R5-3600-ddr4-3600

AMD Ryzen 5 3600 6-Core testing with a MSI B450 TOMAHAWK MAX (MS-7C02) v1.0 (3.50 BIOS) and MSI AMD Radeon RX 5600 OEM/5600 XT / 5700/5700 8GB on Debian testing via the Phoronix Test Suite.

Compare your own system(s) to this result file with the Phoronix Test Suite by running the command: phoronix-test-suite benchmark 2005064-NI-2005050VE12
Jump To Table - Results

View

Do Not Show Noisy Results
Do Not Show Results With Incomplete Data
Do Not Show Results With Little Change/Spread
List Notable Results

Limit displaying results to tests within:

CPU Massive 6 Tests
Common Kernel Benchmarks 3 Tests
Memory Test Suite 6 Tests
Server CPU Tests 2 Tests

Statistics

Show Overall Harmonic Mean(s)
Show Overall Geometric Mean
Show Geometric Means Per-Suite/Category
Show Wins / Losses Counts (Pie Chart)
Normalize Results
Remove Outliers Before Calculating Averages

Graph Settings

Force Line Graphs Where Applicable
Convert To Scalar Where Applicable
Disable Color Branding
Prefer Vertical Bar Graphs

Multi-Way Comparison

Condense Multi-Option Tests Into Single Result Graphs

Table

Show Detailed System Result Table

Run Management

Highlight
Result
Hide
Result
Result
Identifier
Performance Per
Dollar
Date
Run
  Test
  Duration
AMD Ryzen 5 3600 6-Core
May 05 2020
  1 Hour, 14 Minutes
2020-05-06_R3600RX5700
May 06 2020
  1 Hour, 41 Minutes
Invert Hiding All Results Option
  1 Hour, 28 Minutes
Only show results matching title/arguments (delimit multiple options with a comma):
Do not show results matching title/arguments (delimit multiple options with a comma):


R5-3600-ddr4-3600ProcessorMotherboardChipsetMemoryDiskGraphicsAudioNetworkMonitorOSKernelDisplay ServerCompilerFile-SystemScreen ResolutionDesktopOpenGLVulkanAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX5700AMD Ryzen 5 3600 6-Core @ 3.60GHz (6 Cores / 12 Threads)ASRock B450 Pro4 (P4.10 BIOS)AMD Starship/Matisse16GBSamsung SSD 960 PRO 512GB + 1000GB Western Digital WD1002FBYS-0 + 320GB Seagate ST3320620NSASUS NVIDIA GeForce GTX 1070 8GBNVIDIA GP104 HD AudioRealtek RTL8111/8168/8411Gentoo 2.65.6.8-gentoo (x86_64)X Server 1.20.7GCC 9.3.0 + Clang 9.0.1 + LLVM 9.0.1 + CUDA 10.2ext42560x1440MSI B450 TOMAHAWK MAX (MS-7C02) v1.0 (3.50 BIOS)32GB256GB OCZ VERTEX4 + 525GB Crucial_CT525MX3 + 2 x 4001GB Seagate ST4000VN000-1H41 + 1500GB Seagate ST31500341AS + 1500GB Western Digital WD15EARX-00PMSI AMD Radeon RX 5600 OEM/5600 XT / 5700/5700 8GB (1750/875MHz)AMD Navi 10 HDMI AudioHP ZR2440wDebian testing5.5.0-2-amd64 (x86_64)GNOME Shell 3.36.1X Server 1.20.8 + Wayland4.5 Mesa 19.3.3 (LLVM 9.0.1)1.1.107GCC 9.3.01920x1200OpenBenchmarking.orgProcessor Details- Scaling Governor: acpi-cpufreq ondemand - CPU Microcode: 0x8701013Security Details- itlb_multihit: Not affected + l1tf: Not affected + mds: Not affected + meltdown: Not affected + spec_store_bypass: Mitigation of SSB disabled via prctl and seccomp + spectre_v1: Mitigation of usercopy/swapgs barriers and __user pointer sanitization + spectre_v2: Mitigation of Full AMD retpoline IBPB: conditional STIBP: conditional RSB filling + tsx_async_abort: Not affected Compiler Details- 2020-05-06_R3600RX5700: --build=x86_64-linux-gnu --disable-vtable-verify --disable-werror --enable-bootstrap --enable-checking=release --enable-clocale=gnu --enable-default-pie --enable-gnu-unique-object --enable-languages=c,ada,c++,go,brig,d,fortran,objc,obj-c++,gm2 --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-link-mutex --enable-multiarch --enable-multilib --enable-nls --enable-objc-gc=auto --enable-offload-targets=nvptx-none,hsa --enable-plugin --enable-shared --enable-threads=posix --host=x86_64-linux-gnu --program-prefix=x86_64-linux-gnu- --target=x86_64-linux-gnu --with-abi=m64 --with-arch-32=i686 --with-build-config=bootstrap-lto-lean --with-default-libstdcxx-abi=new --with-gcc-major-version-only --with-multilib-list=m32,m64,mx32 --with-target-system-zlib=auto --with-tune=generic --without-cuda-driver -v

