Simple-Spring-Memcached http://code.google.com/p/simple-spring-memcached/ A library that enables your code to benefit from distributed caching (via memcached), with minimal configuration and simple annotations.

Bio Nelz Carpentier Sr. Software Engineer at Widgetbox, Inc 10+ Years as a Software Engineer http://www.nelz.net/ http://www.twitter.com/nelz9999 http://www.linkedin.com/in/nelz9999

Nelz Carpentier

Sr. Software Engineer at Widgetbox, Inc

10+ Years as a Software Engineer

http://www.nelz.net/

http://www.twitter.com/nelz9999

http://www.linkedin.com/in/nelz9999

Target Audience Technical Folks Familiar with Spring May be interested in adding Memcached Understand the basics of Caching Understand the basics of Distributed Caching

Technical Folks

Familiar with Spring

May be interested in adding Memcached

Understand the basics of Caching

Understand the basics of Distributed Caching

Target Code / Infrastructure Java Spring Serializable / Externalizable Objects High-Read, Low-Write You control (or can wrap) the methods you want to cache Expensive Read Operations Operational Ability to Support Memcached

Java

Spring

Serializable / Externalizable Objects

High-Read, Low-Write

You control (or can wrap) the methods you want to cache

Expensive Read Operations

Operational Ability to Support Memcached

SSM's Niche

Motivation Broke New Ground? Share My Learnings Self-Evident Concept Not Too Smart Willing to do the work

Broke New Ground?

Share My Learnings

Self-Evident Concept

Not Too Smart

Willing to do the work

Shoulders of Giants Build Maven Cobertura Test TestNG EasyMock Mirror Runtime Spy Memcached Spring / AspectJ Log4J

Build

Maven

Cobertura

Test

TestNG

EasyMock

Mirror

Runtime

Spy Memcached

Spring / AspectJ

Log4J

Desired Characteristics of Caching Needed in many layers Should be transparent to main code flow Similar characteristics Logging Security Cross-cutting concern? AOP to the Rescue!

Needed in many layers

Should be transparent to main code flow

Similar characteristics

Logging

Security

Cross-cutting concern?

AOP to the Rescue!

Configure the ApplicationContext <import resource=&quot;classpath:simplesm-context.xml&quot; /> <bean id=&quot;memcachedConnectionBean&quot; class= &quot;net.nelz.simplesm.config.MemcachedConnectionBean&quot;> <property name=&quot;consistentHashing&quot; value=&quot;true&quot; /> <property name=&quot;nodeList&quot; value=&quot;127.0.0.1:11211 127.0.0.1:11311&quot; /> </bean> <aop:aspectj-autoproxy />

<import resource=&quot;classpath:simplesm-context.xml&quot; />

<bean id=&quot;memcachedConnectionBean&quot; class=

&quot;net.nelz.simplesm.config.MemcachedConnectionBean&quot;>

<property name=&quot;consistentHashing&quot; value=&quot;true&quot; />

<property name=&quot;nodeList&quot; value=&quot;127.0.0.1:11211 127.0.0.1:11311&quot; />

</bean>

<aop:aspectj-autoproxy />

Pseudocode of Read Through Scenario $key = calculateValueCacheName() if cacheHasKey($key), return getFromCache($key) $value = doExpensiveRequestForValue() storeInCache($key, $value) return $value Gets info out of the cache Also back door of putting info into the cache [PS: Pertinent Negative Null]

$key = calculateValueCacheName()

if cacheHasKey($key), return getFromCache($key)

$value = doExpensiveRequestForValue()

storeInCache($key, $value)

return $value

Gets info out of the cache

Also back door of putting info into the cache

[PS: Pertinent Negative Null]

Generating Keys 255 Characters Key + Namespace + Other Characters (~16) No Spaces Default: toString() Preferred: @CacheKeyMethod

255 Characters

Key + Namespace + Other Characters (~16)

No Spaces

Default: toString()

Preferred: @CacheKeyMethod

Why Namespaces? Avoid Collisions Example: Primary Keys Bad: 123 vs 123 Good: Vet:123 vs Pet:123

Avoid Collisions

Example:

Primary Keys

Bad: 123 vs 123

Good: Vet:123 vs Pet:123

RTA - Example @ReadThroughAssignCache( assignedKey = &quot;InTheWindow&quot;, namespace = &quot;DOG&quot;, expiration = 300) Dog getDogInWindow() { ... }

@ReadThroughAssignCache(

assignedKey = &quot;InTheWindow&quot;,

namespace = &quot;DOG&quot;,

expiration = 300)

Dog getDogInWindow() {

...

