cbtnuggets
• Facebook - / cbtnuggets
• Instagram - / cbtnuggets
• LinkedIn - / cbt-nuggets
#redis #docker #mysql #ittraining #cbtnuggets

[@pinxtr]

My man looks like he's putting tutorials straight from Antarctica

[@opossum4463]

He looks like the CEO of a certain fortune 500 company. And that can't be a bad thing.

[@opossum4463]

I mean, minus the nose ring.

[@samarth319]

I think he looks pretty similar to Twitter's CEO Jack Dorsey...

[@kw19991]

This is why indexes were invented, to reduce retrieval time for a query.

[@ekanastone]

I thought u were Jack Dorsey at firsts lol

[@hangout7081]

😂 me too

[@musaopaluwa2580]

🤣🤣🤣🤣

[@mdbasaz]

Me too

[@akeinchina]

lol, me too.

[@user-td5gy2fh3p]

Lmfaooooooooo 😂😂😂

[@riskitall7421]

Awesome explanation Trevor. Breaking down problems into dummy understanding is an art.

[@lajos108]

I started a LinkedIn course on Redis, just to see what is it about. After 20 minutes I started to search on UA-cam for a summary of Redis and get the meaning of it in short time. This explanation is short, understandable, just great. Thanks!

[@kinax2]

What if the user has updated he is info, Would the user get an old data or new data?

[@kaushikdr]

I have to admit, I was initially distracted by your glorious beard! :D
I have a few questions I hope you can clarify -
1) Why is querying Redis faster than directly querying a database - is it because there is less amount of data to search from? Also, at what point does the cache start removing data? Is the oldest data removed first or is it the data that is accessed least often?
2) If we are using a cache worker to update the Redis cache every time there is a change to the database, why is this any faster than just directly querying the database? It seems that in this case, the Redis cache contains the same amount of information as the database and that the database would be updated before the Redis cache anyways.

[@courageahorttor7666]

Awesome elaboration. He hit the nail straight to the point

[@Ferruccio_Guicciardi]

Redis In-Memory database ! Redis Cache Service ! .... mmm... interesting.

[@RedisUniversity]

Couldn't have put it better, great work!

[@lil_soum]

You did such a great job explaining this, thank you.

[@juneldomingo6277]

Great explanation! wonder what will happen to traffic if the redis goes down? will the web goes down as well as it cant retrieve data from cache? or will the web traffic will go directly to the database. Thanks

[@PowerUsr1]

This is a really good video. I’m a network engineer playing with docker and I’ve seen this a few times. Always wondered what it is.

[@Paul_Aderoju]

Thank you so much. Heard Vercel recently implemented a Key-Value system, and it’s a Redis-like data system. This video gave me a good overview of Redis.

[@ThefamousMrcroissant]

Aha, so basically an in memory cache. Very well structured video; shows the problem and how Redis attempts to solve it, making it intuitive to grasp its purpose.

[@deedoodeedoo6382]

@Alek Wolf I'm a complete beginner at Redis, but this seems to be a general software problem. Since Redis is an in-memory app that strives to use cache, to decrease the wait time for common data queries, it is based on RAM usage. Since it is based on RAM usage, it's limited by the RAM provided with the machine. I don't think BigData ever was a viable target for usage of Redis. BigData can return huge responses to queries and it's not really feasible to hold it all in limited RAM, a few bigger reports and OOM is achieved. I suppose at that point a better approach would be putting in resources to speed up the access to BigData resources and optimizing queries.

[@adityamittal4357]

This isn't what redis is, this is just an explanation of how a cache works. Caching is just one use case for redis. This video will make beginners think that redis is a cache, which is false. Redis is an in-memory key-value store with pub-sub model with many use cases such as creating event streams in architecture beyond mere caching.

[@rednejiv123]

Excellent video! Thanks a lot.

[@osmangani4966]

simple and clear, to the point.......really like the way you explain.