AMD Ryzen 5 3600 6-Core vs. 2020-05-06_R3600RX5700 ComparisonPhoronix Test SuiteBaseline+10.9%+10.9%+21.8%+21.8%+32.7%+32.7%143.6%Add - Integer37.1%Add - Floating Point36.6%Triad - Floating Point35.5%Triad - Integer35.3%Memory Copy - 1024 MiB34.8%Average - Floating Point33.2%Average - Integer32.4%Copy - Floating Point31.9%Scale - Integer30.5%Scale - Floating Point29.9%Copy - Integer28.7%M.C.F.B.S - 1024 MiB23.2%Standard Memcpy23.1%219.5%Standard Memset18.6%Scale7.6%Triad4.2%Copy3.5%Add2%t-test1RAMspeed SMPRAMspeed SMPRAMspeed SMPRAMspeed SMPMBWRAMspeed SMPRAMspeed SMPRAMspeed SMPRAMspeed SMPRAMspeed SMPRAMspeed SMPMBWTinymembencht-test1TinymembenchStreamStreamStreamStreamAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX5700

R5-3600-ddr4-3600ramspeed: Add - Integerramspeed: Copy - Integerramspeed: Scale - Integerramspeed: Triad - Integerramspeed: Average - Integerramspeed: Add - Floating Pointramspeed: Copy - Floating Pointramspeed: Scale - Floating Pointramspeed: Triad - Floating Pointramspeed: Average - Floating Pointstream: Copystream: Scalestream: Triadstream: Addtinymembench: Standard Memcpytinymembench: Standard Memsetmbw: Memory Copy - 1024 MiBmbw: Memory Copy, Fixed Block Size - 1024 MiBt-test1: 1t-test1: 2cachebench: Read Cachecachebench: Write CacheAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX570032315.4527153.7027722.8232316.9629796.3332085.9327135.6927044.3232101.6829604.0420808.021715.223458.322906.110742.416616.620270.96010991.00512.4124.8392890.7030309.77503303223563.7021095.4421241.7223892.5722508.0823485.2820573.2620825.5323688.1722219.2720106.220187.022521.022455.78729.914004.815040.5938923.56717.8265.7812913.3330597.960427222OpenBenchmarking.org

RAMspeed SMP

This benchmark tests the system memory (RAM) performance. Learn more via the OpenBenchmarking.org test page.

OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Add - Benchmark: IntegerAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57007K14K21K28K35KSE +/- 37.49, N = 3SE +/- 155.71, N = 332315.4523563.701. (CC) gcc options: -O3 -march=native
OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Add - Benchmark: IntegerAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57006K12K18K24K30KMin: 32269.64 / Avg: 32315.45 / Max: 32389.76Min: 23267.34 / Avg: 23563.7 / Max: 23794.751. (CC) gcc options: -O3 -march=native

OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Copy - Benchmark: IntegerAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57006K12K18K24K30KSE +/- 27.40, N = 3SE +/- 15.76, N = 327153.7021095.441. (CC) gcc options: -O3 -march=native
OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Copy - Benchmark: IntegerAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57005K10K15K20K25KMin: 27112.57 / Avg: 27153.7 / Max: 27205.64Min: 21067.75 / Avg: 21095.44 / Max: 21122.311. (CC) gcc options: -O3 -march=native

OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Scale - Benchmark: IntegerAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57006K12K18K24K30KSE +/- 57.16, N = 3SE +/- 18.36, N = 327722.8221241.721. (CC) gcc options: -O3 -march=native
OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Scale - Benchmark: IntegerAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57005K10K15K20K25KMin: 27648.1 / Avg: 27722.82 / Max: 27835.12Min: 21221.75 / Avg: 21241.72 / Max: 21278.391. (CC) gcc options: -O3 -march=native

OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Triad - Benchmark: IntegerAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57007K14K21K28K35KSE +/- 63.58, N = 3SE +/- 9.18, N = 332316.9623892.571. (CC) gcc options: -O3 -march=native
OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Triad - Benchmark: IntegerAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57006K12K18K24K30KMin: 32209.87 / Avg: 32316.96 / Max: 32429.87Min: 23876.08 / Avg: 23892.57 / Max: 23907.791. (CC) gcc options: -O3 -march=native

OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Average - Benchmark: IntegerAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57006K12K18K24K30KSE +/- 4.53, N = 3SE +/- 11.63, N = 329796.3322508.081. (CC) gcc options: -O3 -march=native
OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Average - Benchmark: IntegerAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57005K10K15K20K25KMin: 29787.29 / Avg: 29796.33 / Max: 29801.29Min: 22486.82 / Avg: 22508.08 / Max: 22526.871. (CC) gcc options: -O3 -march=native

OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Add - Benchmark: Floating PointAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57007K14K21K28K35KSE +/- 22.70, N = 3SE +/- 208.02, N = 332085.9323485.281. (CC) gcc options: -O3 -march=native
OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Add - Benchmark: Floating PointAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57006K12K18K24K30KMin: 32045.37 / Avg: 32085.93 / Max: 32123.86Min: 23214.13 / Avg: 23485.28 / Max: 23894.121. (CC) gcc options: -O3 -march=native

OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Copy - Benchmark: Floating PointAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57006K12K18K24K30KSE +/- 30.25, N = 3SE +/- 78.94, N = 327135.6920573.261. (CC) gcc options: -O3 -march=native
OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Copy - Benchmark: Floating PointAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57005K10K15K20K25KMin: 27083.94 / Avg: 27135.69 / Max: 27188.71Min: 20415.79 / Avg: 20573.26 / Max: 20661.951. (CC) gcc options: -O3 -march=native

OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Scale - Benchmark: Floating PointAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57006K12K18K24K30KSE +/- 72.26, N = 3SE +/- 65.19, N = 327044.3220825.531. (CC) gcc options: -O3 -march=native
OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Scale - Benchmark: Floating PointAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57005K10K15K20K25KMin: 26939.91 / Avg: 27044.32 / Max: 27183.06Min: 20695.47 / Avg: 20825.53 / Max: 20898.361. (CC) gcc options: -O3 -march=native

OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Triad - Benchmark: Floating PointAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57007K14K21K28K35KSE +/- 37.34, N = 3SE +/- 132.99, N = 332101.6823688.171. (CC) gcc options: -O3 -march=native
OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Triad - Benchmark: Floating PointAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57006K12K18K24K30KMin: 32036.21 / Avg: 32101.68 / Max: 32165.52Min: 23469.24 / Avg: 23688.17 / Max: 23928.451. (CC) gcc options: -O3 -march=native

OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Average - Benchmark: Floating PointAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57006K12K18K24K30KSE +/- 16.16, N = 3SE +/- 73.04, N = 329604.0422219.271. (CC) gcc options: -O3 -march=native
OpenBenchmarking.orgMB/s, More Is BetterRAMspeed SMP 3.5.0Type: Average - Benchmark: Floating PointAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57005K10K15K20K25KMin: 29571.73 / Avg: 29604.04 / Max: 29620.95Min: 22075.55 / Avg: 22219.27 / Max: 22313.771. (CC) gcc options: -O3 -march=native

Stream

This benchmark tests the system memory (RAM) performance. Learn more via the OpenBenchmarking.org test page.

