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Streaming Cassandra at WePay

wecode.wepay.com

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Re: Streaming Cassandra at WePay

#41

Post by dillonmckay »

_cairn wrote: post #13
voidfunc wrote: post #9

Earlier quoted context omitted.

What's your point? Your comment comes off as dismissive and incomplete. Why was the juniors suggestion bad? It may have totally been a garbage suggestion, but if it was explain the reasoning.

Not the author of the relevant post but assuming he's tailing off of the first response I can only surmise they meant that in their case Kafka was unnecessary/a bad choice due to the restraints posed (<5 minute delay, streaming input, etc). Agree that without context it's an incomplete comment that does come off as dismissive, ("junior dev") seems to be meant as belittling/insulting.

Seemed like the wrong solution to the problem.

I apologize to anybody I have offended.

I was hoping for some discourse here.

Re: Streaming Cassandra at WePay

#42

Post by squirrelly »

chucky_z wrote: post #18
benjaminwootton wrote: post #17

Curious if you also looked at Aurora over Cassandra being as you are in the AWS ecosystem? We are an AWS aligned consultancy who are seeing lots of take up of Aurora as it’s MySQL API compatible but with better performance and fully managed. There’s an interesting pattern here using Lambda for CDC between Aurora and Redshift, though not sure how the cost would scale at WePay scale https://aws.amazon.com/blogs/big-dat…

Aurora and Redshift do not scale well enough for companies at their scale (only 64TB for Aurora last I checked, and Redshift falls over near the 100TB level). They'd be looking at DynamoDB.

> Redshift falls over near the 100TB level.

This is based on what? They have stated in various presentations that they have customers using 1pb clusters.

Re: Streaming Cassandra at WePay

#43

Post by gunnarmorling »

benjaminwootton wrote: post #17

Curious if you also looked at Aurora over Cassandra being as you are in the AWS ecosystem? We are an AWS aligned consultancy who are seeing lots of take up of Aurora as it’s MySQL API compatible but with better performance and fully managed. There’s an interesting pattern here using Lambda for CDC between Aurora and Redshift, though not sure how the cost would scale at WePay scale https://aws.amazon.com/blogs/big-dat…

Out of curiosity, is the binlog accessible on Aurora/MySQL? We've lots of users of the Debezium MySQL connector on AWS, but would be interesting to know whether it'd work with Aurora, too.

(Disclaimer: I'm the lead of Debezium, which is the open-source CDC platform to which WePay are contributing their Cassandra work)

Re: Streaming Cassandra at WePay

#45

Post by chucky_z »

squirrelly wrote: post #42
chucky_z wrote: post #18

Earlier quoted context omitted.

Aurora and Redshift do not scale well enough for companies at their scale (only 64TB for Aurora last I checked, and Redshift falls over near the 100TB level). They'd be looking at DynamoDB.

> Redshift falls over near the 100TB level. This is based on what? They have stated in various presentations that they have customers using 1pb clusters.

In my personal experience.

There's a re:invent presentation of them having an in-house 1pb+ cluster. What they don't tell you is that 101 8xl nodes is half a million dollars a year in reserved instances, before you include any other costs associated with it; and that particular workflow (log scanning) is very nicely suited for any columnar store.

Operations are also a disaster with Redshift; anything where you have to touch the cluster itself at any scale past a handful of nodes typically requires a support ticket with "hey, when this breaks, please work your magic and fix it?" There's also the issue of tuning your queues, which is a whole extra layer that you, the customer, must tune. Their suggestion tools are getting better on that front though.

Just use something else if you have more than a few TB, or you have a ton of time and money to just throw around.

Re: Streaming Cassandra at WePay

#46

Post by squirrelly »

chucky_z wrote: post #45
squirrelly wrote: post #42

Earlier quoted context omitted.

> Redshift falls over near the 100TB level. This is based on what? They have stated in various presentations that they have customers using 1pb clusters.

In my personal experience. There's a re:invent presentation of them having an in-house 1pb+ cluster. What they don't tell you is that 101 8xl nodes is half a million dollars a year in reserved instances, before you include any other costs associated with it; and that particular workflow (log scanning) is very nicely suited for any columnar store. Operations are also a disaster with Redshift; anything where you have t…

Ha, $500k/year is the amount a salesperson can knock off the cost of Teradata 100TB setup without calling their boss.

As for ops stuff, I guess YMMV. We’ve never had any significant issues. Tuning is the same or less than on-prem systems IME.

Perf is still pretty much unmatched in the cloud, especially perf/$. Try to do a join on 100tb in a competing system (e.g. BQ) and it won’t finish.

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