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&nbsp;软&nbsp;实&nbsp;时&nbsp;性&nbsp;容&nbsp;易&nbsp;满&nbsp;足&nbsp;。&nbsp;需&nbsp;要&nbsp;考&nbsp;虑&nbsp;的&nbsp;因&nbsp;素&nbsp;包&nbsp;括&nbsp;：&nbsp;上&nbsp;下&nbsp;文&nbsp;转&nbsp;换&nbsp;时&nbsp;&nbsp;<br />
间&nbsp;、&nbsp;中&nbsp;断&nbsp;延&nbsp;迟&nbsp;、&nbsp;任&nbsp;务&nbsp;的&nbsp;优&nbsp;先&nbsp;级&nbsp;和&nbsp;任&nbsp;务&nbsp;调&nbsp;度&nbsp;方&nbsp;式。上&nbsp;下&nbsp;文&nbsp;转&nbsp;换&nbsp;&nbsp;<br />
时&nbsp;间&nbsp;曾&nbsp;经&nbsp;是&nbsp;实&nbsp;时&nbsp;性&nbsp;分&nbsp;析&nbsp;的&nbsp;重&nbsp;点，&nbsp;但&nbsp;是&nbsp;因&nbsp;为CPU&nbsp;速&nbsp;度&nbsp;大&nbsp;幅&nbsp;度&nbsp;提&nbsp;高&nbsp;<br />
，&nbsp;它&nbsp;不&nbsp;再&nbsp;是&nbsp;关&nbsp;键&nbsp;问&nbsp;题。&nbsp;<br />
现&nbsp;在，严&nbsp;格&nbsp;要&nbsp;求&nbsp;的&nbsp;实&nbsp;时&nbsp;性&nbsp;任&nbsp;务&nbsp;的&nbsp;决&nbsp;定&nbsp;因&nbsp;素&nbsp;是&nbsp;中&nbsp;断&nbsp;例&nbsp;程&nbsp;本&nbsp;身&nbsp;和&nbsp;&nbsp;<br />
内&nbsp;核&nbsp;中&nbsp;的&nbsp;其&nbsp;他&nbsp;驱&nbsp;动&nbsp;程&nbsp;序&nbsp;有&nbsp;关；&nbsp;而&nbsp;响&nbsp;应&nbsp;延&nbsp;迟&nbsp;时&nbsp;间&nbsp;主&nbsp;要&nbsp;受&nbsp;中&nbsp;断&nbsp;的&nbsp;<br />
&nbsp;优&nbsp;先&nbsp;级&nbsp;和&nbsp;其&nbsp;他&nbsp;进&nbsp;程&nbsp;会&nbsp;暂&nbsp;时&nbsp;地&nbsp;关&nbsp;闭&nbsp;中&nbsp;断&nbsp;响&nbsp;应&nbsp;的&nbsp;影&nbsp;响。&nbsp;因&nbsp;此&nbsp;管&nbsp;理&nbsp;<br />
&nbsp;和&nbsp;驱&nbsp;动&nbsp;中&nbsp;断&nbsp;的&nbsp;机&nbsp;制&nbsp;必&nbsp;须&nbsp;保&nbsp;证&nbsp;实&nbsp;时&nbsp;要&nbsp;求。&nbsp;<br />
对&nbsp;于Intel&nbsp;x86&nbsp;处&nbsp;理&nbsp;器，&nbsp;实&nbsp;时&nbsp;扩&nbsp;充&nbsp;可&nbsp;以&nbsp;在Linux&nbsp;系&nbsp;统&nbsp;中&nbsp;很&nbsp;容&nbsp;易&nbsp;进&nbsp;行，&nbsp;<br />