OpenBenchmarking.orgMB/s, More Is BetterStream 2013-01-17Type: CopyAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57004K8K12K16K20KSE +/- 55.59, N = 5SE +/- 6.84, N = 520808.020106.21. (CC) gcc options: -O3 -march=native -fopenmp
OpenBenchmarking.orgMB/s, More Is BetterStream 2013-01-17Type: CopyAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57004K8K12K16K20KMin: 20615.6 / Avg: 20808.04 / Max: 20960Min: 20089.9 / Avg: 20106.22 / Max: 20124.51. (CC) gcc options: -O3 -march=native -fopenmp

OpenBenchmarking.orgMB/s, More Is BetterStream 2013-01-17Type: ScaleAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57005K10K15K20K25KSE +/- 98.96, N = 5SE +/- 6.08, N = 521715.220187.01. (CC) gcc options: -O3 -march=native -fopenmp
OpenBenchmarking.orgMB/s, More Is BetterStream 2013-01-17Type: ScaleAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57004K8K12K16K20KMin: 21557.8 / Avg: 21715.24 / Max: 22090.3Min: 20170.4 / Avg: 20187.02 / Max: 20202.81. (CC) gcc options: -O3 -march=native -fopenmp

OpenBenchmarking.orgMB/s, More Is BetterStream 2013-01-17Type: TriadAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57005K10K15K20K25KSE +/- 233.32, N = 5SE +/- 5.70, N = 523458.322521.01. (CC) gcc options: -O3 -march=native -fopenmp
OpenBenchmarking.orgMB/s, More Is BetterStream 2013-01-17Type: TriadAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57004K8K12K16K20KMin: 22745.8 / Avg: 23458.26 / Max: 23983.7Min: 22507.7 / Avg: 22521.04 / Max: 22536.71. (CC) gcc options: -O3 -march=native -fopenmp

OpenBenchmarking.orgMB/s, More Is BetterStream 2013-01-17Type: AddAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57005K10K15K20K25KSE +/- 192.20, N = 5SE +/- 14.09, N = 522906.122455.71. (CC) gcc options: -O3 -march=native -fopenmp
OpenBenchmarking.orgMB/s, More Is BetterStream 2013-01-17Type: AddAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57004K8K12K16K20KMin: 22444.8 / Avg: 22906.1 / Max: 23350.9Min: 22420.3 / Avg: 22455.74 / Max: 22503.11. (CC) gcc options: -O3 -march=native -fopenmp

Tinymembench

This benchmark tests the system memory (RAM) performance. Learn more via the OpenBenchmarking.org test page.

OpenBenchmarking.orgMB/s, More Is BetterTinymembench 2018-05-28Standard MemcpyAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57002K4K6K8K10KSE +/- 12.70, N = 3SE +/- 48.07, N = 310742.48729.91. (CC) gcc options: -O2 -lm
OpenBenchmarking.orgMB/s, More Is BetterTinymembench 2018-05-28Standard MemcpyAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57002K4K6K8K10KMin: 10729.1 / Avg: 10742.4 / Max: 10767.8Min: 8635.6 / Avg: 8729.9 / Max: 8793.31. (CC) gcc options: -O2 -lm

OpenBenchmarking.orgMB/s, More Is BetterTinymembench 2018-05-28Standard MemsetAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57004K8K12K16K20KSE +/- 67.24, N = 3SE +/- 18.03, N = 316616.614004.81. (CC) gcc options: -O2 -lm
OpenBenchmarking.orgMB/s, More Is BetterTinymembench 2018-05-28Standard MemsetAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57003K6K9K12K15KMin: 16489.9 / Avg: 16616.57 / Max: 16719Min: 13969.7 / Avg: 14004.83 / Max: 14029.41. (CC) gcc options: -O2 -lm

MBW

This is a basic/simple memory (RAM) bandwidth benchmark for memory copy operations. Learn more via the OpenBenchmarking.org test page.

