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by daniele_dll 1373 days ago
If I might ask, as I guess from your comments you are using Redis or a compatible platform, which are your numbers? Specifically I am referring to number of servers / vms for Redis, total core count, total memory available, total memory usage.

Thanks!

1 comments

I don't understand this comment in relation to your previous one at all, then.

You said:

Redis can easily chew 200k GET RPS on an average low-core count VM, even if an application does 10 Redis queries per request in average it would still take 20k requests to saturate it... which is an HUGE amount if we think that this would require easily between 50 and 100 machines beefy machines!

Which says you estimate 50-100 machines to saturate one "low-core count VM" Redis. But now you say you meant 50-100 machines for Redis servers?

We run about 20 machines, perhaps the equivalent of 10 "beefy machines", to handle a ~50k/sec request load (with substantially higher peaks). We have less than 100 servers total, most of which are doing asynchronous data processing and not directly in the request pipeline. Our data storage architecture is not really comparable to redis in terms of request load as it's insert/upsert-dominated but the total size is 5-10TB.

Let me answer and then give you some background for my question.

> Which says you estimate 50-100 machines to saturate one "low-core count VM" Redis. But now you say you meant 50-100 machines for Redis servers?

No, I was referring to machines running business logic functionalities using Redis as part of their processing pipeline.

Said that, the reason for which I was asking for some numbers was to figure out if my expectation of "very often you need more room for the data than better performance" was making sense.

Because cachegrand will be able to store data on disk and to handle stream writes as well allowing to leverage the time series db, once fully implemented, it will able to cover a number of different needs. This combined with the ability to run Webassembly means that you will also be able to run whatever you want directly in place and data will not have to go out and in from multiple systems to be processing making the pipelines much faster and cheaper to run.

Of course it doesn't take 1 day, especially because I am working on cachegrand during my free time (e.g. At night or over the weekends).