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[ 4 / 4 ] Application profile is long enough (10.04 s)
To have good quality measurements, it is advised that the application profiling time is greater than 10 seconds.
[ 3 / 3 ] Optimization level option is correctly used
[ 3.00 / 3 ] Most of time spent in analyzed modules comes from functions compiled with -g and -fno-omit-frame-pointer
-g option gives access to debugging informations, such are source locations. -fno-omit-frame-pointer improve the accuracy of callchains found during the application profiling.
[ 3 / 3 ] Host configuration allows retrieval of all necessary metrics.
[ 3.00 / 3 ] Architecture specific option -march=znver is used
[ 2 / 2 ] Application is correctly profiled ("Others" category represents 0.04 % 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
[ 1 / 1 ] Lstopo present. The Topology lstopo report will be generated.
[ 0 / 0 ] Fastmath not used
Consider to add ffast-math to compilation flags (or replace -O3 with -Ofast) to unlock potential extra speedup by relaxing floating-point computation consistency. Warning: floating-point accuracy may be reduced and the compliance to IEEE/ISO rules/specifications for math functions will be relaxed, typically 'errno' will no longer be set after calling some math functions.
[ 4 / 4 ] Enough time of the experiment time spent in analyzed loops (41.28%)
If the time spent in analyzed loops is less than 30%, standard loop optimizations will have a limited impact on application performances.
[ 0 / 4 ] CPU activity is below 90% (4.36%)
CPU cores are idle more than 10% of time. Threads supposed to run on these cores are probably IO/sync waiting. Some hints: use faster filesystems to read/write data, improve parallel load balancing and/or scheduling.
[ 0 / 4 ] A significant amount of threads are idle (95.68%)
On average, more than 10% of observed threads are idle. Such threads are probably IO/sync waiting. Some hints: use faster filesystems to read/write data, improve parallel load balancing and/or scheduling.
[ 0 / 4 ] Affinity stability is lower than 90% (4.52%)
Threads are often migrating to other CPU cores/threads. For OpenMP, typically set (OMP_PLACES=cores OMP_PROC_BIND=close) or (OMP_PLACES=threads OMP_PROC_BIND=spread). With OpenMPI + OpenMP, use --bind-to core --map-by node:PE=$OMP_NUM_THREADS --report-bindings. With IntelMPI + OpenMP, set I_MPI_PIN_DOMAIN=omp:compact or I_MPI_PIN_DOMAIN=omp:scatter and use -print-rank-map.
[ 4 / 4 ] Loop profile is not flat
At least one loop coverage is greater than 4% (5.30%), representing an hotspot for the application
[ 4 / 4 ] Enough time of the experiment time spent in analyzed innermost loops (31.28%)
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 ] Cumulative Outermost/In between loops coverage (9.99%) lower than cumulative innermost loop coverage (31.28%)
Having cumulative Outermost/In between loops coverage greater than cumulative innermost loop coverage will make loop optimization more complex
[ 3 / 3 ] Less than 10% (0.00%) is spend in BLAS1 operations
It could be more efficient to inline by hand BLAS1 operations
[ 2 / 2 ] Less than 10% (0.00%) is spend in BLAS2 operations
BLAS2 calls usually could make a poor cache usage and could benefit from inlining.