RT-Linux&nbsp;就&nbsp;是&nbsp;很&nbsp;好&nbsp;的&nbsp;例&nbsp;子&nbsp;（见<a href="http://www.rtlinux.org/）。">http://www.rtlinux.org/）。</a>&nbsp;它&nbsp;主&nbsp;要&nbsp;是&nbsp;把&nbsp;<br />
Linux&nbsp;的&nbsp;任&nbsp;务&nbsp;作&nbsp;为&nbsp;自&nbsp;己&nbsp;的&nbsp;一&nbsp;个&nbsp;任&nbsp;务，&nbsp;因&nbsp;此&nbsp;实&nbsp;时&nbsp;性&nbsp;要&nbsp;求&nbsp;很&nbsp;高&nbsp;的&nbsp;任&nbsp;<br />
&nbsp;务&nbsp;不&nbsp;受&nbsp;非&nbsp;实&nbsp;时&nbsp;的Linux&nbsp;的&nbsp;干&nbsp;扰，可&nbsp;以&nbsp;得&nbsp;到&nbsp;满&nbsp;足。&nbsp;另&nbsp;外&nbsp;还&nbsp;提&nbsp;供&nbsp;了&nbsp;实&nbsp;<br />
&nbsp;时&nbsp;任&nbsp;务&nbsp;和Linux&nbsp;的&nbsp;基&nbsp;本&nbsp;核&nbsp;心&nbsp;和&nbsp;其&nbsp;他&nbsp;任&nbsp;务&nbsp;间&nbsp;的&nbsp;接&nbsp;口&nbsp;，&nbsp;这&nbsp;些&nbsp;接&nbsp;口&nbsp;是&nbsp;<br />
&nbsp;不&nbsp;需&nbsp;要&nbsp;很&nbsp;强&nbsp;的&nbsp;实&nbsp;时&nbsp;性。&nbsp;这&nbsp;种&nbsp;架&nbsp;构&nbsp;为&nbsp;其&nbsp;他&nbsp;的&nbsp;嵌&nbsp;入&nbsp;式&nbsp;系&nbsp;统&nbsp;提&nbsp;供&nbsp;了&nbsp;<br />
&nbsp;一&nbsp;个&nbsp;参&nbsp;考。&nbsp;关&nbsp;键&nbsp;因&nbsp;素&nbsp;就&nbsp;是&nbsp;实&nbsp;时&nbsp;性&nbsp;的&nbsp;代&nbsp;码&nbsp;和&nbsp;非&nbsp;实&nbsp;时&nbsp;代&nbsp;码&nbsp;分&nbsp;开&nbsp;设&nbsp;<br />
&nbsp;计，&nbsp;而&nbsp;且&nbsp;实&nbsp;时&nbsp;应&nbsp;用&nbsp;程&nbsp;序&nbsp;的&nbsp;处&nbsp;理&nbsp;方&nbsp;式&nbsp;和&nbsp;其&nbsp;他&nbsp;程&nbsp;序&nbsp;的&nbsp;处&nbsp;理&nbsp;方&nbsp;式&nbsp;差&nbsp;<br />
&nbsp;不&nbsp;多。&nbsp;<br />
3．&nbsp;适&nbsp;合&nbsp;嵌&nbsp;入&nbsp;式&nbsp;系&nbsp;统&nbsp;的Linux&nbsp;有一&nbsp;种&nbsp;观&nbsp;点&nbsp;认&nbsp;为&nbsp;：&nbsp;<br />
用&nbsp;户&nbsp;不&nbsp;必&nbsp;直&nbsp;接&nbsp;干&nbsp;预&nbsp;机&nbsp;器&nbsp;的&nbsp;运&nbsp;行，&nbsp;即没&nbsp;有&nbsp;用&nbsp;户&nbsp;接&nbsp;口&nbsp;的&nbsp;应&nbsp;用&nbsp;系&nbsp;统&nbsp;&nbsp;<br />
