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Measurements of Version 3.0 (Beta) RELAP5-3DRELAP5-3D International Users Seminar 2010

[insert optional photo(s) here]

Sep 20-23, 2010

Outline

• Static Measures• Improvements to the 3D capability in RELAP5-3D• Dynamic Measures

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Static and Dynamic Measures• Dynamic Measures

– Metrics that are obtained when the code is run– Coverage analysis, profiling, run speed, etc

• Static measures– Metrics that apply to the code when it is not running– Code structure, features, user problems, etc.

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Feature Comparison 2.4 and Beta (3.0)

Category Version 2.4.3 (Pre-F95) Beta (Post-F95)Direct Access Restart-Plot File

Available Eliminated

Pre-run GUI RGUI Launch Station, SNAP

RGUI Limited Launch Station, SNAP

Runtime GUI RGUI Plant Image Not converted

RGUI Replay Available Eliminated

SCDAP Available Not converted

Compilers Many, but older, compilers Only Intel 9.1, 10.1

•Downgrades

•Upgrades

* These are reported in another presentation

Feature Comparison 2.4 and Beta (3.0)

Category Version 2.4.1.2 (Pre-F95) Beta (Post-F95)Database Linear, index-pointers F95 Modules, derived types

Memory Upper-limited Expands to fit user’s model

Coding Extended F66, F77, F90 and compiler extensions

F95

Modularity Unstructured Structured (strongly modular)

Dead Code Many unused subroutines 162 unused files removed

Feature Comparison 2.4 and Beta (3.0)

Category Version 2.4.1.2 (Pre-F95) Beta (Post-F95)Platforms Windows, Unix Linux, Windows, Unix

Restart-file form Combined restart-plot file Separate restart and plot files

Portability O/S specific bit-, time-, and location-intrinsics

Fully portable F95 intrinsic library

Ordinary Binarymachine dependent rstplt

XDR binary machine independent files

Fluids Base 2.4.1.2 Base + additions*

Physical models Base 2.4.1.2 Base + additions*

•Upgrades

Spaghetti Code to Structured Code• Spaghetti Code is code that is hard to read because

– Tangled (interwoven) logic paths. Symptom: go-to’s and line labels– Knots (backward jumps). Symptom: backward go to.– Obscure coding (multiple-return, assign-stmt, computed go to, etc.)– Lacks consistent indentation and other helpful programming style

• Spaghetti code is considered bad practice – Prone to experience errors, – Cause of errors are difficult to locate

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Improvement: Restructured Code• Computer Science solution – Apply structured programming• Commercial restructuring package applied (between 2.4 and 3.0)

– Workaround for pre-compiler directives was created• Restructurer actions

– Eliminate go-to statements– Pull sections of code together– Enforce consistent style– Eliminate dead code w/in subroutines

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05-GA

Static Measure: Readability measures

Go to statements 2.4 % Beta % 2.4/Beta

File w/ 0 GO TOs 255 46 420 67 0.66File w/ 10+ GO TOs 132 24 65 10 2.03File w/ 51+ GO TOs 41 7.4 4 .63 10.25File w/ 86+ GO TOs 14 2.5 1 .16 14.00Total GO TOs 6707 3 2209 .79 3.04Computed GO TOs 100 .04 7 .003 14.29Backward GO TOs ** Spaghetti **

822 .3 45 .016 18.27

• Reduction of GOTO statements• Lines of code: 249400 (2.4.1.2), 278100 (3.0.0)• Source code files: 554 (2.4.1.2), 630 (3.0.0)

05-GA

Static Measure: Line Label Reduction

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0 labels 100 ormorelabels

Totallabels

Labelsof

formats

Non-formatlabels

Reduction in Labels

Af terBefore

Static Measure (Spaghetti) – McCabe Index

Complexity 2.4.1.2 BetaMaximum cyclomatic number 982 460Files with cyclomatic number >= 100 68 13

• McCabe Cyclomatic index = industry-standard, code-complexity measure.

• Number of independent linear paths through code• Indicates the number of branches within it. • Higher indices => more branches => harder to maintain.

• Cyclomatic index of 100 or less is generally considered low complexity and good programming

• Only input processing subroutines have 100+ index

Static Measures: Nesting and Documentation

Measurement Category 2.4.1.2 BetaMaximum Nesting (levels deep) 20 15 Best comments to code ratio 6.64 32.2Files w/ comments to code ratio >= 0.3 390 954

• Nesting is containment of one programming structure (loop, select, or sequence) within another

• Nesting level is the number of such structures containing a block of code• Less nesting is generally easier read and maintain

• Internal documentation (comments) improves readability• Documentation was added. Guidelines were applied.

