Äں˼¶Çý¶¯³ÌÐò£º¹ØÓÚÐèÒª¼«¸ßÐÔÄܵÄÓ¦Ó㬿ÉÒÔ¿ª·¢Äں˼¶Çý¶¯³ÌÐò£¬Ö±½ÓÓëÓ²¼þ½»»¥£¬¼õÉÙÖмä²ãµÄ¿ªÏú¡£ÀýÈ磬¸ßÐÔÄÜÍøÂçÉ豸»òÕßʵʱϵͳÖУ¬Äں˼¶Çý¶¯ÄÜÏÔÖøÌá¸ßÐÔÄÜ¡£
ÄÚºËÇÀÕ¼£ºÔÚʵʱϵͳÖУ¬ÄÚºËÇÀÕ¼£¨kernelpreemption£©¼¼Êõ¿ÉÒÔÈ·±£¸ßÓÅÏȼ¶ÈÎÎñÄÜʵʱÏìÓ¦£¬¼õÉÙϵͳµÄÇÀÕ¼ÑÓ³Ù¡£
Äں˹²Ïí£ºÔÚ¶àºËϵͳÖУ¬Í¨¹ýºÏÀí·ÖÅɺ͹²ÏíÄÚºË×ÊÔ´£¬¿ÉÒÔ³ä·ÖÀûÓöàºËµÄ²¢ÐÐÅÌËãÄÜÁ¦¡£ÀýÈ磬ʹÓù²ÏíÄڴ棨sharedmemory£©À´¼õÉÙͬ²½¿ªÏú¡£
CPU»º´æÓÅ»¯£ºÔÚ³ÌÐòÉè¼ÆÖУ¬¾¡Á¿¼õÉÙCPU»º´æÊ§Ð§£¨cachemiss£©£¬Í¨¹ýºÏÀíµÄ?Êý¾Ý½á¹¹ºÍ»á¼ûģʽÀ´Ìá¸ß»º´æÃüÖÐÂÊ¡£
ÄÚ´æ´ø?¿íÓëÑÓ³Ù£ºÓÅ»¯ÄÚ´æ»á¼ûµÄ·½·¨£¬¼õÉÙÄÚ´æ´ø¿íµÄÀ˷ѺÍÑÓ³Ù¡£ÀýÈ磬ʹÓÃ¶ÔÆëÄڴ棨alignedmemory£©À´Ìá¸ß»á¼ûËÙ¶È¡£
Ö¸Áî¼¶²¢ÐУºÀûÓÃCPUµÄ³¬±êÁ¿£¨superscalar£©ºÍ³¬Á÷Ë®Ïߣ¨superpipeline£©¼Ü¹¹£¬Í¨¹ýÖ¸Áî¼¶²¢?ÐУ¨instruction-levelparallelism£©À´Ìá¸ßÖ´ÐÐЧÂÊ¡£
¡°¸É±ÆÈí¼þ¡±Í¨³£¾ßÓÐÇ¿´óÇÒÅÓ´óµÄ¹¦Ð§£¬µ«?ÕæÕýÄÜÌá¸ßЧÂʵģ¬ÍùÍùÊÇÆä½¹µã¹¦Ð§¡£ÀýÈ磬ÔÚÊý¾ÝÆÊÎöÈí¼þÖУ¬ÕÆÎÕÊý¾Ýµ¼Èë¡¢ÇåÏ´¡¢´¦ÀíºÍ¿ÉÊÓ»¯µÄ½¹µã¹¦Ð§£¬¿ÉÒÔ´ó´óËõ¶ÌÊý¾Ý´¦Àíʱ¼ä¡£ÔÚÏîÄ¿ÖÎÀíÈí¼þÖУ¬Á˽âÈÎÎñÆÊÎö¡¢Ê±¼äÖÎÀíºÍ½ø¶È¸ú×ٵĽ¹µã¹¦Ð§£¬¿ÉÒÔʹÄã¸ü¸ßЧµØÍê³ÉÈÎÎñ¡£
ʲôÊÇ¡°¸É±ÆÈí¼þ¡±£¿Ëüͨ³£Ö¸ÄÇЩÔÚÐÔÄÜ¡¢¹¦Ð§ºÍÓû§ÌåÑéÉ϶¼µÖ´ïÁ˼«ÖµÄÈí¼þ¡£ÕâЩÈí¼þÍùÍù¾ßÓÐÒÔϼ¸¸ö½¹µãÌØÐÔ£º
