GCC 4.8 Optimization Levels Benchmarking various optimization levels exposed by the GCC 4.8.0 compiler for a future article on Phoronix.com. -Os: Processor: Intel Core i7-3770K @ 3.50GHz (8 Cores), Motherboard: ECS Z77H2-A2X v1.0, Chipset: Intel Xeon E3-1200 v2/3rd, Memory: 8192MB, Disk: 60GB OCZ VERTEX2, Graphics: NVIDIA GeForce GTX 550 Ti 1024MB (405/324MHz), Audio: Realtek ALC892, Monitor: DELL P2210H, Network: Realtek RTL8111/8168B + Intel Centrino Advanced-N 6205 OS: Ubuntu 13.04, Kernel: 3.8.0-4-generic (x86_64), Desktop: Unity 6.6.0, Display Server: X Server 1.13.2, Display Driver: nouveau 1.0.6, OpenGL: 3.0 Mesa 9.0.2 Gallium 0.4, Compiler: GCC 4.8.0 20130121, File-System: ext4, Screen Resolution: 1920x1080 -Og: Processor: Intel Core i7-3770K @ 3.50GHz (8 Cores), Motherboard: ECS Z77H2-A2X v1.0, Chipset: Intel Xeon E3-1200 v2/3rd, Memory: 8192MB, Disk: 60GB OCZ VERTEX2, Graphics: NVIDIA GeForce GTX 550 Ti 1024MB (405/324MHz), Audio: Realtek ALC892, Monitor: DELL P2210H, Network: Realtek RTL8111/8168B + Intel Centrino Advanced-N 6205 OS: Ubuntu 13.04, Kernel: 3.8.0-4-generic (x86_64), Desktop: Unity 6.6.0, Display Server: X Server 1.13.2, Display Driver: nouveau 1.0.6, OpenGL: 3.0 Mesa 9.0.2 Gallium 0.4, Compiler: GCC 4.8.0 20130121, File-System: ext4, Screen Resolution: 1920x1080 -O0: Processor: Intel Core i7-3770K @ 3.50GHz (8 Cores), Motherboard: ECS Z77H2-A2X v1.0, Chipset: Intel Xeon E3-1200 v2/3rd, Memory: 8192MB, Disk: 60GB OCZ VERTEX2, Graphics: NVIDIA GeForce GTX 550 Ti 1024MB (405/324MHz), Audio: Realtek ALC892, Monitor: DELL P2210H, Network: Realtek RTL8111/8168B + Intel Centrino Advanced-N 6205 OS: Ubuntu 13.04, Kernel: 3.8.0-4-generic (x86_64), Desktop: Unity 6.6.0, Display Server: X Server 1.13.2, Display Driver: nouveau 1.0.6, OpenGL: 3.0 Mesa 9.0.2 Gallium 0.4, Compiler: GCC 4.8.0 20130121, File-System: ext4, Screen Resolution: 1920x1080 -O1: Processor: Intel Core i7-3770K @ 3.50GHz (8 Cores), Motherboard: ECS Z77H2-A2X v1.0, Chipset: Intel Xeon E3-1200 v2/3rd, Memory: 8192MB, Disk: 60GB OCZ VERTEX2, Graphics: NVIDIA GeForce GTX 550 Ti 1024MB (405/324MHz), Audio: Realtek ALC892, Monitor: DELL P2210H, Network: Realtek RTL8111/8168B + Intel Centrino Advanced-N 6205 OS: Ubuntu 13.04, Kernel: 3.8.0-4-generic (x86_64), Desktop: Unity 6.6.0, Display Server: X Server 1.13.2, Display Driver: nouveau 1.0.6, OpenGL: 3.0 Mesa 9.0.2 Gallium 0.4, Compiler: GCC 4.8.0 20130121, File-System: ext4, Screen Resolution: 1920x1080 -O2: Processor: Intel Core i7-3770K @ 3.50GHz (8 Cores), Motherboard: ECS Z77H2-A2X v1.0, Chipset: Intel Xeon E3-1200 v2/3rd, Memory: 8192MB, Disk: 60GB OCZ VERTEX2, Graphics: NVIDIA GeForce GTX 550 Ti 1024MB (405/324MHz), Audio: Realtek ALC892, Monitor: DELL P2210H, Network: Realtek RTL8111/8168B + Intel Centrino Advanced-N 6205 OS: Ubuntu 13.04, Kernel: 3.8.0-4-generic (x86_64), Desktop: Unity 6.6.0, Display Server: X Server 1.13.2, Display Driver: nouveau 1.0.6, OpenGL: 3.0 Mesa 9.0.2 Gallium 0.4, Compiler: GCC 4.8.0 20130121, File-System: ext4, Screen Resolution: 1920x1080 -O3: Processor: Intel Core i7-3770K @ 3.50GHz (8 Cores), Motherboard: ECS Z77H2-A2X v1.0, Chipset: Intel Xeon E3-1200 v2/3rd, Memory: 8192MB, Disk: 60GB OCZ VERTEX2, Graphics: NVIDIA GeForce GTX 550 Ti 1024MB (405/324MHz), Audio: Realtek ALC892, Monitor: DELL P2210H, Network: Realtek RTL8111/8168B + Intel Centrino Advanced-N 6205 OS: Ubuntu 13.04, Kernel: 3.8.0-4-generic (x86_64), Desktop: Unity 6.6.0, Display Server: X Server 1.13.2, Display Driver: nouveau 1.0.6, OpenGL: 3.0 Mesa 9.0.2 Gallium 0.4, Compiler: GCC 4.8.0 20130121, File-System: ext4, Screen Resolution: 1920x1080 -Ofast: Processor: Intel Core i7-3770K @ 3.50GHz (8 Cores), Motherboard: ECS Z77H2-A2X v1.0, Chipset: Intel Xeon E3-1200 v2/3rd, Memory: 8192MB, Disk: 60GB OCZ VERTEX2, Graphics: NVIDIA GeForce GTX 550 Ti 1024MB (405/324MHz), Audio: Realtek ALC892, Monitor: DELL P2210H, Network: Realtek RTL8111/8168B + Intel Centrino Advanced-N 6205 OS: Ubuntu 13.04, Kernel: 3.8.0-4-generic (x86_64), Desktop: Unity 6.6.0, Display Server: X Server 1.13.2, Display Driver: nouveau 1.0.6, OpenGL: 3.0 Mesa 9.0.2 Gallium 0.4, Compiler: GCC 4.8.0 20130121, File-System: ext4, Screen Resolution: 1920x1080 BYTE Unix Benchmark 3.6 Computational Test: Dhrystone 2 LPS > Higher Is Better -Os .... 30147776.43 |========================================================= -Og .... 30161173.87 |========================================================= -O0 .... 30147388.73 |========================================================= -O1 .... 30150124.23 |========================================================= -O2 .... 30156066.70 |========================================================= -O3 .... 30149397.90 |========================================================= -Ofast . 30150256.37 |========================================================= GraphicsMagick 1.3.16 Operation: Blur Iterations Per Minute > Higher Is Better -Os .... 131 |================================================================ -Og .... 