To Serverless
and Beyond
Dor Laor, Co-founder & CEO

Why ScyllaDB?
We asked the smartest entity on earth

ScyllaDB

ScyllaDB

ScyllaDB

ScyllaDB

Why ScyllaDB?
Best High Availability in the industry
Best Disaster Recovery in the industry
Best scalability in the industry
Best Price/Performance in the industry Auto-tune - out of the box performance
Fully compatible with Cassandra & DynamoDB
The power of Cassandra at the speed of Redis
No Lock-in
Open Source Software

■ Quick recap for newbies
Agenda
■ Journey of 2022
■ The Future of Fast Data

ScyllaDB Journey Gen #1:Brute Power

Database Scores
Database Efficiency Score =
ƒ(query/vcpu, workload/ram, cost/storage);
Database Over Provision Score =
ƒ(idle, tables/clusters, readonly/DCs);
Database Scale Score =
ƒ(10x scale cost/ability,P99@Scale,Time2scale,Ease of scale);
Database Maintenance Score =
ƒ(Backup,Repair, Replace,Scale, Upgrade,Observe,Trace);
Database Freedom Score =
ƒ(License, Environment, Ecosystem tools);

R1
Can I
propose a
value?
Check
condition
R2
R3
Accept
new value
Learn
decision
Decision made
o
k
!
o
k
!
r
o
w
c
h
e
c
k
s
u
m
o
k
!
a
c
k
ok!
ScyllaDB Journey Gen #2:Full API, LWT

ScyllaDB Journey Gen#3:
CDC,K8S,Indexes,ICS,Alternator

ScyllaDB Journey - ScyllaDB 5.0
ScyllaDB Cloud 2022 Roadmap
Today (2022) - Perfect Single Tenant land
■ Extreme efficiency
■ Perfect security & isolation
■ Clear and simple units - servers
■ > 5x Cost effectiveness vs all others
■ Easy to consume

ScyllaDB Journey - ScyllaDB 5.0
ScyllaDB Cloud 2022 Roadmap
Today (2022) - Perfect Single Tenant land
■ Extreme efficiency
■ Perfect security & isolation
■ Clear and simple units - servers
■ > 5x Cost effectiveness vs all others
■ Easy to consume
Coming - Multi tenancy
■ Separation of compute & storage
■ Serverless, pay per usage
■ Elastic w/ APIs control
■ More efficient than today’s
implementation
■ Preserves ScyllaDB goodware™

■ Quick recap for newbies
Agenda
■ Journey of 2022
■ The Future of Fast Data

2022:
All Weather,
All Terrain,
High Throughput,
Low Latency Database

■ Performance, performance Isolation, performance
■ Maintenance, Maintenance, Maintenance
■ Consistent metadata by Raft
■ ScyllaDB Cloud serverless - abstract the servers
2022 Highlights

■ IO Scheduler v5
■ Per partition rate limit
■ 30% CPU gain coming to
enterprise/cloud
■ Distributed aggregates
■ Eliminate exceptions
from the IO path
■ Reverse queries
■ I4i
■ Range tombstone v2
Performance, Performance Isolation

■ v1 max-io-requests
■ V2 bandwidth+iops
capacity, statically
partitioned
■ V3 cross-shards
capacity sharing
■ V4
rate-limiter-based
capacity
■ V5 Mixed BW
I/O Scheduler V5

■ v1 max-io-requests
■ V2 bandwidth+iops
capacity, statically
partitioned
■ V3 cross-shards
capacity sharing
■ V4
rate-limiter-based
capacity
■ V5 Mixed BW
I/O Scheduler V5

■ v1 max-io-requests
■ V2 bandwidth+iops
capacity, statically
partitioned
■ V3 cross-shards
capacity sharing
■ V4
rate-limiter-based
capacity
■ V5 Mixed BW
I/O Scheduler V5

■ v1 max-io-requests
■ V2 bandwidth+iops
capacity, statically
partitioned
■ V3 cross-shards
capacity sharing
■ V4
rate-limiter-based
capacity
■ V5 Mixed BW
I/O Scheduler V5
Also added per I/O class throttling
■ Compaction
■ Repair
■ Streaming

■ IO Scheduler v5
■ Per partition rate limit
■ 30% CPU gain coming
to enterprise/cloud
■ Distributed
aggregates
■ Eliminate exceptions
from the IO path
■ Reverse queries
■ I4i
■ Range tombstone v2
Performance, Performance Isolation
SELECT COUNT(*) FROM keyspace.table
Return c1
Return c2
Return c3
COUNT )
p0..p1
COUNT )
p2..p3
COUNT )
p4..p5
COUNT )
p6..p7

