📄 dhrystone.html
字号:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html><head> <title></title> <link rel="stylesheet" media="screen" type="text/css" href="./style.css" /> <link rel="stylesheet" media="screen" type="text/css" href="./design.css" /> <link rel="stylesheet" media="print" type="text/css" href="./print.css" /> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /></head><body><a href=start.html>start</a></br><h1><a name="dhrystone" id="dhrystone">Dhrystone</a></h1><div class="level1"><p> The Dhrystone benchmark was designed to test performance factors important in non numeric systems programming (operating systems, compilers, wordprocessors, etc.): </p><ul><li class="level1"><div class="li"> it contains no floating point operations; </div></li><li class="level1"><div class="li"> a considerable percentage of time is spent in string functions making the test very dependent upon the way such operations are performed (e.g. by in-line code, routines written in assembly language, etc.) making it susceptible to manufacturers ‘tweaking’ of critical routines; </div></li><li class="level1"><div class="li"> it contains hardly any tight loops so in the case of very small caches the majority of instruction accesses are will be misses; however, the situation changes radically as soon as the cache reaches a critical size and can hold the main measurement loop; </div></li><li class="level1"><div class="li"> only a small amount of global data is manipulated (as opposed to Whetstone). </div></li></ul><p> There are two versions of the Dhrystone benchmark. A depreated version 1.1 contained some ‘dead code’ which could be removed by optimising compilers. Version 2.1 corrected this and should be the version used in practice (and is the one that is in the uClinux distribution). Some manufacturers, however, still quote the (better) results of Version 1.1 so care must be taken when comparing Dhrystone performance figures to check which version was used.</p></div><!-- SECTION [1-1313] --><h2><a name="results_on_a_blackfin" id="results_on_a_blackfin">Results on a Blackfin</a></h2><div class="level2"><table class="inline"> <tr> <th class="leftalign"> Flags </th><th class="centeralign"> size </th><th class="centeralign"> Dhrystones per Second </th> </tr> <tr> <td class="leftalign"> -O0 </td><td class="centeralign"> 26128 </td><td class="centeralign"> 214592.3 </td> </tr> <tr> <td class="leftalign"> -O1 </td><td class="centeralign"> 25384 </td><td class="centeralign"> 285714.3 </td> </tr> <tr> <td class="leftalign"> -O2 </td><td class="centeralign"> 25752 </td><td class="centeralign"> 315457.4 </td> </tr> <tr> <td class="leftalign"> -O3 </td><td class="centeralign"> 26096 </td><td class="centeralign"> 378787.9 </td> </tr> <tr> <td class="leftalign"> -O3 -ffast-math </td><td class="centeralign"> 26128 </td><td class="centeralign"> 380228.1 </td> </tr></table><br /></div><!-- SECTION [1314-] --></body></html>⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -