Julie Lermanthedatafarm.com

@julielerman

Performance and Stability Improvements

EF6 Changes for Faster Apps with Fewer Exceptions

In This Module

Faster LINQ Enumerable.Contains Method Compilation Faster Mapping View Generation Using nGen to Reduce JIT Compilation Cost of EF6 Creating Snapshot-Enabled SQL Server Databases Share Open Database Connections Connection Resiliency

Faster Compilation of Enumerable.Containscontext.Ninjas.Where(n=>listOfIds.Contains(n.Id))

EF5 & earlier Expression Tree built with OR statements Building tree suffered with large enumerables Performance issue was in compilation, not DB

EF6 Expression tree built with IN Quick compilation even with large enumerables SQL & DB performance unaffected

Faster Mapping View Generation

Was for big, complex models

Design TimeReduces Startup Cost

Run Time

Contributed byAlireza Haghshenas

Faster Mapping View Generation

Noticable for big, complex models

Contributed by Alireza Haghshenas

Ngen for Faster Startup

No JIT at runtime(~ 1 second) Machine specific

Compile entityframework.dll

natively

ngenInstallentityframework.dll

MSDN doc on Ngenparameters, usage considerations & caveats

juliel.me/ngen_doc

Snapshot Enabled by Default

LiveDatabase

W

R

I

T

E

t

o

D

B

Read-OnlySnapshot

R

E

A

D

f

r

o

m

D

B

Default transaction isolation level is changed to READ_COMMITTED_SNAPSHOTfor databases created using Code First,

potentially allowing for more scalability and fewer deadlocks

SET TRANSACTION ISOLATION LEVEL{ READ UNCOMMITTED| READ COMMITTED| REPEATABLE READ| SNAPSHOT| SERIALIZABLE}

[ ; ]

Open Connections Can Be Re-Used

EntityConnectioncan be instantiated

with an open DbConnection

Connection Resiliency

TransientConnection

Failure

RetryN times

SpecifyMax Retry Period

DbExecutionStrategye.g., SqlAzureExecutionStrategy

Quick Review

Resources

EF Project: EntityFramework.codeplex.com My blog: thedatafarm.com/blog EF Team Blog: blogs.msdn.com/adonet Entity Framework 6 Articles in MSDN Magazine:

EF6 Ninja Edition, Dec 2013 (julieL.me/MSDN_EF6Ninja)Code First Goodies in Entity Framework 6 Jan 2014 (julieL.me/MSDN_EF6CF)

Entity Framework Courses on Pluralsight: julieL.me/PS-Videos LINQ Contains explanation by Diego Vega: julieL.me/EFContains Transient Connection Errors Described: julieL.me/TransientCtx Ngen Documentation: julieL.me/ngen_doc

Julie Lermanthedatafarm.com

@julielerman