[ 2 / 2 ] Less than 10% (0.00%) is spend in Libm/SVML (special functions)
Loop ID | Analysis | Penalty Score |
---|---|---|
►Loop 390 - libboundary_conditions.so | Execution Time: 5 % - Vectorization Ratio: 77.14 % - Vector Length Use: 80.00 % | |
►Data Access Issues | 8 | |
○ | [SA] Presence of special instructions executing on a single port (BROADCAST) - Simplify data access and try to get stride 1 access. There are 8 issues (= instructions) costing 1 point each. | 8 |
►Inefficient Vectorization | 8 | |
○ | [SA] Presence of special instructions executing on a single port (BROADCAST) - Simplify data access and try to get stride 1 access. There are 8 issues (= instructions) costing 1 point each. | 8 |
►Loop 392 - libboundary_conditions.so | Execution Time: 4 % - Vectorization Ratio: 78.38 % - Vector Length Use: 81.08 % | |
►Data Access Issues | 34 | |
○ | [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 32 issues (= instructions) costing 1 point each. | 32 |
►Vectorization Roadblocks | 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 |
►Inefficient Vectorization | 32 | |
○ | [SA] Presence of special instructions executing on a single port (BROADCAST) - Simplify data access and try to get stride 1 access. There are 32 issues (= instructions) costing 1 point each. | 32 |
►Loop 389 - libboundary_conditions.so | Execution Time: 4 % - Vectorization Ratio: 91.44 % - Vector Length Use: 90.91 % | |
►Loop Computation Issues | 2 | |
○ | [SA] Presence of a large number of scalar integer instructions - Simplify loop structure, perform loop splitting or perform unroll and jam. This issue costs 2 points. | 2 |
►Control Flow Issues | 21 | |
○ | [SA] Too many paths (15 paths) - Simplify control structure. There are 15 issues ( = paths) costing 1 point each with a malus of 4 points. | 19 |
○ | [SA] Non innermost loop (InBetween) - Collapse loop with innermost ones. This issue costs 2 points. | 2 |
►Data Access Issues | 10 | |
○ | [SA] Presence of special instructions executing on a single port (BROADCAST) - Simplify data access and try to get stride 1 access. There are 8 issues (= instructions) costing 1 point each. | 8 |
○ | [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 |
►Vectorization Roadblocks | 21 | |
○ | [SA] Too many paths (15 paths) - Simplify control structure. There are 15 issues ( = paths) costing 1 point each with a malus of 4 points. | 19 |
○ | [SA] Non innermost loop (InBetween) - Collapse loop with innermost ones. This issue costs 2 points. | 2 |
►Inefficient Vectorization | 8 | |
○ | [SA] Presence of special instructions executing on a single port (BROADCAST) - Simplify data access and try to get stride 1 access. There are 8 issues (= instructions) costing 1 point each. | 8 |
►Loop 1349 - libfinite_elements.so | Execution Time: 3 % - Vectorization Ratio: 67.78 % - Vector Length Use: 41.81 % | |
►Data Access Issues | 34 | |
○ | [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 2 issues ( = data accesses) costing 2 point each. | 4 |
○ | [SA] Presence of special instructions executing on a single port (INSERT/EXTRACT, BLEND/MERGE) - Simplify data access and try to get stride 1 access. There are 30 issues (= instructions) costing 1 point each. | 30 |
►Vectorization Roadblocks | 4 | |
○ | [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 2 issues ( = data accesses) costing 2 point each. | 4 |
►Inefficient Vectorization | 30 | |
○ | [SA] Presence of special instructions executing on a single port (INSERT/EXTRACT, BLEND/MERGE) - Simplify data access and try to get stride 1 access. There are 30 issues (= instructions) costing 1 point each. | 30 |
►Loop 121 - libassembly.so | Execution Time: 2 % - Vectorization Ratio: 0.00 % - Vector Length Use: 12.50 % | |
►Loop Computation Issues | 2 | |
○ | [SA] Presence of a large number of scalar integer instructions - Simplify loop structure, perform loop splitting or perform unroll and jam. This issue costs 2 points. | 2 |
►Data Access Issues | 4 | |
○ | [SA] Presence of indirect accesses - Use array restructuring or gather instructions to lower the cost. There are 1 issues ( = indirect data accesses) costing 4 point each. | 4 |