是&nbsp;嵌&nbsp;入&nbsp;式&nbsp;系&nbsp;统。&nbsp;其&nbsp;他&nbsp;的&nbsp;比&nbsp;如&nbsp;电&nbsp;梯&nbsp;控&nbsp;制&nbsp;系&nbsp;统&nbsp;应&nbsp;该&nbsp;是&nbsp;嵌&nbsp;入&nbsp;式&nbsp;系&nbsp;统&nbsp;<br />
，&nbsp;但&nbsp;是&nbsp;它&nbsp;需&nbsp;要&nbsp;人&nbsp;为&nbsp;控&nbsp;制&nbsp;。&nbsp;连&nbsp;接&nbsp;网&nbsp;络&nbsp;需&nbsp;要&nbsp;监&nbsp;视&nbsp;和&nbsp;控&nbsp;制&nbsp;网&nbsp;络&nbsp;系&nbsp;统&nbsp;<br />
&nbsp;运&nbsp;行&nbsp;的&nbsp;系&nbsp;统&nbsp;，仍&nbsp;然&nbsp;是&nbsp;嵌&nbsp;入&nbsp;式&nbsp;系&nbsp;统；&nbsp;因&nbsp;此应&nbsp;该&nbsp;根&nbsp;据&nbsp;系&nbsp;统&nbsp;的&nbsp;主&nbsp;要目&nbsp;<br />
&nbsp;的&nbsp;和&nbsp;功&nbsp;能&nbsp;来&nbsp;判&nbsp;定&nbsp;是&nbsp;否&nbsp;是&nbsp;嵌&nbsp;入&nbsp;式&nbsp;系&nbsp;统。&nbsp;<br />
最&nbsp;小&nbsp;的&nbsp;嵌&nbsp;入&nbsp;式Linux&nbsp;系&nbsp;统&nbsp;必&nbsp;须&nbsp;包&nbsp;括&nbsp;以&nbsp;下&nbsp;主&nbsp;要&nbsp;的&nbsp;要&nbsp;素：&nbsp;<br />
1．&nbsp;启&nbsp;动&nbsp;程&nbsp;序&nbsp;；&nbsp;<br />
2．融&nbsp;合&nbsp;了&nbsp;内&nbsp;存&nbsp;管&nbsp;理&nbsp;、&nbsp;进&nbsp;程&nbsp;管&nbsp;理&nbsp;和&nbsp;时&nbsp;间&nbsp;分&nbsp;批&nbsp;服&nbsp;务&nbsp;的&nbsp;核&nbsp;心；&nbsp;<br />
3．初&nbsp;始&nbsp;化&nbsp;程&nbsp;序。&nbsp;为&nbsp;了&nbsp;达&nbsp;到&nbsp;要&nbsp;求，&nbsp;而&nbsp;且&nbsp;为&nbsp;了&nbsp;保&nbsp;持&nbsp;最&nbsp;小&nbsp;系&nbsp;统，&nbsp;需&nbsp;要&nbsp;<br />
&nbsp;添&nbsp;加&nbsp;以&nbsp;下&nbsp;要&nbsp;素：&nbsp;<br />
1．&nbsp;硬&nbsp;件&nbsp;的&nbsp;驱&nbsp;动&nbsp;程&nbsp;序；&nbsp;<br />
2．&nbsp;必&nbsp;须&nbsp;的&nbsp;应&nbsp;用&nbsp;程&nbsp;序。&nbsp;根&nbsp;据&nbsp;其&nbsp;他&nbsp;需&nbsp;要，&nbsp;你&nbsp;可&nbsp;能&nbsp;增&nbsp;加&nbsp;以&nbsp;下&nbsp;功&nbsp;能：&nbsp;<br />
1．&nbsp;文&nbsp;件&nbsp;管&nbsp;理&nbsp;系&nbsp;统（&nbsp;在ROM&nbsp;或RAM中）；&nbsp;<br />
2．&nbsp;TCP/IP&nbsp;通&nbsp;讯&nbsp;协&nbsp;议；&nbsp;<br />
3．&nbsp;磁&nbsp;盘。&nbsp;<br />
