Most ASP.NET applications that needs scalability are data intensive and use relational database as their data store. This presentation provides information about relational data, object relational mapping, its management, caching strategies and handling collections in a distributed cache.

1. Alachisoft
.NET Performance Solutions
How to Handle Relational Data
in a Distributed Cache
Iqbal Khan
iqbal@alachisoft.com Ph: +1 (925) 236-2125
www.alachisoft.com
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2. Alachisoft
Following Applications Need Scalability
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ASP.NET Apps
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WCF & .NET Web Services
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To quickly process very large amounts of data thru distribution
Grid Computing Apps
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To handle millions of requests
Big Data Apps
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To handle millions of users
To process very large computations thru distribution
Other .NET Server Apps
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NCache
To handle millions of requests
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3. Alachisoft
Data Storage is Scalability Bottleneck
ASP.NET/WCF Example
App Database
ASP.NET/WCF Servers
Database Servers
Data Access
Scale Web Farm
Web Clients
Http Calls
...
NCache
Load Balancer
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ASP.NET Session
Storage
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4. Alachisoft
The Solution
Scalable In-Memory Distributed Cache
NCache
NCache
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5. Alachisoft
What is an In-Memory Distributed Cache?
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Cluster of multiple inexpensive cache servers
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Synchronizes cache updates across all cache servers
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Cache updates are immediately visible from all cache servers
Linearly scales transaction & memory capacity
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Pools their memory and CPU into one logical capacity
Just add more cache servers to grow capacity
Replicates data for reliability
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NCache
Intelligent replication without compromising performance & scalability
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6. Alachisoft
NCache: In-Memory Distributed Cache
ASP.NET Web Apps
WCF Web Services
Grid Computing Apps
(.NET)
.NET Server Apps
Distributed Cache Cluster
Memory pooled from all cache servers
Scale Horizontally
Windows 2008/2012 (64-bit)
Filesystem
NCache
Database Servers
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Mainframe
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7. Alachisoft
What Data to Cache?
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Reference Data
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Transactional Data
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Does not change very frequently (but is not static)
Changes frequently (as frequently as in a few seconds)
Most Cached Data is Relational
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NCache
Comes from relational databases
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8. Alachisoft
Challenge: Cache versus Relational Data
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Cache provides a Hashtable-like interface
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Each item is separate and has a “key” and a “value”.
“Value” is usually an “object”
Relational data has relationships between entities
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NCache
This is a challenge for your application
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9. Alachisoft
Peek into Caching API
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Read from the Cache
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Add to the Cache
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object obj = cache.Get(“myKey”);
object obj = cache[“myKey”];
bool isPresent = cache.Contains(“myKey”);
cache.Add(“myKey”, obj);
cache.Insert(“myKey”, obj);
cache[“myKey”] = obj;
Remove from the Cache
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NCache
object obj = cache.Remove(“myKey”);
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10. Alachisoft
First Step: Use CacheDependency
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Lets you manage relationships in the cache
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One cached item depends on another
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A depends on B and B depends on C. Change in C triggers both A & B
Feature introduced by ASP.NET Cache
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If target cached item updated/removed, dependent automatically removed
Cascaded dependencies possible
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Cache keeps track of a one-way “dependency” between cached items
Key based dependency is our focus here
NCache also provides it
NCache
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11. Alachisoft
Second Step: Use Object Relational Mapping
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Benefits of O/R Mapping
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Benefits of O/R Mapping Tools
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Cut down development time
Improve code quality in persistence & domain objects
Simplifies programming. No need to directly use ADO.NET
Which O/R Mapping Tools to Use?
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Simplifies programming by mapping domain objects to data model
Promotes code reuse of persistence and domain objects
Entity Framework (Microsoft)
NHibernate (Open Source)
At Least Map Domain Objects to Database
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NCache
Map to database entities
Capture relationships in these objects
Transform DataReader or DataTable into domain objects
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12. Alachisoft
Mapping Domain Objects to Database
Data Model
NCache
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13. Alachisoft
What is a Primary Object?
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It is a domain object
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Starting point for the application
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Mapped to a table in the database
Application fetches this objects first
All other objects fetched in relation to this object
All other objects fetched in relation to this object
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NCache
One-to-many and many-to-one relationships
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14. Alachisoft
Mapping Domain Objects to Database
NCache
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15. Alachisoft
1-1/n-1 Relationships in Distributed Cache
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Strategy 1: cache related object with primary object
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Strategy 2: cache related object separately
NCache
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16. Alachisoft
1-1/n-1 Relationships in Distributed Cache
Cache related object with primary object
NCache
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17. Alachisoft
1-1/n-1 Relationships in Distributed Cache
Cache related object separately
NCache
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18. Alachisoft
1-n Relationships in Distributed Cache
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Strategy 1: cache related objects collection with primary object
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Strategy 2: cache related objects separately separately
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Cache entire collection as part of the primary object
Cache entire collection as one item but separately
Strategy 3: cache related objects from collections separately
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NCache
Cache each item of the collection separately
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19. Alachisoft
1-n Relationships in Distributed Cache
Cache related object collection separately
NCache
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20. Alachisoft
1-n Relationships in Distributed Cache
Cache each object in related collection separately
NCache
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21. Alachisoft
m-n Relationships in Distributed Cache
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Many-to-many relationships don’t exist in domain objects
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Instead, represented by two one-to-many relationships
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E.g. Customer->Orders and Product->Orders
Intermediary object contains many-to-one references
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NCache
E.g. Order has a reference to Customer and Product
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22. Alachisoft
Handling Collections in Distributed Cache
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Scenario 1: cache entire collection as one item
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Scenario 2: cache each collection item separately
NCache
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23. Alachisoft
Handling Collections in Distributed Cache
Cache entire collection as one item
NCache
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24. Alachisoft
Handling Collections in Distributed Cache
Cache each collection item separately
NCache
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25. Alachisoft
Hands on Demo
NCache
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Some Object Caching Features
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Expirations
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Locking (Pessimistic & Optimistic)
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Lock/Unlock for pessimistic locking (writer-lock)
Object versioning for optimistic locking (reader-lock)
Bulk Operations
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Absolute-time + idle-time
Auto-reload data on expiration (if read-thru enabled)
Bulk Get, Add, Insert, and Remove
Async Operations
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NCache
Async Add, Insert, and Remove
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27. Alachisoft
Synchronize Cache with Data Sources
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Synchronize with Relational Databases (SQL, Oracle, etc.)
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SqlDependency
OracleDependency
DbDependency
Synchronize with non-Relational Data Sources
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NCache
File based Cache Dependency
Custom Cache Dependency
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28. Alachisoft
Data Grouping in the Cache
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Group/Subgroup
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Tags
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Named Tags
NCache
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29. Alachisoft
Searching the Cache
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Parallel Queries with Object Query Language (OQL)
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Parallel LINQ Queries
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SQL-like query language to search cache based on object attributes
Standard LINQ queries can search the cache
Indexing Object Attributes for Querying
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NCache
Create indexes on object attributes to speed up queries
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30. Alachisoft
Some Other Features
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NHibernate L2 Cache Provider
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Entity Framework L2 Cache
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Plug into NHibernate application without any code change
Plug into Entity Framework application without any code change
Dynamic Compact Serialization
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NCache
Faster and more compact then regular .NET serialization
No code writing required
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31. Alachisoft
What to Do Next?
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Find more about NCache
Download 60-day Trial
Request a Personalized LIVE Demo
Read product Documentation
Thank You
NCache 4.1
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