3 ms·

How you would suggest to demonstrate visually that there are no trade-offs? The tradeoff the way I see it - one needs to implement 200 Redis commands from scra

How you would suggest to demonstrate visually that there are no trade-offs? The tradeoff the way I see it - one needs to implement 200 Redis commands from scratch. Besides, I think DF has a marginally higher 50th percentile latency. Say, if Redis has 0.3ms for 50th percentile, DF can have 0.4ms because it uses message passing for inter-thread communication. 99th percentiles are better in DF for the same throughput because DF uses more cpu power which reduces variance under load. Re-durability - what durability is offerred by Redis? AOF ? We will provide similar durability guarantees with better performance than AOF. We already provide snapshotting that can be 30-50 faster than of Redis.

pcthrowaway 4y ago
Does Dragonfly have a timeseries extension? Or does it support extensions?
- romange 4y ago
  It does not. If you refer to Redis Modules we are not planning to support those - we can just implement same features within DF.
baobob 4y ago
There is usually a tradeoff between latency and throughput, although I'm not so sure this would be true for your innovation, since you've eliminated a whole chunk of fixed overhead from the system (syscall batching). However, batching in general often implies added latency If I recall ScyllaDB has some excellent examples of demonstrating this particular tradeoff visually. A simple option would be a scatter plot where X = latency, Y = load or similar, with points coloured according to the system under test. Probably there is a better option, but this would likely be enough to sell me at least
- romange 4y ago
  Well in that case, I hope to have an good answer for you. Right below the benchmark graph I deliberately put a table that shows 99th percentile lantencies at *peak* throughput as reported by memtier_benchmark. 99th latency percentile of Dragonfly at its peak throughput. I put it here as well op r6g c6gn c7g set 0.8ms 1ms 1ms get 0.9ms 0.9ms 0.8ms setex 0.9ms 1.1ms 1.3ms
- lclarkmichalek 4y ago
  There are also things that are unmitigated improvements.

pcthrowaway 4y ago

Does Dragonfly have a timeseries extension? Or does it support extensions?

romange 4y ago
It does not. If you refer to Redis Modules we are not planning to support those - we can just implement same features within DF.

baobob 4y ago

There is usually a tradeoff between latency and throughput, although I'm not so sure this would be true for your innovation, since you've eliminated a whole chunk of fixed overhead from the system (syscall batching). However, batching in general often implies added latency If I recall ScyllaDB has some excellent examples of demonstrating this particular tradeoff visually. A simple option would be a scatter plot where X = latency, Y = load or similar, with points coloured according to the system under test. Probably there is a better option, but this would likely be enough to sell me at least

romange 4y ago
Well in that case, I hope to have an good answer for you. Right below the benchmark graph I deliberately put a table that shows 99th percentile lantencies at *peak* throughput as reported by memtier_benchmark. 99th latency percentile of Dragonfly at its peak throughput. I put it here as well op r6g c6gn c7g set 0.8ms 1ms 1ms get 0.9ms 0.9ms 0.8ms setex 0.9ms 1.1ms 1.3ms
lclarkmichalek 4y ago
There are also things that are unmitigated improvements.