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[ 4 / 4 ] Application profile is long enough (13.57 s)
To have good quality measurements, it is advised that the application profiling time is greater than 10 seconds.
[ 0 / 3 ] Optimization level option not used
To have better performances, it is advised to help the compiler by using a proper optimization level (-O2 of higher). Warning, depending on compilers, faster optimization levels can decrease numeric accuracy.
[ 0 / 3 ] Helper debug compilation options -g and -fno-omit-frame-pointer are missing
-g option gives access to debugging informations, such are source locations and -fno-omit-frame-pointer improve the accuracy of callchains found during the application profiling.
[ 0 / 3 ] Architecture specific options are not used
Architecture specific options are needed to produce efficient code for a specific processor ( -x(target) or -ax(target) ).
[ 2 / 2 ] Application is correctly profiled ("Others" category represents 0 % of the execution time)
To have a representative profiling, it is advised that the category "Others" represents less than 20% of the execution time in order to analyze as much as possible of the user code
[ 4 / 4 ] Enough time of the experiment time spent in analyzed loops (57.89%)
If the time spent in analyzed loops is less than 30%, standard loop optimizations will have a limited impact on application performances.
[ 4 / 4 ] Loop profile is not flat
At least one loop coverage is greater than 4% (16.84%), representing an hotspot for the application
[ 4 / 4 ] Enough time of the experiment time spent in analyzed innermost loops (48.31%)
If the time spent in analyzed innermost loops is less than 15%, standard innermost loop optimizations such as vectorisation will have a limited impact on application performances.
[ 3 / 3 ] Less than 10% (0%) is spend in BLAS1 operations
It could be more efficient to inline by hand BLAS1 operations
[ 3 / 3 ] Cumulative Outermost/In between loops coverage (9.58%) lower than cumulative innermost loop coverage (48.31%)
Having cumulative Outermost/In between loops coverage greater than cumulative innermost loop coverage will make loop optimization more complex
[ 2 / 2 ] Less than 10% (0%) is spend in Libm/SVML (special functions)
[ 2 / 2 ] Less than 10% (0%) is spend in BLAS2 operations
BLAS2 calls usually could make a poor cache usage and could benefit from inlining.
| Loop ID | Module | Analysis | Penalty Score | Coverage (%) | Vectorization Ratio (%) | Vector Length Use (%) |
|---|---|---|---|---|---|---|
| ►987 | libgromacs_mpi.so.7.0.0 | Inefficient vectorization. | 285 | 16.84 | 100 | 94.93 |
| ○ | [SA] Presence of expensive FP instructions - Perform hoisting, change algorithm, use SVML or proper numerical library or perform value profiling (count the number of distinct input values). There are 64 issues (= instructions) costing 4 points each. | 256 | ||||
| ○ | [SA] Inefficient vectorization: more than 10% of the vector loads instructions are unaligned - When allocating arrays, don’t forget to align them. There are 7 issues ( = arrays) costing 2 points each | 14 | ||||
| ○ | [SA] Presence of special instructions executing on a single port (SHUFFLE/PERM, BROADCAST) - Simplify data access and try to get stride 1 access. There are 9 issues (= instructions) costing 1 point each. | 9 | ||||
| ○ | [SA] More than 20% of the loads are accessing the stack - Perform loop splitting to decrease pressure on registers. This issue costs 2 points. | 2 | ||||
| ○ | [SA] Inefficient vectorization: use of shorter than available vector length - Force compiler to use proper vector length. CAUTION: use of 512 bits vectors could be more expensive than 256 bits on some processors. Use intrinsics (costly and not portable). The issue costs 2 points. | 2 | ||||
| ○ | [SA] Inefficient vectorization: use of masked instructions - Simplify control structure. The issue costs 2 points. | 2 | ||||
| ○ | Warning! There is no dynamic data for this loop. Some checks can not been performed. | 0 | ||||
| ►985 | libgromacs_mpi.so.7.0.0 | Inefficient vectorization. | 285 | 6.26 | 100 | 95.28 |
| ○ | [SA] Presence of expensive FP instructions - Perform hoisting, change algorithm, use SVML or proper numerical library or perform value profiling (count the number of distinct input values). There are 64 issues (= instructions) costing 4 points each. | 256 | ||||
| ○ | [SA] Inefficient vectorization: more than 10% of the vector loads instructions are unaligned - When allocating arrays, don’t forget to align them. There are 7 issues ( = arrays) costing 2 points each | 14 | ||||
| ○ | [SA] Presence of special instructions executing on a single port (SHUFFLE/PERM, BROADCAST) - Simplify data access and try to get stride 1 access. There are 9 issues (= instructions) costing 1 point each. | 9 | ||||
| ○ | [SA] More than 20% of the loads are accessing the stack - Perform loop splitting to decrease pressure on registers. This issue costs 2 points. | 2 | ||||
| ○ | [SA] Inefficient vectorization: use of shorter than available vector length - Force compiler to use proper vector length. CAUTION: use of 512 bits vectors could be more expensive than 256 bits on some processors. Use intrinsics (costly and not portable). The issue costs 2 points. | 2 | ||||