4．&nbsp;选&nbsp;择&nbsp;合&nbsp;适&nbsp;的&nbsp;硬&nbsp;件&nbsp;平&nbsp;台&nbsp;选&nbsp;择&nbsp;硬&nbsp;件&nbsp;平&nbsp;台&nbsp;是&nbsp;一&nbsp;件&nbsp;很&nbsp;麻&nbsp;烦&nbsp;的&nbsp;事，受&nbsp;<br />
&nbsp;很&nbsp;多&nbsp;因&nbsp;素&nbsp;影&nbsp;响，&nbsp;比&nbsp;如&nbsp;公&nbsp;司&nbsp;的&nbsp;指&nbsp;导&nbsp;原&nbsp;则、&nbsp;个&nbsp;人&nbsp;偏&nbsp;见、&nbsp;过&nbsp;去&nbsp;产&nbsp;品&nbsp;&nbsp;<br />
的&nbsp;影&nbsp;响&nbsp;和&nbsp;消&nbsp;息&nbsp;不&nbsp;灵&nbsp;通&nbsp;等。&nbsp;费&nbsp;用&nbsp;是&nbsp;考&nbsp;虑&nbsp;的&nbsp;主&nbsp;要&nbsp;因&nbsp;素。&nbsp;提&nbsp;醒&nbsp;你&nbsp;考&nbsp;&nbsp;<br />
虑&nbsp;价&nbsp;格&nbsp;时&nbsp;不&nbsp;要&nbsp;只&nbsp;注&nbsp;意CPU&nbsp;的&nbsp;价&nbsp;钱，&nbsp;要&nbsp;对&nbsp;整&nbsp;个&nbsp;系&nbsp;统&nbsp;进&nbsp;行&nbsp;考&nbsp;虑。&nbsp;但&nbsp;&nbsp;<br />
是&nbsp;如&nbsp;果&nbsp;你&nbsp;是&nbsp;系&nbsp;统&nbsp;设&nbsp;计&nbsp;师，&nbsp;你&nbsp;必&nbsp;须&nbsp;把&nbsp;软&nbsp;件&nbsp;的&nbsp;实&nbsp;时&nbsp;性&nbsp;和&nbsp;硬&nbsp;件&nbsp;结&nbsp;合&nbsp;<br />
&nbsp;起&nbsp;来&nbsp;考&nbsp;虑。&nbsp;首&nbsp;先&nbsp;考&nbsp;虑&nbsp;需&nbsp;要&nbsp;多&nbsp;快&nbsp;的CPU，&nbsp;然&nbsp;后&nbsp;把&nbsp;选&nbsp;择&nbsp;三&nbsp;倍&nbsp;化&nbsp;的&nbsp;结&nbsp;<br />
&nbsp;果；&nbsp;因&nbsp;为&nbsp;在&nbsp;实&nbsp;际&nbsp;中应&nbsp;用&nbsp;程&nbsp;序&nbsp;会&nbsp;使&nbsp;用&nbsp;一&nbsp;些cache(&nbsp;缓&nbsp;冲)，&nbsp;所&nbsp;以&nbsp;理&nbsp;论&nbsp;<br />
&nbsp;上&nbsp;速&nbsp;度很&nbsp;快&nbsp;的CPU&nbsp;的&nbsp;实&nbsp;际&nbsp;速&nbsp;度&nbsp;会&nbsp;降&nbsp;低。&nbsp;其&nbsp;次&nbsp;考&nbsp;虑&nbsp;选&nbsp;择&nbsp;多&nbsp;快&nbsp;的BUS&nbsp;<br />
（&nbsp;总&nbsp;线）；&nbsp;如&nbsp;果&nbsp;可&nbsp;以&nbsp;包&nbsp;括&nbsp;其&nbsp;他&nbsp;的&nbsp;总&nbsp;线，&nbsp;比&nbsp;如PCI，&nbsp;就&nbsp;加&nbsp;上&nbsp;它。&nbsp;因&nbsp;&nbsp;<br />