}

RTS – Example 1 @ReadThroughSingleCache( keyIndex = 0, namespace = &quot;VETS&quot;, expiration = 300) Vet getVet(Long id) { ... }

@ReadThroughSingleCache(

keyIndex = 0,

namespace = &quot;VETS&quot;,

expiration = 300)

Vet getVet(Long id) {

...

}

RTS – Example 2 @ReadThroughSingleCache( keyIndex = 1, namespace = &quot;VETS&quot;, expiration = 300) Vet getVet(Credentials cred, Long id) { ... }

@ReadThroughSingleCache(

keyIndex = 1,

namespace = &quot;VETS&quot;,

expiration = 300)

Vet getVet(Credentials cred, Long id) {

...

}

Cardinality Options 1-to-1, 1-to-Many, Invariant “ KEY” -> Y “ KEY” -> List<Value> @ReadThroughAssignCache 1-to-1, 1-to-Many, Parameterized Key -> Value Key -> List<Value> @ReadThroughSingleCache Many-to-Many List<Key> -> List<Value> @ReadThroughMultiCache

1-to-1, 1-to-Many, Invariant

“ KEY” -> Y

“ KEY” -> List<Value>

@ReadThroughAssignCache

1-to-1, 1-to-Many, Parameterized

Key -> Value

Key -> List<Value>

@ReadThroughSingleCache

Many-to-Many

List<Key> -> List<Value>

@ReadThroughMultiCache

List -> List Contract Requires: Agree in Length Agree in Sequence Each Key/Value Pair is an individual cache entry No Map support (yet?) Subset Pass-Through

Requires:

Agree in Length

Agree in Sequence

Each Key/Value Pair is an individual cache entry

No Map support (yet?)

Subset Pass-Through

RTM - Example @ReadThroughMultiCache( keyIndex = 0, namespace = &quot;VETS&quot;, expiration = 300) List<Vet> getVet(List<Long> ids) { ... }

@ReadThroughMultiCache(

keyIndex = 0,

namespace = &quot;VETS&quot;,

expiration = 300)

List<Vet> getVet(List<Long> ids) {

...

}

Pseudocode of Invalidate Scenario $key = calculateValueCacheName() doUnderlyingOperations() deleteFromCache($key) Removes info from the cache

$key = calculateValueCacheName()

doUnderlyingOperations()

deleteFromCache($key)

Removes info from the cache

IAC – Example @InvalidateAssignCache( assignedKey = &quot;InTheWindow&quot;, namespace = &quot;DOG&quot;) void removeFromWindow(Dog dog) { ... }

@InvalidateAssignCache(

assignedKey = &quot;InTheWindow&quot;,

namespace = &quot;DOG&quot;)

void removeFromWindow(Dog dog) {

...

}

ISC – Example @InvalidateSingleCache( keyIndex = 0, namespace = &quot;FISH&quot;) void died(Fish fish) { ... }

@InvalidateSingleCache(

keyIndex = 0,

namespace = &quot;FISH&quot;)

void died(Fish fish) {

...

}

IMC – Example @InvalidateMultiCache( keyIndex = 1, namespace = &quot;DOG&quot;) void sellLitter(Buyer to, List<Dog> dogs) { ... }

@InvalidateMultiCache(

keyIndex = 1,

namespace = &quot;DOG&quot;)

void sellLitter(Buyer to, List<Dog> dogs) {

...

}

Pseudocode for Update Scenario doUnderlyingOperations() $key = calculateValueCacheName() $value = harnessValueToStore() storeInCache($key, $value) Puts info into the cache

doUnderlyingOperations()

$key = calculateValueCacheName()

$value = harnessValueToStore()

storeInCache($key, $value)

Puts info into the cache

UAC - Example @UpdateAssignCache( assignedKey = &quot;InTheWindow&quot;, dataIndex = -1, namespace = &quot;DOG&quot;, expiration = 300) Dog chooseDogForWindow() { ... }

@UpdateAssignCache(

assignedKey = &quot;InTheWindow&quot;,

dataIndex = -1,

namespace = &quot;DOG&quot;,

expiration = 300)

Dog chooseDogForWindow() {

...

}

USC - Example @UpdateSingleCache( keyIndex = 0, dataIndex = 0, namespace = &quot;FISH&quot;, expiration = 300) void addToInventory(Fish fish) { ... }

@UpdateSingleCache(

keyIndex = 0,

dataIndex = 0,

namespace = &quot;FISH&quot;,

expiration = 300)

void addToInventory(Fish fish) {

...