| ○ | [SA] Inefficient vectorization: use of masked instructions - Simplify control structure. The issue costs 2 points. | 2 | ||||
| ○ | Warning! There is no dynamic data for this loop. Some checks can not been performed. | 0 | ||||
| ►21809 | libgromacs_mpi.so.7.0.0 | Partial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access. | 6 | 3.66 | 0 | 12.5 |
| ○ | [SA] Presence of constant non unit stride data access - Use array restructuring, perform loop interchange or use gather instructions to lower a bit the cost. There are 3 issues ( = data accesses) costing 2 point each. | 6 | ||||
| ►994 | libgromacs_mpi.so.7.0.0 | Inefficient vectorization. | 413 | 2.47 | 100 | 96.67 |
| ○ | [SA] Presence of expensive FP instructions - Perform hoisting, change algorithm, use SVML or proper numerical library or perform value profiling (count the number of distinct input values). There are 96 issues (= instructions) costing 4 points each. | 384 | ||||
| ○ | [SA] Inefficient vectorization: more than 10% of the vector loads instructions are unaligned - When allocating arrays, don’t forget to align them. There are 7 issues ( = arrays) costing 2 points each | 14 | ||||
| ○ | [SA] Presence of special instructions executing on a single port (SHUFFLE/PERM, BROADCAST) - Simplify data access and try to get stride 1 access. There are 9 issues (= instructions) costing 1 point each. | 9 | ||||
| ○ | [SA] More than 20% of the loads are accessing the stack - Perform loop splitting to decrease pressure on registers. This issue costs 2 points. | 2 | ||||
| ○ | [SA] Inefficient vectorization: use of shorter than available vector length - Force compiler to use proper vector length. CAUTION: use of 512 bits vectors could be more expensive than 256 bits on some processors. Use intrinsics (costly and not portable). The issue costs 2 points. | 2 | ||||
| ○ | [SA] Inefficient vectorization: use of masked instructions - Simplify control structure. The issue costs 2 points. | 2 | ||||
| ○ | Warning! There is no dynamic data for this loop. Some checks can not been performed. | 0 | ||||
| ►21402 | libgromacs_mpi.so.7.0.0 | Partial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access. | 1002 | 1.82 | 54.1 | 40.16 |
| ○ | [SA] Too many paths (2514 paths) - Simplify control structure. There are 2514 issues ( = paths) costing 1 point, limited to 1000. | 1000 | ||||
| ○ | [SA] Non innermost loop (Outermost) - Collapse loop with innermost ones. This issue costs 2 points. | 2 | ||||
| ○ | Warning! Some static analysis are missing because the loop has too many paths. Use a higher value for --maximal_path_number option. | 0 | ||||
| ○2124 | libgromacs_mpi.so.7.0.0 | Partial or unexisting vectorization - No issue detected | 0 | 1.68 | 0 | 6.25 |
| ►21401 | libgromacs_mpi.so.7.0.0 | Partial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access. | 9 | 1.67 | 91.67 | 85.94 |
| ○ | [SA] Presence of expensive instructions (GATHER/SCATTER) - Use array restructuring. There are 1 issues (= instructions) costing 4 points each. | 4 | ||||
| ○ | [SA] Inefficient vectorization: use of shorter than available vector length - Force compiler to use proper vector length. CAUTION: use of 512 bits vectors could be more expensive than 256 bits on some processors. Use intrinsics (costly and not portable). The issue costs 2 points. | 2 | ||||
| ○ | [SA] Presence of constant non unit stride data access - Use array restructuring, perform loop interchange or use gather instructions to lower a bit the cost. There are 1 issues ( = data accesses) costing 2 point each. | 2 | ||||
| ○ | [SA] Presence of special instructions executing on a single port (BROADCAST) - Simplify data access and try to get stride 1 access. There are 1 issues (= instructions) costing 1 point each. | 1 | ||||
| ○ | Warning! There is no dynamic data for this loop. Some checks can not been performed. | 0 | ||||
| ○21742 | libgromacs_mpi.so.7.0.0 | Partial or unexisting vectorization - No issue detected | 0 | 1.5 | 0 | 6.25 |
| ►21746 | libgromacs_mpi.so.7.0.0 | Partial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access. | 1002 | 1.45 | 18.18 | 9.64 |
| ○ | [SA] Too many paths (1357 paths) - Simplify control structure. There are 1357 issues ( = paths) costing 1 point, limited to 1000. | 1000 | ||||
| ○ | [SA] Non innermost loop (Outermost) - Collapse loop with innermost ones. This issue costs 2 points. | 2 | ||||
| ○ | Warning! Some static analysis are missing because the loop has too many paths. Use a higher value for --maximal_path_number option. | 0 | ||||
| ►21753 | libgromacs_mpi.so.7.0.0 | Partial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access. | 161 | 1.41 | 55.67 | 18.81 |
| ○ | [SA] Too many paths (155 paths) - Simplify control structure. There are 155 issues ( = paths) costing 1 point each with a malus of 4 points. | 159 | ||||
| ○ | [SA] Non innermost loop (Outermost) - Collapse loop with innermost ones. This issue costs 2 points. | 2 | ||||
| ○ | Warning! Some static analysis are missing because the loop has too many paths. Use a higher value for --maximal_path_number option. | 0 |