为&nbsp;有&nbsp;时&nbsp;即&nbsp;使&nbsp;使&nbsp;用DMA&nbsp;方&nbsp;式&nbsp;传&nbsp;输，&nbsp;也&nbsp;会&nbsp;使&nbsp;快&nbsp;速CPU&nbsp;变&nbsp;得&nbsp;象&nbsp;蜗&nbsp;牛&nbsp;一&nbsp;般&nbsp;<br />
。&nbsp;选&nbsp;用&nbsp;集&nbsp;成&nbsp;外&nbsp;设&nbsp;的CPU&nbsp;比&nbsp;较&nbsp;好，而&nbsp;且&nbsp;还&nbsp;可&nbsp;选&nbsp;用&nbsp;现&nbsp;成的&nbsp;外&nbsp;设&nbsp;驱&nbsp;动&nbsp;程&nbsp;<br />
&nbsp;序&nbsp;，&nbsp;大&nbsp;大&nbsp;减&nbsp;少&nbsp;调&nbsp;试&nbsp;工&nbsp;作，&nbsp;实&nbsp;际&nbsp;上&nbsp;有&nbsp;些&nbsp;芯&nbsp;片&nbsp;集&nbsp;成&nbsp;的&nbsp;功&nbsp;能&nbsp;并&nbsp;不&nbsp;是&nbsp;<br />
&nbsp;我&nbsp;们&nbsp;所&nbsp;需&nbsp;要&nbsp;的，&nbsp;所&nbsp;以&nbsp;也&nbsp;不&nbsp;要&nbsp;认&nbsp;为&nbsp;凡&nbsp;是&nbsp;集&nbsp;成&nbsp;的&nbsp;都&nbsp;是&nbsp;好&nbsp;东&nbsp;西。&nbsp;<br />
5．&nbsp;压&nbsp;缩&nbsp;制&nbsp;作&nbsp;Linux&nbsp;系&nbsp;统&nbsp;对Linux&nbsp;的&nbsp;通&nbsp;常&nbsp;感&nbsp;觉&nbsp;是&nbsp;大，&nbsp;似&nbsp;乎&nbsp;不&nbsp;适&nbsp;合&nbsp;于&nbsp;<br />
&nbsp;嵌&nbsp;入&nbsp;式&nbsp;系&nbsp;统。&nbsp;事&nbsp;实&nbsp;并&nbsp;非&nbsp;如&nbsp;此。&nbsp;因&nbsp;为典&nbsp;型&nbsp;的&nbsp;发&nbsp;行Linux&nbsp;集&nbsp;成&nbsp;了&nbsp;很&nbsp;多&nbsp;<br />
&nbsp;桌&nbsp;面PC&nbsp;机&nbsp;需&nbsp;要&nbsp;而&nbsp;嵌&nbsp;入&nbsp;式&nbsp;系&nbsp;统&nbsp;并&nbsp;不&nbsp;需&nbsp;要&nbsp;的&nbsp;功&nbsp;能。&nbsp;首&nbsp;先&nbsp;，&nbsp;我&nbsp;们&nbsp;可&nbsp;<br />
&nbsp;以&nbsp;把&nbsp;核&nbsp;心（kernel）&nbsp;从&nbsp;其&nbsp;他&nbsp;任&nbsp;务&nbsp;中&nbsp;分&nbsp;离&nbsp;出&nbsp;来。&nbsp;标&nbsp;准&nbsp;的Linux&nbsp;核&nbsp;心&nbsp;总&nbsp;<br />
&nbsp;是&nbsp;贮&nbsp;留&nbsp;在&nbsp;内&nbsp;存&nbsp;中&nbsp;；&nbsp;当&nbsp;需&nbsp;要&nbsp;应&nbsp;用&nbsp;程&nbsp;序&nbsp;时，&nbsp;它&nbsp;把&nbsp;需&nbsp;要&nbsp;的&nbsp;程&nbsp;序&nbsp;从&nbsp;磁&nbsp;<br />
