ἑκατόνby Niko Neugebauer

Niko Neugebauer• PASS Evangelist• SQL Server MVP• SQLPort (http://www.sqlport.com) founder &

leader• BITuga (http://www.bituga.pt) co-founder• 15+ years in IT

HeKATONHEK-A-TON, HEK-A-TON, HEK-A-TON

HekAton• ἑκατόν – means 100 in Greek• Targeted to improve OLTP performance, 100

Times

Conceptionally?• Imagine that you have a number of CPU steps

to perform a typical OLTP action• Optimize it 100 times by removing obstacles

like latches and parallelize it• Yes, you will need start from the bottom and

from the very beginning?

Hardware Trends• Look at the CPU speed increase• Look at the Memory Prices• You can’t buy a SQL Server Enterprise License

for a price of a TB• Think, think, think

New generation DBHekaton

HistorySybase SQL Server

1.0• 1980 (1989)

• Hardware Expensive

• CPU Bound

• Pages 8K

SQL Server 11.0• 2012

• Hardware Cheap

• IO & Memory Bound

• Pages 8K

Hekaton• In-Memory Database• Multi-Core Awareness and Optimizations• xVelocity compression algorithm (hint: ColumnStore)• No Pages (no more splits, allocations, etc)• No Locks, No Latches + different Concurrency Control• StreamInsight (no more 8K’s)• Hash Index (no more b-trees)• Existing T-SQL can be reused

Hekaton• Highly scalable concurrency control

mechanism • Lock-free data structures

Hekaton• ACID compliant• Optimized for extreme Transaction Processing

scenarios like • Financial Services• Online Gambling

• There are customers who are using it NOW

Integrated into the DataBase Engine

Hekaton

Particular Features• Snapshot_Isolation ONLY• No support for LOB data types • No Triggers• AlwaysOn Support

features• Durable Tables• Non-Durable Tables• TempDB is used inside of the Hekaton, in-

memory• Shares memory with Buffer Pool, but has its

own space

Architecture• Different space allocation for memory buffer• The very same transaction log, but with fewer

writes• Different filegroups• Different treatment for Indexes• A lot of new, different stuff

HEKATONIt actually looks like a …

Programability• Create table dbo.Hekaton(

• Id int primary key hash with (bucketcount = 65535),

• Nome varchar(50)) WITH (MEMORY_OPTIMIZED = ON, DURABILITY = SCHEMA_AND_DATA );GO

T-SQLStored Procs:• Uses C as internal intermediate presentation,

and then compiles into native code• Atomic blocks• Can’t reference non-hekaton tables

T-SQL Programability• Create procedure dbo.HekatonNow

• WITH NATIVE_COMPILATIONBEGIN

select name from dbo.Hekaton;ENDGO

Details• Uses StreamInsight• No actual updates, but deletes & inserts

UTils• Migration from the normal DB tables to

Hekaton• Stored Procedures Migration to Hekaton

WHEN ?Next major version of SQL Server

BUT• Isn’t it too fast ? • – No, there is no such concept as too fast. (as

long as it does not create other problems)

Thank you