POWERSHELL
OPTIMIZATION FOR SPEED
Tim Curwick
Kirk Munro
MadWithPowerShell.com
@poshoholic
[email protected]
Director of Learning Solutions
DevOps, Azure, Automation
Consultant at RBA, Inc.
Learn on Demand Systems
Tim
Curwick
@MadWPowerShell
Microsoft
Computer
My
PowerShell MVP
nerd for 35 years
favorite food is cows
Kirk
Munro
@Poshoholic
10-time
~20
PowerShell MVP
years building IT solutions
Organic,
paleo, healthy
BALANCE
BALANCE
Minimize
speed
what needs to be optimized for
PRECOMPILING VS JIT COMPILING
PRECOMPILING VS JIT COMPILING
TESTING
Test
Test
again
Test
again
PROFILES
Don’t
use profiles
MODULES
Avoid
modules
FUNCTIONS
Code
in a function is faster
FUNCTIONS
Code
in a function is faster
Using
more than one function is slower
NATIVE CLASS DEFINITION
Code
in a class definition is faster
.NET METHODS
.Net
methods are fast
PIPELINES
Don’t
use pipelines
LOOPS
LOOPS
Loop
Pipe to ForEach-Object
Pipe to Measure-Object
.ForEach() method
For loop
ForEach loop
Relative time taken
14.2
7.0
4.8
2.3
1.0
LOOPS
Loop
Pipe to ForEach-Object
Pipe to Measure-Object
.ForEach() method
For loop
ForEach loop
Relative time taken
PS 5.0
PS 5.1
14.2
7.0
4.8
2.3
1.0
38.0
1.7
35.7
2.1
0.9
LOOPS
Loop
Pipe to ForEach-Object
Pipe to Measure-Object
.ForEach() method
For loop
ForEach loop
Relative time taken
PS 5.0
PS 5.1
5.1+log
14.2
7.0
4.8
2.3
1.0
38.0
1.7
35.7
2.1
0.9
56.5
6.8
43.0
2.0
0.9
BREAK/CONTINUE
NORMALIZE CALCULATIONS
Do
not repeat anything that does not
need to be repeated
SIMPLIFY CALCULATIONS
SIMPLIFY CALCULATIONS
3x3=?
SIMPLIFY CALCULATIONS
3x3=?
3.14159265 = ?
SIMPLIFY CALCULATIONS
Avoid
floating point operations
Avoid
more complex operations
AVOID UNUSED CODE
AVOID UNUSED CODE
Avoid
comments
Avoid
Write-Debug, Write-Verbose,
Write-Error
Avoid
unnecessary tests