■ IO Scheduler v5
■ Per partition rate limit
■ 30% CPU gain coming
to enterprise/cloud
■ Distributed
aggregates
■ Eliminate exceptions
from the IO path
■ Reverse queries
■ I4i
■ Range tombstone v2
Performance, Performance Isolation
7
1
2 5
7
1 2 5

■ IO Scheduler v5
■ Per partition rate limit
■ 30% CPU gain coming
to enterprise/cloud
■ Distributed aggregates
■ Eliminate exceptions
from the IO path
■ Reverse queries
■ I4i
■ Range tombstone v2
Performance, Performance Isolation

■ Performance, performance isolation, performance
■ Maintenance, Maintenance, Maintenance
■ Consistent metadata by Raft
■ ScyllaDB Cloud serverless - abstract the servers
2022 Highlights

■ Auto Tombstone GC
■ Load & stream
■ Auto restore
■ RBNO
■ Consistent Schema
changes
Maintenance, Maintenance, Maintenance

■ Auto Tombstone GC
■ Load & stream
■ Auto restore
■ RBNO
■ Consistent Schema
changes
Maintenance, Maintenance, Maintenance
1-333
334-666
667-1000
1-200
201-400
401-600
601-800
801-1000
201-400
1-200

■ Auto Tombstone GC
■ Load & stream
■ Auto restore
■ RBNO
■ Consistent Schema
changes
Maintenance, Maintenance, Maintenance
Repair Based Node Operations is in for /all /default
■ Resumable
■ Consistent
■ Simplified
■ Fast
■ Unified

Top-K Queries
User defined aggregates = UDF +
WASM +
Distributed aggregates +
Workload prioritization
How many people follow Elon Musk?
What are the top-k products in shopping carts

Double Click on Database Drivers
■ Maintain Python, Java, Go
■ Huge boost w/ Rust
■ C++ driver, wrapped over Rust
■ Improved load balancing (shard, cache, zone aware)
■ Serverless support
■ Performance

■ Performance, performance isolation, performance
■ Maintenance, Maintenance, Maintenance
■ Consistent metadata by Raft
■ ScyllaDB Cloud serverless - abstract the servers
2022 Highlights

■ Raft
■ Consistent Schema
changes
■ Consistent topology
changes
Consistent Metadata by Raft
Protocol for state machine replication
Total order broadcast of state change commands
Single leader
X = 0 X += 1 CAS(X, 0, 1)
X = 0

■ Raft
■ Consistent Schema
changes
■ Consistent topology
changes
Consistent Metadata by Raft
RAFT
Safe
schema
changes
Safe
topology
changes
Dynamic
partitioning
Consistent
tables
Tablets
5.0
5.2
5.3

■ Performance, performance isolation, performance
■ Maintenance, Maintenance, Maintenance
■ Consistent metadata by Raft
■ ScyllaDB Cloud serverless - abstract the servers
2022 Highlights

■ Quick recap for newbies
Agenda
■ Journey of 2022
■ The Future of Fast Data
■ Serverless
■ Core ScyllaDB

s/server/vcpu/

■ Abstract the servers, instances. Building block is VCPU
■ Decouple storage from compute. Still uses NVMe
■ Flexibility of annual commit
■ Encryption@rest + BYOK
■ Elasticity
■ API & Terraform
■ Advanced Network gateways
■ Self serve user management & SSO
■ Self serve billing & metering
Scylla Cloud Goes Serverless

Vision
Old: The power of Cassandra at the speed of Redis
New: The power of ScyllaDB, with the usability of DynamoDB

Gamechanger Revolution
Today
■ Eventual consistency
■ 3x replication, may not be identical
■ Storage is bound to compute
■ Full scan repair process is required
■ Cheap for high throughput,
expensive for high volume
Future
■ Raft based consistency
■ No need to repair
■ Single main replica, on S3
■ Can be cached for performance
■ Save arriving, fresh data in 3 replicas,
until sync w/ S3
■ Point in time recovery, extreme
elasticity
■ Cluster parking
■ ~Free disaster recovery backup

Future of Key Ranges
■ token = hash(partition key)
■ token range: set of partition keys
token
token
range
token