[@jackcastro9583]

i agree with your thinking！🥤cheers🥤

[@RoshanakRahimi-d1p]

thank you, it was so helpful

[@rohitschauhanitbhu]

I really liked the video. But your face could be a little smaller as all my attention keeps getting diverted to the beard, in all seriousness.

[@Acumen928]

Just what I needed.

[@koders9778]

This was very helpful. Thanks sir!

[@cbtnuggets]

We're so glad it's helpful for you! Thank you for learning with us.

[@2dapoint424]

Ohh so this is why Jack Dorsey quit Twitter!! To teach redis ,🤪

[@StrikerEureka85]

FINALLY! a clear explanation as to what it actually does. thank you for this.

[@xxxxxGhostBoyxxxxx]

the beard is an indicator of experience

[@darrenklein6090]

Thanks, that was very helpful.

[@kunalb2051]

Best video on Redis ❤️

[@chriskaye1997]

Truly a great beard, so wow! much wisdom!

[@MrPx0727]

Very good in explaining Redis serving as a cache system; would be nice to expand to all important features of Redis ...

[@androidsavior]

where is the next video ? i cant find it

[@jackcastro9583]

hey brother ， Your beard is sexy, i love it😀

[@adrianalb4098]

really ... what web application would run queries that take 30 seconds to execute ... in any database engine ? maybe 30ms.
yet, redis has his use, no doubt.

[@IchEsseKonsolen]

Liking for the adorable outro. It HAS been informative for me!

[@LooneyTunesCarrot32]

So does this mean that the redis caching service will only be a hit if there has already been an existing query on the DB?
Also, will the cache itself ever get too full, then what?

[@krishnashah6654]

Store data in a redis cache instance and retrieve that data from the RAM of the server that’s running the service.
Initially the instance doesn’t have any data instead of it’s config data.

[@TANRININresulu]

Trade off made from correctness of retrieved value hence it is a cache…

[@angeloreyes707]

Anybody else turn on the Captions to see how wrong the AI is about what he's saying? lol. Amusing.

[@byteestudio6406]

Hie Guys. My name is Jack Dorsey😅😅🤣🤣😂😂

[@alexandroskourtis5268]

greeeaaat video

[@amanuelyohannes7151]

I read somewhere redis is a great use case for chat apps. How does that be inline with caching I am very confused

[@moonman239]

So Redis can improve scalability by caching data.

[@姚瑶-q8w]

very clear explanation. make us impressed a lot.

[@aakarshanraj1176]

01:20 the query wont take 30s if made by a user since its most of the time OLTP

[@curtezyt1984]

YETI?

[@novicecoder5753]

The explanation is good but can you give a real life example

[@mridulranjan1069]

So this video is about seeing your overgrown beard and not really redis :-/

[@frogman3107]

Why do we need database when we can store everything in redis in the first place?

[@dmitrykim3096]

I mean I guess this cache is only good if the data is quite small or we always request thr same data

[@nicklowe_]

I’m not totally clear how the amount of RAM allocated to a docker instance would be able to hold any substantial amount of data from a database. I understand how this is useful for commonly queried data, but wouldn’t the service have to be very selective in what it chooses to cache? And don’t we have to worry about available RAM for the web server? Does Redis ever battle the server for resources?

[@none0n]

Thanks for the great explanation. So in order words, without a cache workers, redis won't be aware of new data and there is always the risk to fetching stale data?

[@Ibrahim-oc5ql]

very informative. thanks gistalot

[@i3looi2]

So why not do the caching at server/api level ?

[@Kirimoshi]

I like the way you explain things, please keep going 👍

[@leedy8135]

why always introduce ? is it impotant?

[@Shubham__Saroj]

real quick and awesomely covered in less time.