Static Measure: User Problems Solved

Year Reports ResolvedFixed after

2.4.1.2Conversion to

F95 fixed it1998 85 31 1 11999 75 50 1 12000 92 47 2 22001 86 67 3 32002 86 72 0 02003 61 44 2 22004 62 39 7 72005 55 32 30 22006 71 36 35 12007 51 27 23 42008 47 23 18 52009 42 10 10 0Total 813 478 132 28

Dynamic Measure: Coverage Analysis

CategoryPre-F95

Version 2.4.1.2F95

Beta VersionTest Cases 188 3130Product Release 188 221PVM Dt Tests 0 2856DA 0 53

Coverage Analysis Files Stmts Files StmtsRelap Directory 63.87 44.72 80.37 61.51Envrl Directory 35.46 38.91 54.24 51.91

• Beta code is much more heavily tested• Beta code’s test suite covers a much higher percentage of files and

statements– Reduces the likelihood of error

Improvements to 3D Capability of RELAP5-3D• Viscosity terms for Cartesian and Cylindrical Coordinates, SI

– Beta Version 3.0.0: Liquid momentum equations, 2009– Version 3.0.1: Gas momentum equations, 2010– Version 3.0.1: Simple turbulence term, 2010

• Would like more grid cells for good turbulence modeling• Want more 3D volumes for many modeling purposes• Version 2.4 had many 3D restrictions

– Could receive message:“Too many parallel connections”• E.G. Code stops with that message on a 6x6x6 region.

– 2400 junctions upper limit– 999 volumes upper limit

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Improvements to 3D of RELAP5-3D (cont.)• Eliminated 3D Limits in Beta and post-Beta

– Beta Version 3.0.0: “Parallel connections” overcome by allocation– Version 3.0.1: 2400 junction limit overcome by allocating– Version 3.0.1: 999 (artificial) volume limit removed

• Up to 9x99x99 volumes possible • Enough for many modeling needs

• Version 2.4 solvers too limited for these large regions– Ver. 2.4 Original default solver, MA-18, too slow– PGMRES is faster but had its own hard-coded size limits– Ver. 2.4 default solver, BPLU, limited by size of FA array

• Version 3.0.0 removes hard-coded and FA size restrictions

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Dynamic Measure: R5-3D Times on 3D-Region SI• Cylindrical 3D region from Loft L2-5 Test• 100 Advancements with Semi Implicit Method

– Full multi-D (cross derivative terms included)• Whole code transient CPU time with solvers PGMRES

and BPLU• Platform: Sun AMD Opteron, Open Suse 11.2, ifort 10.1

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MA18 Times8x8x5 2233.78x8x8 17529.8x8x10 47527.8x8x13 85430.Too slow!

0 500 1000 1500 2000 2500 3000 3500 400005

101520253035404550

Semi-Implicit, 6x6xN

BPLU

PGMRES

N = 6, 12, 24,48, 96

0 500 1000 1500 2000 2500 3000 3500 4000 45000

10

20

30

40

50

60

Semi-Implicit, 8x8xN BPLU

PGMRES

Dynamic Measure: R5-3D 3D-Regions Times - NI

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0 2000 4000 6000 8000 10000 120000

5000

10000

15000

20000

R5-3D 8x8xN NearlyBPLU

PGMRES

Number of Variables

N = 5, 8, 13, 16, 32, 64

010

0020

0030

0040

0050

0060

0070

0080

0090

0010

000

0100020003000400050006000700080009000

R5-3D Nearly Runtime

BPLU

PGMRES

CPU

Tim

e (s

ec)

6x6xN region, N=6, 12, 24, 48, 96

Number of variables

1000 10000100

1000

10000

100000

Log-Log R5-3D NearlyBPLUPGMRESLinearO(n^2)

CPU

Tim

e (s

ec)

Number of variables

8x8xN region, N=5, 8, 13, 16, 32, 64

100 1000 1000010

100

1000

10000

Log-Log R5-3D NearlyBPLUPGMRESLinearO(n**2)

6x6xN region, N=6, 12, 24, 48, 96

Dynamic Measures: Grind time• Grind time is average time taken for one advancement.

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BPLU PGMRESSemi Nearly Semi Nearly

6x6x6 0.0198s 0.199s 0.0221s 0.190s

6x6x24 0.054s 0.82s 0.064s 3.77s

6x6x96 0.363s 3.64s 0.437s 76.82s

8x8x8 0.033s 2.44s 0.0387s 1.46s

8x8x16 0.072s 5.96s 0.11s 7.97s

8x8x64 0.47s 26.4s 0.56s 161.s

• Non-solver RELAP5-3D operations could obscure the solver times.

Dynamic Measure: R5-3D Solver Clock Cycles NI• BPLU time is O(n), PGMRES time is O(n2) as n increases.

20100 1000 10000

1.0E+4

1.0E+5

1.0E+6

1.0E+7

1.0E+8

1.0E+9

1.0E+10

Log-Log Solver 6x6xN NI BPLUPGMRESLinearQuadratic

1000 10000100000000

1000000000

10000000000

100000000000

Log-Log Solver 8x8xN NI BPLU

PGMRES

Linear

O(n^2)

0 2000 4000 6000 8000 10000 120000

10000000002000000000300000000040000000005000000000600000000070000000008000000000

Solver 6x6xN NI Cycles

BPLU

PGMRES

0 2000 4000 6000 8000 10000 12000 140000

2000000000400000000060000000008000000000

1000000000012000000000140000000001600000000018000000000

Solver 8x8xN NI CyclesBPLU

PGMRES

ConclusionsUpside of Beta version vs. version 2.4• Beta version 3.0 has many new features.• Beta version expands memory to fit user’s model.• Beta version has virtually no spaghetti coding• Beta version of RELAP5-3D has much improved 3D capability• Beta version has very efficient solvers for 3D regions

Downside• RGUI mostly unavailable• Support fewer compilers

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