}

UMC - Example @UpdateMultiCache( keyIndex = 2, dataIndex = -1, namespace = &quot;DOG&quot;, expiration = 300) List<Dog> newLitter(Dog mom, Dog dad, List<Long> ids) { ... }

@UpdateMultiCache(

keyIndex = 2,

dataIndex = -1,

namespace = &quot;DOG&quot;,

expiration = 300)

List<Dog> newLitter(Dog mom, Dog dad, List<Long> ids) {

...

}

DEMO DEMO... Demo... Demo... Demo.

DEMO...

Demo...

Demo...

Demo.

Protection from Exceptions Exceptions from (your) underlying code should flow as normal Exceptions within the caching code should be invisible to user, other than via log Commons-logging / Log4J

Exceptions from (your) underlying code should flow as normal

Exceptions within the caching code should be invisible to user, other than via log

Commons-logging / Log4J

Best Practices Externalizable (!!!) Up to 8x faster!?! Single Canonical Representation How to do aggregate collections Invalidates on Delete Updates on Save

Externalizable (!!!)

Up to 8x faster!?!

Single Canonical Representation

How to do aggregate collections

Invalidates on Delete

Updates on Save

What SSM Doesn't Do Stampede Protection or Soft Locks Namespace Invalidation Multi-Invalidation / Method Multi-Parameter Keys

Stampede Protection or Soft Locks

Namespace Invalidation

Multi-Invalidation / Method

Multi-Parameter Keys

Possible Future Features Multiple Logical Memcacheds Cache Observers Second-level cache

Multiple Logical Memcacheds

Cache Observers

Second-level cache

Version 2.0 Changes Package Structure Remove Index Params, Adopt Annotations -1 -> @ReturnValueKeyProvider 0+ -> @ParameterValueKeyProvider Key Calculation Spring Bean Nameable @ReturnValueKeyProvider( keyProviderBeanName = “myBeanName” )

Package Structure

Remove Index Params, Adopt Annotations

-1 -> @ReturnValueKeyProvider

0+ -> @ParameterValueKeyProvider

Key Calculation

Spring Bean Nameable

@ReturnValueKeyProvider(

keyProviderBeanName = “myBeanName”

)

Other Projects to Know About Statsproxy - Monitoring Supported by Gear6 Brutis - Benchmarking Also by Gear6 Xmemcached Young Whalin Old, Stable Not Maintained?

Statsproxy - Monitoring

Supported by Gear6

Brutis - Benchmarking

Also by Gear6

Xmemcached

Young

Whalin

Old, Stable

Not Maintained?

Presentation and Demo Files Blog Post: http://nelz.net/2009/10/02/ssm-at-svcc/ On Project Page: http://code.google.com/p/simple-spring-memcached/ Presentation Demo Code Also on SlideShare Gliffy.com

Blog Post: http://nelz.net/2009/10/02/ssm-at-svcc/

On Project Page:

http://code.google.com/p/simple-spring-memcached/

Presentation

Demo Code

Also on SlideShare

Gliffy.com

Photo Credits http://www.flickr.com/photos/adulau/3086751588/ http://www.flickr.com/photos/edrabbit/3440426582/ http://www.flickr.com/photos/nielsvk/258851215/ http://www.flickr.com/photos/origomi/22442743/ http://www.flickr.com/photos/samcrockett/2213593924/ http://www.flickr.com/photos/themarkpike/83868756/ http://www.flickr.com/photos/bohman/210977249/ http://www.flickr.com/photos/red5standingby/235794106/ http://www.flickr.com/photos/roblee/375671072/ http://www.flickr.com/photos/andyandorla/239043213/ http://www.flickr.com/photos/chrisdag/1225937650/ http://www.flickr.com/photos/mechanikat/2727944748/ http://www.flickr.com/photos/expressmonorail/3694867130/ http://www.flickr.com/photos/ttstam/3833225072/ http://www.flickr.com/photos/vernhart/1574355240/

http://www.flickr.com/photos/adulau/3086751588/

http://www.flickr.com/photos/edrabbit/3440426582/

http://www.flickr.com/photos/nielsvk/258851215/

http://www.flickr.com/photos/origomi/22442743/

http://www.flickr.com/photos/samcrockett/2213593924/

http://www.flickr.com/photos/themarkpike/83868756/

http://www.flickr.com/photos/bohman/210977249/

http://www.flickr.com/photos/red5standingby/235794106/

http://www.flickr.com/photos/roblee/375671072/

http://www.flickr.com/photos/andyandorla/239043213/

http://www.flickr.com/photos/chrisdag/1225937650/

http://www.flickr.com/photos/mechanikat/2727944748/

http://www.flickr.com/photos/expressmonorail/3694867130/

http://www.flickr.com/photos/ttstam/3833225072/

http://www.flickr.com/photos/vernhart/1574355240/

Questions Questions?