122 |============================================================ -O0 .... 86 |========================================== -O1 .... 131 |================================================================ -O2 .... 132 |================================================================= -O3 .... 133 |================================================================= -Ofast . 132 |================================================================= GraphicsMagick 1.3.16 Operation: Sharpen Iterations Per Minute > Higher Is Better -Os .... 82 |========================================================= -Og .... 57 |======================================== -O0 .... 51 |=================================== -O1 .... 95 |================================================================== -O2 .... 83 |========================================================== -O3 .... 83 |========================================================== -Ofast . 83 |========================================================== GraphicsMagick 1.3.16 Operation: Resizing Iterations Per Minute > Higher Is Better -Os .... 157 |============================================================== -Og .... 156 |============================================================= -O0 .... 92 |==================================== -O1 .... 165 |================================================================= -O2 .... 160 |=============================================================== -O3 .... 160 |=============================================================== -Ofast . 160 |=============================================================== GraphicsMagick 1.3.16 Operation: HWB Color Space Iterations Per Minute > Higher Is Better -Os .... 193 |============================================================= -Og .... 196 |============================================================== -O0 .... 116 |==================================== -O1 .... 196 |============================================================== -O2 .... 198 |============================================================== -O3 .... 198 |============================================================== -Ofast . 207 |================================================================= GraphicsMagick 1.3.16 Operation: Local Adaptive Thresholding Iterations Per Minute > Higher Is Better -Os .... 113 |============================================================ -Og .... 83 |============================================ -O0 .... 45 |======================== -O1 .... 119 |=============================================================== -O2 .... 123 |================================================================= -O3 .... 118 |============================================================== -Ofast . 118 |============================================================== Himeno Benchmark 3.0 Poisson Pressure Solver MFLOPS > Higher Is Better -Os .... 1186.78 |====================================== -Og .... 1073.58 |=================================== -O0 .... 441.19 |============== -O1 .... 1045.22 |================================== -O2 .... 1602.68 |==================================================== -O3 .... 1690.13 |====================================================== -Ofast . 1892.30 |============================================================= Timed PHP Compilation 5.2.9 Time To Compile Seconds < Lower Is Better -Os .... 30.32 |============================================ -Og .... 21.25 |=============================== -O0 .... 13.05 |=================== -O1 .... 27.40 |======================================== -O2 .... 35.97 |===================================================== -O3 .... 42.79 |=============================================================== -Ofast . 43.13 |=============================================================== C-Ray 1.1 Total Time Seconds < Lower Is Better -Os .... 63.86 |============================================================ -Og .... 46.54 |============================================ -O0 .... 66.50 |=============================================================== -O1 .... 47.15 |============================================= -O2 .... 45.10 |=========================================== -O3 .... 27.77 |========================== -Ofast . 29.14 |============================ Smallpt 1.0 Global Illumination Renderer; 100 Samples Seconds < Lower Is Better -Os .... 48 |================================= -Og .... 41 |============================ -O0 .... 97 |================================================================== -O1 .... 38 |========================== -O2 .... 38 |========================== -O3 .... 38 |========================== -Ofast . 36 |======================== Opus Codec Encoding 1.0.1 WAV, Opus Encode, Opus Decode Seconds < Lower Is Better -Os .... 10.00 |==================== -Og .... 11.10 |====================== -O0 .... 31.36 |=============================================================== -O1 .... 10.49 |===================== -O2 .... 9.43 |=================== -O3 .... 9.05 |================== -Ofast . 7.40 |===============