OpenBenchmarking.orgMiB/s, More Is BetterMBW 2018-09-08Test: Memory Copy - Array Size: 1024 MiBAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57004K8K12K16K20KSE +/- 8.11, N = 3SE +/- 10.29, N = 320270.9615040.591. (CC) gcc options: -O3 -march=native
OpenBenchmarking.orgMiB/s, More Is BetterMBW 2018-09-08Test: Memory Copy - Array Size: 1024 MiBAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57004K8K12K16K20KMin: 20255.53 / Avg: 20270.96 / Max: 20283Min: 15024.62 / Avg: 15040.59 / Max: 15059.821. (CC) gcc options: -O3 -march=native

OpenBenchmarking.orgMiB/s, More Is BetterMBW 2018-09-08Test: Memory Copy, Fixed Block Size - Array Size: 1024 MiBAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57002K4K6K8K10KSE +/- 59.95, N = 3SE +/- 19.86, N = 310991.018923.571. (CC) gcc options: -O3 -march=native
OpenBenchmarking.orgMiB/s, More Is BetterMBW 2018-09-08Test: Memory Copy, Fixed Block Size - Array Size: 1024 MiBAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57002K4K6K8K10KMin: 10897.88 / Avg: 10991 / Max: 11102.96Min: 8903.31 / Avg: 8923.57 / Max: 8963.281. (CC) gcc options: -O3 -march=native

t-test1

This is a test of t-test1 for basic memory allocator benchmarks. Note this test profile is currently very basic and the overall time does include the warmup time of the custom t-test1 compilation. Improvements welcome. Learn more via the OpenBenchmarking.org test page.

OpenBenchmarking.orgSeconds, Fewer Is Bettert-test1 2017-01-13Threads: 1AMD Ryzen 5 3600 6-Core2020-05-06_R3600RX570048121620SE +/- 0.08, N = 3SE +/- 0.29, N = 1512.4117.831. (CC) gcc options: -pthread
OpenBenchmarking.orgSeconds, Fewer Is Bettert-test1 2017-01-13Threads: 1AMD Ryzen 5 3600 6-Core2020-05-06_R3600RX5700510152025Min: 12.28 / Avg: 12.41 / Max: 12.54Min: 15.66 / Avg: 17.83 / Max: 20.091. (CC) gcc options: -pthread

OpenBenchmarking.orgSeconds, Fewer Is Bettert-test1 2017-01-13Threads: 2AMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57001.30072.60143.90215.20286.5035SE +/- 0.041, N = 3SE +/- 0.077, N = 34.8395.7811. (CC) gcc options: -pthread
OpenBenchmarking.orgSeconds, Fewer Is Bettert-test1 2017-01-13Threads: 2AMD Ryzen 5 3600 6-Core2020-05-06_R3600RX5700246810Min: 4.79 / Avg: 4.84 / Max: 4.92Min: 5.67 / Avg: 5.78 / Max: 5.931. (CC) gcc options: -pthread

CacheBench

This is a performance test of CacheBench, which is part of LLCbench. CacheBench is designed to test the memory and cache bandwidth performance Learn more via the OpenBenchmarking.org test page.

OpenBenchmarking.orgMB/s, More Is BetterCacheBenchRead CacheAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57006001200180024003000SE +/- 9.59, N = 3SE +/- 0.41, N = 32890.702913.33MIN: 2873.14 / MAX: 2911.59MIN: 2911.86 / MAX: 2914.411. (CC) gcc options: -lrt
OpenBenchmarking.orgMB/s, More Is BetterCacheBenchRead CacheAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57005001000150020002500Min: 2873.75 / Avg: 2890.7 / Max: 2906.97Min: 2912.9 / Avg: 2913.33 / Max: 2914.141. (CC) gcc options: -lrt

OpenBenchmarking.orgMB/s, More Is BetterCacheBenchWrite CacheAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57007K14K21K28K35KSE +/- 78.77, N = 3SE +/- 18.11, N = 330309.7830597.96MIN: 26417.99 / MAX: 31903.9MIN: 26739.41 / MAX: 31959.521. (CC) gcc options: -lrt
OpenBenchmarking.orgMB/s, More Is BetterCacheBenchWrite CacheAMD Ryzen 5 3600 6-Core2020-05-06_R3600RX57005K10K15K20K25KMin: 30178.81 / Avg: 30309.78 / Max: 30451.08Min: 30569.54 / Avg: 30597.96 / Max: 30631.611. (CC) gcc options: -lrt