►Vectorization Roadblocks | 4 | |
○ | [SA] Presence of indirect accesses - Use array restructuring or gather instructions to lower the cost. There are 1 issues ( = indirect data accesses) costing 4 point each. | 4 |
►Loop 581 - libfinite_elements.so | Execution Time: 2 % - Vectorization Ratio: 98.11 % - Vector Length Use: 75.71 % | |
►Data Access Issues | 25 | |
○ | [SA] Presence of special instructions executing on a single port (BLEND/MERGE, SHUFFLE/PERM) - Simplify data access and try to get stride 1 access. There are 25 issues (= instructions) costing 1 point each. | 25 |
►Inefficient Vectorization | 27 | |
○ | [SA] Presence of special instructions executing on a single port (BLEND/MERGE, SHUFFLE/PERM) - Simplify data access and try to get stride 1 access. There are 25 issues (= instructions) costing 1 point each. | 25 |
○ | [SA] Inefficient vectorization: use of masked instructions - Simplify control structure. The issue costs 2 points. | 2 |
►Loop 6969 - libfinite_elements.so | Execution Time: 2 % - Vectorization Ratio: 100.00 % - Vector Length Use: 100.00 % | |
►Data Access Issues | 4 | |
○ | [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 2 issues ( = data accesses) costing 2 point each. | 4 |
►Vectorization Roadblocks | 4 | |
○ | [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 2 issues ( = data accesses) costing 2 point each. | 4 |
►Loop 1404 - libfinite_elements.so | Execution Time: 2 % - Vectorization Ratio: 50.00 % - Vector Length Use: 56.25 % | |
►Data Access Issues | 24 | |
○ | [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 8 issues ( = data accesses) costing 2 point each. | 16 |
○ | [SA] Presence of special instructions executing on a single port (BROADCAST) - Simplify data access and try to get stride 1 access. There are 8 issues (= instructions) costing 1 point each. | 8 |
►Vectorization Roadblocks | 16 | |
○ | [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 8 issues ( = data accesses) costing 2 point each. | 16 |
►Inefficient Vectorization | 8 | |
○ | [SA] Presence of special instructions executing on a single port (BROADCAST) - Simplify data access and try to get stride 1 access. There are 8 issues (= instructions) costing 1 point each. | 8 |
►Loop 2263 - libfinite_elements.so | Execution Time: 1 % - Vectorization Ratio: 96.55 % - Vector Length Use: 76.29 % | |
►Loop Computation Issues | 2 | |
○ | [SA] Presence of a large number of scalar integer instructions - Simplify loop structure, perform loop splitting or perform unroll and jam. This issue costs 2 points. | 2 |
►Data Access Issues | 26 | |
○ | [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 (BLEND/MERGE, SHUFFLE/PERM) - Simplify data access and try to get stride 1 access. There are 24 issues (= instructions) costing 1 point each. | 24 |
►Vectorization Roadblocks | 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 |
►Inefficient Vectorization | 26 | |
○ | [SA] Presence of special instructions executing on a single port (BLEND/MERGE, SHUFFLE/PERM) - Simplify data access and try to get stride 1 access. There are 24 issues (= instructions) costing 1 point each. | 24 |
○ | [SA] Inefficient vectorization: use of masked instructions - Simplify control structure. The issue costs 2 points. | 2 |
►Loop 4878 - libfinite_elements.so | Execution Time: 1 % - Vectorization Ratio: 45.45 % - Vector Length Use: 26.28 % | |
►Loop Computation Issues | 4 | |
○ | [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 1 issues (= instructions) costing 4 points each. | 4 |
►Data Access Issues | 57 | |
○ | [SA] Presence of special instructions executing on a single port (INSERT/EXTRACT, BLEND/MERGE, BROADCAST) - Simplify data access and try to get stride 1 access. There are 55 issues (= instructions) costing 1 point each. | 55 |
○ | [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 |
►Inefficient Vectorization | 55 | |
○ | [SA] Presence of special instructions executing on a single port (INSERT/EXTRACT, BLEND/MERGE, BROADCAST) - Simplify data access and try to get stride 1 access. There are 55 issues (= instructions) costing 1 point each. | 55 |