168 karma · joined April 23, 2015
The problem for startups is that debt provider who are also a bank require to move most of the business to that provider. It's not the case other types of debt providers. w.r.t debt - everybody use this mechanism, doesn't matter if you're small or big.
The JVM is part of the problem, not all of it. The main issue is that it hides the hardware and makes tracing harder - instruction level and block level. At Scylla we strive for efficiency, every operation is tagged with a priority class for the CPU and I/O schedulers. Folks are welcome to read the blogs about those topic. Lots of details and hard work
- Comcast moved from 970 Cassandra nodes (and 60 nodes of cache) to 78 Scylla nodes - https://www.scylladb.com/2020/01/15/comcast-sprinting-from-c...
- Palo Alto Networks run 8600 clusters(!) of ScyllaDB https://www.scylladb.com/2022/06/14/how-palo-alto-networks-r...
ScyllaDB excels in throughput and latency, we have also a better compaction algorithm that saves 37% of storage compared to C*. Usually one can replace lots of small nodes with gigantic nodes that have more resources and it allows much better management.
To run 100PB Scylla will need more than 300 nodes, even thousands but definitely not what Apple throw at the problem.
The whole intent is to make it a learning experience, if you wish to reproduce, try it yourself. It's aligned with past measurements of ours and also with former Linux optimizations by Marc.
Some K/V workloads are affected by the networking stack and we recently seen issues if we chose not the ideal interrupt mode (multiqueue vs single queue in small machines)
It's not 'fair' to compare CQL to SQL, if you compare CQL to DynamoDB's http api, which scylla implements as well, you'll see that cql is better: https://www.scylladb.com/2020/05/12/comparing-cql-and-the-dy...
The right way to use NoSQL is when you know your scaling model. LWT helps you to serialize important tables.
Scylla consistently makes improvements in operations, consistency and functionality, so more to come, see what we'll announce at the summit next month
Recently we have a MSc project to add Parquet which is a very good direction, couldn't agree more.
We could stack 100k rows in a single partition and be 1000x faster in this use case than the performance we demonstrate but we wanted to keep it real. Actually the use case we wanted to show is a single row per partition which would require more machines but surprisingly we couldn't provision that many on AWS.
The presented usecase by ClickHouse is 100x slower on writes (8M row/s) as they report. It doesn't matter since it's just a completely different use case. Use Clickhouse for analytics (I wonder why stop in SSE and not to go all the way to the GPU like SqreamDB) and use Scylla for OLTP
At first I (disclosure, ScyllaDB co-founder) called their serverless a bluff but I gave it a try and it's nice to create a table without waiting for any server. That said, I know personally that Dynamo scales really slow so they wouldn't catch up the speed. It also say 1 digit ms latency but state the plan to improve jvm overhead.
Another funny thing is (regardless of tech) that AWS folks have wonderful people talking about open source but this very solution isn't open at all. It's impossible to figure out what's Cassandra and what's Dynamo. How about a diagram?
Lastly, it's pricey (for 1M iops you'll pay $3.5M/year!!) and doesn't have counters, UDT, materialized views and plenty other features.
If you got down here, hey, give ScyllaDB a try, it's OSS (AGPL) and as a service on AWS and has features that neither C* or MCS has - workload prioritization for instance. Dor
- Here's a webinar by one of our customers explaining how they migrated from Mongo+Hive, received better consistency and simplicity while saving 5X: https://www.youtube.com/watch?v=1hXKd_rNyuE
- See how kiwi.com got a CRAZY gain with Scylla vs Cassandra: https://youtu.be/Bqh09LG_QDE?t=833
- See Grab (South east Asia Uber) about Dynamo vs Scylladb: https://www.scylladb.com/users/case-study-grab-hails-scylla-...
Go ahead and give it a try and see for yourself