Sizing Guidance

For guidance on hardware sizing refer to the Genesys Sizing Calculator. The Genesys Sizing calculator helps you evaluate resource utilization based on your requirements and make the proper hardware choice.

Important

For more sizing related information and resources, refer to the Genesys Sizing Tools System Level Guide. Also, refer to the Genesys Orchestration Platform chapter in the Genesys Hardware Sizing Guide.

Orchestration Persistence - System Configuration and Storage

Orchestration Persistence is not commonly used, but this section provides you some sample guidelines to help understand the factors that must be considered in terms of system configuration and Cassandra sizing when persistence is enabled.

Consider a contact center with around 4.5 million interactions per year, 250 working days a year, and 12 business hours a day. That will approximately work out to around 25 interactions per minute. For this minimal traffic, the following basic system configuration is recommended:

• three nodes for a quorum
• each node with 8GB for the JVM
• multiple cores (2+)
• local secondary storage

Tip

It is good to have more number of cores as Cassandra is CPU intensive, especially during the compaction process.

Sample Disk Space Storage Calculation

The following disk space storage calculation table provides a sample estimate for:

• 5000 active sessions with session persistence enabled,
• average session JSON size of 45K,
• and 2 Cassandra nodes with a replication factor of 2.

NR (Number of Rows)	Assumes 5,000 active sessions	5,000
NC (Number of Columns) - per Row	1 for Session, 2 for SessionIDServerInfo	3
CNS (Column Name Size) - in bytes	UTF(8)	8
CVS (Column Value Size) - in bytes	Average of 45K for a session	45,000
RKS (Row Key Size) - in bytes		50
RF (Replication Factor)		2
Number of Nodes in Cluster		2
IPS (From column_index_size_in_kb in YAML file)		64
TNC (Total Number of Columns)	NR*NC	15,000
Column Data (Amount of actual data in your cluster)	TNC*CVS	675,000,000	45,000 (CVS)
Column Overhead	TNC*(15+CNS)	345,000	23 (15+CNS)
Column Subtotal	Column Data+Column Overhead	675,345,000
Row Header Overhead	NR*(23+RKS)	365,000	73 (Row Header Overhead/NR)
Row Bloom Filter	NR*((2+8)+CEILING+((((NC*4)+20/8),1))	70,000	14 (Row Bloom Filter/NR)
Row Index	(4+(IF((CEILING(((Column Subtotal/NR)/IPS),1)>1),CEILING(((Column Subtotal/NR)/IPS),1),0)*((CNS*2)+20)))*NR	380,000,000	76,000 (Row Index/NR)
Row Subtotal	Row Header Overhead+Row Bloom Filter + Row Index	380,435,000
Data File Subtotal	Column Subtotal + Row Subtotal	1,055,780,000
Per Node	Data File Subtotal/Number of Nodes (Includes replication and should be comparable to summation of all SSTABLES on disk for a single node)	1,055,780,000
SSTABLE Index	NR*(10+RKS)	300,000
SSTABLE Bloom Filter	((NR*15)+20)/8	9,378
Base Storage	(Data File Subtotal+SSTABLE Index)+SSTABLE Bloom Filter	1,056,089,378
Additional Replicas	Base Storage*(RF-1)	1,056,089,378
Compaction Overhead	Base Storage*RF	2,112,178,755
Total Storage	(Base Storage+Additional Replicas)+Compaction Overhead	4,224,357,510
Per Node	Total Storage/Number of Nodes	2,112,178,755

Important

The above table is only a sample illustration. For additional guidance specific to your requirements, contact your account representative.

For more information on configuring and deploying Cassandra on Intel Architecture, refer to this document by Intel.