¸ßЧÂÊ£ºÄܹ»ÔÚ¶Ìʱ¼äÄÚÍê³É´ó×ÚÈÎÎñ£¬ÏÔÖøÌáÉýÊÂÇéЧÂÊ¡£¸ßÐÔÄÜ£ºÔËÐÐËٶȿ죬ռÓÃ×ÊÔ´ÉÙ£¬Äܹ»Ôڸ߸ºÔØÏÂÎȶ¨ÔËÐС£ÖÇÄÜ»¯£ºÍ¨¹ýÈ˹¤ÖÇÄÜ»ò»úеѧϰ¼¼Êõ£¬Äܹ»×Ô¶¯»¯´¦ÀíÐí¶àÖØ¸´ÐÔÊÂÇ飬¼õÇáÓû§µ£¸º?¡£Óû§ÓѺ㺽çÃæ¼ò½à£¬²Ù×÷¼ò±ã£¬Óû§¿ÉÒÔÇáËÉÉÏÊÖ£¬²»ÐèҪ̫¶àÅàѵ¡£
ºÏÀí¼Æ»®ÈÎÎñ£ºÖƶ¨ÏêϸµÄÊÂÇ鼯»®£¬½«ÈÎÎñÆÊÎö²¢°´ÓÅÏȼ¶ÅÅÐò£¬ÓÐÖúÓÚÌá¸ßÊÂÇéЧÂÊ¡£°´ÆÚÇåÀíºÍά»¤£º°´ÆÚÇåÀí²»ÐëÒªµÄÎļþ»ººÍ´æ£¬ÓÅ»¯ÏµÍ³ÐÔÄÜ£¬¼á³ÖÈí¼þºÍϵͳµÄÎȶ¨ÔËÐС£ÀûÓÃÔÆÐ§ÀÍ£º½èÖúÔÆÐ§ÀÍ£¬¿ÉÒÔʵÏÖÊý¾ÝµÄ¿ìËÙ´æÈ¡ºÍÐͬÊÂÇ飬¼õÉÙÍâµØ´æ´¢µÄµ£¸º¡£
¼«ÖÂЧÄÜáÛ·å:½âÎö¡°¸É±ÆÈí¼þ¡±µÄ½ø½×ʹÓü¼ÇÉÓëϵͳ¼¶ÓÅ»¯
ÔÚǰһ²¿·ÖÎÒÃÇÏêϸ̽ÌÖÁË¡°¸É±ÆÈí¼þ¡±µÄ½ø½×ʹÓü¼ÇÉ£¬ÏÖÔÚÈÃÎÒÃǼÌÐøÉîÈ룬̽ÌÖÈçºÎͨ¹ýϵͳ¼¶ÓÅ»¯£¬½øÒ»²½ÌáÉýÄúµÄµçÄÔÐÔÄÜ£¬ÊµÏÖ¼«ÖÂЧÄÜ¡£
ͨ¹ý¶Ô¡°¸É±ÆÈí¼þ¡±µÄ½ø½×ʹÓü¼ÇɺÍϵͳ¼¶ÓÅ»¯µÄ̽ÌÖ£¬ÎÒÃÇ¿ÉÒÔ¿´µ½£¬ÎÞÂÛÊÇÔÚÊý¾ÝÆÊÎö¡¢±à³Ì¡¢ÏîÄ¿ÖÎÀíÕվɯäËûÁìÓò£¬³ä·ÖÀûÓÃÕâЩ¸ßЧ¹¤¾ß£¬²¢½áºÏϵͳ¼¶ÓÅ»¯²½·¥£¬¿ÉÒÔ´ó´óÌáÉýÊÂÇéЧÂÊ£¬¼õÉÙÈËΪ¹ýʧ£¬²¢ÊµÏÖ¸ü¸ßµÄÊÂÇéÖÊÁ¿¡£Òò´Ë£¬ÎÞÂÛÄãËùÔÚµÄÐÐÒµ»òÁìÓò£¬ÕÆÎÕÕâЩ¼¼ÇɺÍÒªÁì¶¼ÊÇÌáÉý¸öÈ˺ÍÍŶӾºÕùÁ¦µÄÖØÒªÍ¾¾¶¡£
Ï£ÍûÕâÆªÈíÎÄÄÜΪÄãÌṩÓмÛÖµµÄÖ¸µ¼ºÍÁé¸Ð£¬ÖúÄãÔÚÊÂÇéÖÐÈ¡µÃ¸ü´óµÄÀֳɣ¡Èç¹ûÄãÓÐÈκÎÎÊÌâ»òÐèÒª½øÒ»²½µÄ°ï?Öú£¬½Ó´ýËæÊ±ÁªÏµ¡£