&nbsp;盘&nbsp;调&nbsp;入&nbsp;内&nbsp;存&nbsp;运&nbsp;行。&nbsp;程&nbsp;序&nbsp;运&nbsp;行&nbsp;完&nbsp;毕，&nbsp;内&nbsp;存&nbsp;清&nbsp;空，&nbsp;卸&nbsp;载&nbsp;程&nbsp;序。&nbsp;在&nbsp;嵌&nbsp;<br />
&nbsp;入&nbsp;式&nbsp;系&nbsp;统&nbsp;中&nbsp;，&nbsp;经&nbsp;常&nbsp;没&nbsp;有&nbsp;磁&nbsp;盘&nbsp;。&nbsp;目&nbsp;前&nbsp;有&nbsp;两&nbsp;种&nbsp;办&nbsp;法&nbsp;来&nbsp;处&nbsp;理&nbsp;没&nbsp;有&nbsp;&nbsp;<br />
磁&nbsp;盘&nbsp;的&nbsp;情&nbsp;况。&nbsp;对&nbsp;于&nbsp;比&nbsp;较&nbsp;简&nbsp;单&nbsp;的&nbsp;系&nbsp;统，&nbsp;核&nbsp;心（kernel）&nbsp;和&nbsp;应&nbsp;用&nbsp;程&nbsp;序&nbsp;<br />
&nbsp;同&nbsp;时&nbsp;贮&nbsp;留&nbsp;在&nbsp;内&nbsp;存&nbsp;，&nbsp;当&nbsp;系&nbsp;统&nbsp;启&nbsp;动&nbsp;时，&nbsp;就&nbsp;启&nbsp;动&nbsp;应&nbsp;用&nbsp;程&nbsp;序。&nbsp;这&nbsp;种&nbsp;方&nbsp;<br />
&nbsp;式&nbsp;和&nbsp;以&nbsp;前&nbsp;的&nbsp;嵌&nbsp;入&nbsp;式&nbsp;系&nbsp;统&nbsp;一&nbsp;样&nbsp;工&nbsp;作。Linux&nbsp;系&nbsp;统&nbsp;也&nbsp;支&nbsp;持&nbsp;这&nbsp;种&nbsp;方&nbsp;式&nbsp;<br />
。&nbsp;第&nbsp;二&nbsp;种&nbsp;方&nbsp;式&nbsp;是，&nbsp;考&nbsp;虑&nbsp;到Linux&nbsp;有load&nbsp;（&nbsp;装&nbsp;载）和unload（&nbsp;卸&nbsp;载）&nbsp;程&nbsp;&nbsp;<br />
序&nbsp;的&nbsp;能&nbsp;力，&nbsp;嵌&nbsp;入&nbsp;式&nbsp;系&nbsp;统&nbsp;也&nbsp;可&nbsp;以&nbsp;使&nbsp;用&nbsp;这&nbsp;一&nbsp;特&nbsp;点，&nbsp;来&nbsp;节&nbsp;约&nbsp;内&nbsp;存。&nbsp;假&nbsp;<br />
&nbsp;如&nbsp;有&nbsp;一&nbsp;个&nbsp;典&nbsp;型&nbsp;的&nbsp;嵌&nbsp;入&nbsp;式&nbsp;系&nbsp;统：&nbsp;包&nbsp;括8&nbsp;到16&nbsp;M&nbsp;的Flash&nbsp;Memory&nbsp;和8&nbsp;到16&nbsp;<br />
&nbsp;M&nbsp;的RAM&nbsp;；可&nbsp;以&nbsp;在Flash&nbsp;Memory上&nbsp;建&nbsp;立&nbsp;文&nbsp;件&nbsp;系&nbsp;统，&nbsp;使&nbsp;用Flash&nbsp;的&nbsp;驱&nbsp;动&nbsp;程&nbsp;<br />
&nbsp;序&nbsp;来&nbsp;驱&nbsp;动Flash&nbsp;Memory上&nbsp;文&nbsp;件&nbsp;系&nbsp;统&nbsp;工&nbsp;作。&nbsp;另&nbsp;外，&nbsp;也&nbsp;可&nbsp;以&nbsp;使&nbsp;用Flash&nbsp;D&nbsp;<br />
