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[ 4 / 4 ] Application profile is long enough (58.65 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 -mcpu is used
[ 2 / 2 ] Application is correctly profiled ("Others" category represents 0.68 % 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 (69.17%)
If the time spent in analyzed loops is less than 30%, standard loop optimizations will have a limited impact on application performances.
[ 3 / 4 ] CPU activity is below 90% (82.84%)
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.
[ 3 / 4 ] A significant amount of threads are idle (24.22%)
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.
[ 4 / 4 ] Affinity is good (97.78%)
Threads are not migrating to CPU cores: probably successfully pinned
[ 4 / 4 ] Loop profile is not flat
At least one loop coverage is greater than 4% (30.31%), representing an hotspot for the application
[ 4 / 4 ] Enough time of the experiment time spent in analyzed innermost loops (56.15%)
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 (13.03%) lower than cumulative innermost loop coverage (56.15%)
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% (0.69%) is spend in Libm/SVML (special functions)
Loop ID | Analysis | Penalty Score |
---|---|---|
►Loop 1751 - libiPIC3Dlib.so | Execution Time: 30 % - Vectorization Ratio: 20.00 % - Vector Length Use: 59.12 % | |
►Loop Computation Issues | 10 | |
○ | [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 2 issues (= instructions) costing 4 points each. | 8 |
○ | [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 | 42 | |
○ | [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 9 issues ( = data accesses) costing 2 point each. | 18 |
○ | [SA] Presence of indirect accesses - Use array restructuring or gather instructions to lower the cost. There are 6 issues ( = indirect data accesses) costing 4 point each. | 24 |
►Vectorization Roadblocks | 42 | |
○ | [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 9 issues ( = data accesses) costing 2 point each. | 18 |
○ | [SA] Presence of indirect accesses - Use array restructuring or gather instructions to lower the cost. There are 6 issues ( = indirect data accesses) costing 4 point each. | 24 |
►Loop 680 - libiPIC3Dlib.so | Execution Time: 20 % - Vectorization Ratio: 2.08 % - Vector Length Use: 55.21 % | |
►Data Access Issues | 56 | |
○ | [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 indirect accesses - Use array restructuring or gather instructions to lower the cost. There are 10 issues ( = indirect data accesses) costing 4 point each. | 40 |
►Vectorization Roadblocks | 56 | |
○ | [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 indirect accesses - Use array restructuring or gather instructions to lower the cost. There are 10 issues ( = indirect data accesses) costing 4 point each. | 40 |
►Loop 1750 - libiPIC3Dlib.so | Execution Time: 13 % - Vectorization Ratio: 20.35 % - Vector Length Use: 59.86 % | |
►Control Flow Issues | 4 | |
○ | [SA] Several paths (2 paths) - Simplify control structure or force the compiler to use masked instructions. There are 2 issues ( = paths) costing 1 point each. | 2 |
○ | [SA] Non innermost loop (Outermost) - Collapse loop with innermost ones. This issue costs 2 points. | 2 |
►Data Access Issues | 42 | |
○ | [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 9 issues ( = data accesses) costing 2 point each. | 18 |
○ | [SA] Presence of indirect accesses - Use array restructuring or gather instructions to lower the cost. There are 6 issues ( = indirect data accesses) costing 4 point each. | 24 |
►Vectorization Roadblocks | 46 | |
○ | [SA] Several paths (2 paths) - Simplify control structure or force the compiler to use masked instructions. There are 2 issues ( = paths) costing 1 point each. | 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 9 issues ( = data accesses) costing 2 point each. | 18 |
○ | [SA] Presence of indirect accesses - Use array restructuring or gather instructions to lower the cost. There are 6 issues ( = indirect data accesses) costing 4 point each. | 24 |
○ | [SA] Non innermost loop (Outermost) - Collapse loop with innermost ones. This issue costs 2 points. | 2 |
►Loop 1899 - libiPIC3Dlib.so | Execution Time: 2 % - Vectorization Ratio: 27.03 % - Vector Length Use: 63.18 % | |
►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 | 1 | |
○ | [SA] Presence of calls - Inline either by compiler or by hand and use SVML for libm calls. There are 1 issues (= calls) costing 1 point each. | 1 |
►Vectorization Roadblocks | 1001 | |
○ | [SA] Presence of calls - Inline either by compiler or by hand and use SVML for libm calls. There are 1 issues (= calls) costing 1 point each. | 1 |
○ | [SA] Too many paths (at least 1000 paths) - Simplify control structure. There are at least 1000 issues ( = paths) costing 1 point. | 1000 |
►Loop 1880 - libiPIC3Dlib.so | Execution Time: 0 % - Vectorization Ratio: 22.22 % - Vector Length Use: 61.11 % | |
►Loop Computation Issues | 10 | |
○ | [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 2 issues (= instructions) costing 4 points each. | 8 |
○ | [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 |
►Loop 1879 - libiPIC3Dlib.so | Execution Time: 0 % - Vectorization Ratio: 22.22 % - Vector Length Use: 61.11 % | |
►Loop Computation Issues | 6 | |
○ | [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 |
○ | [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 |
►Loop 1721 - libiPIC3Dlib.so | Execution Time: 0 % - Vectorization Ratio: 22.92 % - Vector Length Use: 56.77 % | |
►Loop Computation Issues | 34 | |
○ | [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 8 issues (= instructions) costing 4 points each. | 32 |
○ | [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 | 25 | |
○ | [SA] Presence of calls - Inline either by compiler or by hand and use SVML for libm calls. There are 1 issues (= calls) costing 1 point each. | 1 |
○ | [SA] Too many paths (20 paths) - Simplify control structure. There are 20 issues ( = paths) costing 1 point each with a malus of 4 points. | 24 |
►Vectorization Roadblocks | 25 | |
○ | [SA] Presence of calls - Inline either by compiler or by hand and use SVML for libm calls. There are 1 issues (= calls) costing 1 point each. | 1 |
○ | [SA] Too many paths (20 paths) - Simplify control structure. There are 20 issues ( = paths) costing 1 point each with a malus of 4 points. | 24 |
►Loop 1876 - libiPIC3Dlib.so | Execution Time: 0 % - Vectorization Ratio: 22.22 % - Vector Length Use: 68.75 % | |
►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 | 3 | |
○ | [SA] Presence of calls - Inline either by compiler or by hand and use SVML for libm calls. There are 1 issues (= calls) costing 1 point each. | 1 |
○ | [SA] Several paths (2 paths) - Simplify control structure or force the compiler to use masked instructions. There are 2 issues ( = paths) costing 1 point each. | 2 |
►Data Access Issues | 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 |
►Vectorization Roadblocks | 5 | |
○ | [SA] Presence of calls - Inline either by compiler or by hand and use SVML for libm calls. There are 1 issues (= calls) costing 1 point each. | 1 |
○ | [SA] Several paths (2 paths) - Simplify control structure or force the compiler to use masked instructions. There are 2 issues ( = paths) costing 1 point each. | 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 |