[@jesseneon1896]

Amazing content but reduce your beards

[@mikkeljensen1603]

save your self the trouble and just use redis as a database, it is amazing

[@lifebyvikk6751]

Oh look. Jack Dorsey got a twin brother

[@levijohansen2603]

can barely see you, please make yourself bigger on screen

[@ShukyPersky]

Sounds interesting
1. What are the memory requirements in the case of a large-scale database to keep this solution effective?
2. How effective this solution for a system that generates random access to a large-scale database?
in which case Redis cache would require a lot of memory to stay effective
I think that these topics should be referred to by the video.

[@cbtnuggets]

Hi Shuky, thank you for your questions.
It will really depend on the load and amount of data, but there are some profiles in AWS and Azure that will be for enterprise requirements up to 14TB of memory. docs.microsoft.com/en-us/azure/azure-cache-for-redis/cache-planning-faq#azure-cache-for-redis-performance This is a good break down of some performance recommendations.
We hope this is helpful! Thank you for learning with us.

[@mohammadzulqarnain6288]

Simple and precise, it made me recall how my fried explained me about Redis and Guava caching but unfortunately i dont recall the difference btw them.

[@adityamittal4357]

This isn't what redis is, this is just an explanation of how a cache works. Caching is just one use case for redis. This video will make beginners think that redis is a cache, which is false. Redis is an in-memory key-value store with pub-sub model with many use cases such as creating event streams in architecture beyond mere caching.

[@an1me.graphics]

bro is a caveman who travelled to the future

[@sandhyakaranam6113]

great explanation , thank you

[@ns4k_tv]

Thanks! Helped me alott!!

[@globalclutter9508]

Very informative.

[@torrvic1156]

Thank you so much! That was very informative! I learned the scenarios of how I can use Redis.

[@abbasabdulsalambamidele8760]

Very well explained. Thanks

[@bsummer]

Wish we all Had Guys like this before College.
Redis, which stands for Remote Dictionary Server cements it

[@tech3425]

Jack dorsey teaching me redis

[@indrranil24]

awesome loved it!!!!

[@horsedevoursy5458]

standard Eugene beer nerd. would be much better less distracting without someones face no matter how they look

[@balu2567]

why is jesus telling me what is redis

[@ranjeetbadhe]

Can you please let us know how the Redis implementation in Openstack Controller works?

[@Joop5037]

Very good explanation.

[@rupeshsingh3607]

Nice video Sir ,please carry on ,nice voice clarity and representation

[@luvon1114]

master node and slave node? ^_-

[@Food.5inder]

Awesome dude... simple and crispy explanation. Keep it up appreciate.

[@davidmunyiri6147]

That's a nice explanation Trevor, i like the way you explained bit by bit to understanding level

[@princekm5902]

where are his ears?

[@SuperKidontheblock]

Sounds alot like directory based caching.

[@jordanpedroinvestimentos]

Good video

[@juejuepaing6985]

Thank you

[@briarsmith8241]

Cache hit on the explanation

[@vishalk2798]

Well i had a query how long does the redis store a cache for is it for days or hours as if the cache does not clear then the redis cache size would get full right

[@gagang.r684]

Thank you. It cleared all my doubts😀

[@tylercode2207]

That was really helpful...Thank You!!

[@michael_ibeh]

you look like Jack Dorsey

[@lovinthumper]

Very informative.

[@ann_uken]

Thank you for your great explanation! 💥

[@Me3rkPL]

I googled CBT Aware

[@baolam4180]

awesome explanation and greatly clear english speaking. I can fully listen to you without looking at the sub. Well done!

[@BassZeke]

Fantastic! concise. clear

[@BlueDolphinBlues]

Hi Trevor Sullivan

[@canyoldas2855]

Very informative. Thank you.

[@navid045]

Very good, great accent

[@workpfeiffer3428]

good explanation. thakns a bunch

[@aparnasaha9729]

excellent explanation

[@sangtengkorak1954]

I see no one is make it, so I'll do.
You know extension of redis name?
Redis what?
Redis nutz
Great video all in all, thanks for the explanation.

[@whatthefunction9140]

Hi Trev

[@diet92]

Well understood 😎. Thanks

[@davidbister2684]

This is like hanna?