idsk，&nbsp;其&nbsp;中&nbsp;有&nbsp;一&nbsp;个&nbsp;例&nbsp;子&nbsp;是M－system&nbsp;的DiskOnChip，&nbsp;它&nbsp;可&nbsp;以&nbsp;支&nbsp;持达160&nbsp;M&nbsp;<br />
&nbsp;的Flash&nbsp;Disk。&nbsp;把&nbsp;使&nbsp;用&nbsp;的&nbsp;应&nbsp;用&nbsp;程&nbsp;序&nbsp;文&nbsp;件&nbsp;存&nbsp;放&nbsp;在Flash&nbsp;文&nbsp;件&nbsp;系&nbsp;统&nbsp;上，&nbsp;<br />
&nbsp;根&nbsp;据&nbsp;需&nbsp;要&nbsp;调&nbsp;入&nbsp;程&nbsp;序。&nbsp;这&nbsp;种&nbsp;动&nbsp;态&nbsp;装&nbsp;入&nbsp;方&nbsp;法&nbsp;有&nbsp;很&nbsp;多&nbsp;优&nbsp;点：&nbsp;（1）&nbsp;因&nbsp;<br />
&nbsp;为&nbsp;在Linux&nbsp;中&nbsp;有&nbsp;一&nbsp;些&nbsp;应&nbsp;用&nbsp;程&nbsp;序&nbsp;只&nbsp;是&nbsp;在&nbsp;初&nbsp;始&nbsp;化&nbsp;时&nbsp;使&nbsp;用&nbsp;一&nbsp;次，&nbsp;然&nbsp;后&nbsp;<br />
&nbsp;就&nbsp;没&nbsp;有&nbsp;用&nbsp;处&nbsp;了，&nbsp;另&nbsp;外&nbsp;它&nbsp;们&nbsp;运&nbsp;行&nbsp;方&nbsp;式&nbsp;是&nbsp;一&nbsp;个&nbsp;接&nbsp;一&nbsp;个，&nbsp;顺&nbsp;序&nbsp;进&nbsp;行&nbsp;<br />
&nbsp;的&nbsp;。可&nbsp;以&nbsp;允&nbsp;许&nbsp;初&nbsp;始&nbsp;化&nbsp;程&nbsp;序&nbsp;的代&nbsp;码&nbsp;在&nbsp;使&nbsp;用&nbsp;完&nbsp;毕&nbsp;后&nbsp;被&nbsp;废&nbsp;弃，&nbsp;不&nbsp;必&nbsp;&nbsp;<br />
永&nbsp;远&nbsp;存&nbsp;放&nbsp;在&nbsp;内&nbsp;存。因&nbsp;此&nbsp;相&nbsp;同&nbsp;内&nbsp;存&nbsp;可&nbsp;以&nbsp;运&nbsp;行&nbsp;不&nbsp;同&nbsp;的&nbsp;程&nbsp;序。&nbsp;这&nbsp;样&nbsp;很&nbsp;<br />
&nbsp;节&nbsp;省&nbsp;内&nbsp;存&nbsp;的。&nbsp;（2）&nbsp;软&nbsp;件&nbsp;更&nbsp;新&nbsp;比&nbsp;较&nbsp;容&nbsp;易；&nbsp;可&nbsp;以&nbsp;在&nbsp;系&nbsp;统&nbsp;运&nbsp;行&nbsp;的&nbsp;情&nbsp;<br />
&nbsp;况&nbsp;下&nbsp;更&nbsp;新&nbsp;应&nbsp;用&nbsp;程&nbsp;序&nbsp;和&nbsp;驱&nbsp;动&nbsp;程&nbsp;序。&nbsp;<br />