Each node has a set of tokens assigned during bootstrap
Token Metadata - vNodes
node A node B node C
A
C
B
C
A
B

Token Metadata - vNodes
A
C
B
C
A
B
{A, C}
{C, B}
{B, A}
{C, A}
{A, B}
{B, C}
token
metadata
replication
metadata
replication
strategy

Future of Key Ranges
Today
■ Key ranges =~ vNodes
■ Statically allocated @node
creation
■ Size of TBs
Coming - Tablets
■ Small range of keys
■ Size GBs-10GB
■ Dynamically controlled
■ Dynamically mapped/moves
between nodes

Tablets
tablet
tablet
replica
tablet
replica
tablet
replica
replication
metadata:
(per table)

Tablets - Balancing
Aim at manageable size:
■ Not too small -> few -> low
metadata overhead
■ Not too large -> many ->
enough to balance load

Tablets - Balancing
The load balancer can decide to
move tablets

Tablets
Resharding is cheap.
SStables split at tablet boundary.
Reassign tablets to shards (logical operation).

Tablets
Cleanup after topology change is cheap.
Just delete SStables.

Today
■ Disaggregated, local NVMe
■ Gravity - time to stream
■ Ultra fast
■ Cheaper than EBS/SAN
■ Expensive if not queried
Future of Storage

Future of Storage
tablet
replica
tablet
replica
Node
Node
Node
Node
Node
Node
Node
Nodes w/ NVMe are awesome!

Future of Storage
tablet
tablet
replica
tablet
replica
Node
Node
Node
Node
Node
Node
Node

Today
■ Disaggregated, local NVMe
■ Gravity - time to stream
■ Ultra fast
■ Cheaper than EBS/SAN
■ Expensive if not queried
Object Store / S3 based
■ $ almost free
■ Completely decoupled
■ Fully consistent
■ Accessed by all nodes
■ Tiered Storage
■ Slow-> Local NVMe cache
Future of Storage

Future of Storage
tablet
Node
Local
write
Send
commitlog
Upload
S3
Repair &
compact

Future of Storage
tablet
Node
■ Compaction can happen off-query engine
■ Sstables NVME-cached by replicas (Cache-Replication-Factor)
■ Tiered Storage helps to control size of NVMe cache
■ Available for all users (not just DBaaS)

Tablet +
S3 +
Raft Metadata
= G.O.A.T

G.O.A.T Future
tablet
Node
■ Data in S3 - Low TCO
■ NVMe Configurable Caches == Fast, tiered storage
■ Elasticity
■ Remove nodes - Sync pending to S3 & change table ownership
■ Add nodes
■ many at once
■ New hardware added async from tablet ownership
■ Node can serve data from the first tablet assigned!
■ Get the local NVMe cache populated
■ Point in time Backup/restore
■ Add/remove data-centers easily - access local S3
■ Cluster parking

Future of Consistency
Eventual
Consistency
Immediate
Eventual
Consistency

Bring RAFT to user tables!
CREATE TABLE foo WITH raft = TRUE;
Strongly-Consistent Tables
Do not have any databases
before ScyllaDB.
Always run nodetool cleanup
after bootstrapping a new
node.
Run repair within gc-grace
seconds.
Do not bootstrap nodes
concurrently, or make
any other topology change
Do not use SimpleStrategy in
a multi DC setup
Do not have any databases
before ScyllaDB.
Always run nodetool cleanup
after bootstrapping a new
node.
Run repair within gc-grace
seconds.
Do not bootstrap nodes
concurrently, or make
any other topology change
Do not use SimpleStrategy in
a multi DC setup
Do not have any databases
before ScyllaDB.
Always run nodetool cleanup
after bootstrapping a new
node.
Run repair within gc-grace
seconds.
Do not bootstrap nodes
concurrently, or make
any other topology change
Do not use SimpleStrategy in
a multi DC setup
Do not have any databases
before ScyllaDB.
Always run nodetool cleanup
after bootstrapping a new
node.
Run repair within gc-grace
seconds.
Do not bootstrap nodes
concurrently, or make
any other topology change
Do not use SimpleStrategy in
a multi DC setup

Strongly-Consistent Tables
LWT (paxos based)
■ Slow
■ 3 rounds to replicas per user
request
■ Concurrent conflicting requests
-> retries -> negative scaling
RAFT
■ Fast
■ 1 round to replicas (on leader)
■ No retries

2022 ScyllaDB is great
Welcome to Serverless
Welcome to the Future
Thank You
@DorLaor