6．&nbsp;如&nbsp;何&nbsp;处&nbsp;理&nbsp;虚&nbsp;拟&nbsp;内&nbsp;存&nbsp;标&nbsp;准&nbsp;的Linux还&nbsp;有&nbsp;一&nbsp;个&nbsp;特&nbsp;点&nbsp;是&nbsp;使&nbsp;用&nbsp;虚&nbsp;拟&nbsp;内&nbsp;<br />
&nbsp;存，程&nbsp;序&nbsp;过&nbsp;大，&nbsp;可&nbsp;以&nbsp;交&nbsp;换&nbsp;到&nbsp;虚&nbsp;拟&nbsp;存&nbsp;储&nbsp;器&nbsp;上。&nbsp;这&nbsp;是&nbsp;一&nbsp;个&nbsp;神&nbsp;奇&nbsp;的&nbsp;功&nbsp;<br />
&nbsp;能&nbsp;，&nbsp;它&nbsp;使&nbsp;得&nbsp;程&nbsp;序&nbsp;有&nbsp;很&nbsp;大&nbsp;的&nbsp;运&nbsp;行&nbsp;空&nbsp;间&nbsp;。然&nbsp;而&nbsp;，&nbsp;在&nbsp;嵌&nbsp;入&nbsp;式&nbsp;系&nbsp;统&nbsp;中&nbsp;<br />
，&nbsp;这&nbsp;个&nbsp;功&nbsp;能&nbsp;似&nbsp;乎&nbsp;没&nbsp;有&nbsp;用&nbsp;武&nbsp;之&nbsp;地，&nbsp;因&nbsp;为&nbsp;没&nbsp;有&nbsp;磁&nbsp;盘。&nbsp;这&nbsp;个&nbsp;功&nbsp;能&nbsp;对&nbsp;&nbsp;<br />
于&nbsp;嵌&nbsp;入&nbsp;式&nbsp;系&nbsp;统&nbsp;，&nbsp;特&nbsp;别&nbsp;要&nbsp;求&nbsp;实&nbsp;时&nbsp;性&nbsp;很&nbsp;强&nbsp;的&nbsp;系&nbsp;统来&nbsp;说&nbsp;的&nbsp;确&nbsp;不&nbsp;那&nbsp;么&nbsp;<br />
&nbsp;重&nbsp;要，&nbsp;因&nbsp;为&nbsp;这&nbsp;个&nbsp;机&nbsp;制&nbsp;会&nbsp;浪&nbsp;花费&nbsp;时&nbsp;间，&nbsp;所&nbsp;以&nbsp;，&nbsp;嵌&nbsp;入&nbsp;式&nbsp;系&nbsp;统&nbsp;的&nbsp;应&nbsp;&nbsp;<br />
用&nbsp;程&nbsp;序&nbsp;还&nbsp;是&nbsp;在&nbsp;固&nbsp;定&nbsp;的&nbsp;地&nbsp;方&nbsp;运&nbsp;行&nbsp;比&nbsp;较&nbsp;好。&nbsp;不&nbsp;过&nbsp;提&nbsp;醒&nbsp;你&nbsp;重&nbsp;注&nbsp;意，&nbsp;&nbsp;<br />
考&nbsp;虑&nbsp;到&nbsp;一&nbsp;些CPU&nbsp;有&nbsp;这&nbsp;方&nbsp;面&nbsp;的&nbsp;特&nbsp;点，&nbsp;建&nbsp;议&nbsp;保&nbsp;留&nbsp;虚&nbsp;拟&nbsp;存&nbsp;储&nbsp;器&nbsp;的&nbsp;代&nbsp;码&nbsp;<br />
&nbsp;。&nbsp;不&nbsp;仅&nbsp;因&nbsp;为&nbsp;剔&nbsp;除&nbsp;这&nbsp;部&nbsp;分&nbsp;代&nbsp;码&nbsp;很&nbsp;费&nbsp;事&nbsp;，&nbsp;如&nbsp;果&nbsp;剔&nbsp;除&nbsp;相&nbsp;关&nbsp;代&nbsp;码&nbsp;，还&nbsp;<br />