2024 Tus sau: Elizabeth Oswald | [email protected]. Kawg hloov kho: 2024-01-13 00:07
Lub cim xeeb faib siv cov haujlwm malloc thiab calloc tsis yog muab faib rau lawv tus kheej. Li no tus txoj kev pub dawbyog siv, thaum twg qhov kev faib lub cim xeeb tshwm sim. Nws pab txo qhov khib nyiab ntawm kev nco los ntawm kev tso nws.
Yuav ua li cas faib lub cim xeeb pub dawb?
Nyob rau hauv C, lub tsev qiv ntawv muaj nuj nqi malloc yog siv los faib ib lub cim xeeb ntawm lub pob. Qhov kev pab cuam nkag mus rau qhov thaiv ntawm lub cim xeeb ntawm tus taw tes uas malloc rov qab los. Thaum lub cim xeeb tsis xav tau lawm, tus pointer raug xa mus rau dawb uas deallocates lub cim xeeb kom nws tuaj yeem siv rau lwm lub hom phiaj.
Yuav ua li cas yog tias koj tsis pub dawb faib lub cim xeeb?
Nyob rau hauv feem ntau, deallocating memory ua ntej qhov kev pab cuam tawm tsis muaj ntsiab lus. Txawm li cas los xij, OS yuav rov ua dua. Free yuav kov thiab nplooj hauv cov khoom tuag; OS yuav tsis tau. Yog vim li cas: Ceev faj nrog "cov khoom tawg" uas suav cov faib.
Puas faib lub cim xeeb kim?
Kev ntsuas tsis txaus ntseeg ntawm tus nqi faib thiab tso cov blocks loj ntawm lub cim xeeb yuav xaus tias nws raug nqi txog 7.5 μs rau txhua tus alloc / dawb khub. Txawm li cas los xij muaj peb qhov sib cais ib-MB tus nqi rau kev faib loj.
Can realloc pub dawb qhov chaw nco yog tias muaj li cas?
Lub realloc muaj nuj nqi faib, faib, lossis tso tawm qhov thaiv ntawm lub cim xeeb teev tseg los ntawm old_blk raws li cov cai hauv qab no: Yog tias old_blk yog NULL, qhov thaiv tshiab ntawm kev nco ntawm qhov loj me bytes yogfaib. Yog tias qhov loj me yog xoom, lub luag haujlwm pub dawb hu ua kom tso lub cim xeeb taw qhia los ntawm old_blk.
Pom zoo:
Koj puas siv lub cim cim ua ntej sau npe?
Txoj Cai Siv Semicolons Lub semicolon feem ntau yog siv los txuas (hauv ib kab lus) ob kab lus ywj pheej uas muaj feem cuam tshuam nrog kev xav. … Siv ib lub cim nruab nrab ntawm cov khoom hauv ib daim ntawv teev npe lossis series yog tias ib qho ntawm cov khoom muaj cov cim.
Lub sijhawm kuv lub sijhawm dawb lossis thaum kuv lub sijhawm dawb?
yog li, qhov no txhais tau tias "thaum kuv lub sijhawm dawb" tsis siv ntauthiab koj muab "hauv kuv lub sijhawm dawb" ntau dua nyob rau qhov kawg ntawm kab lus. Piv txwv li: Kuv tau taug kev tus dev thaum kuv lub sijhawm dawb.
Dab tsi yog qhov txawv ntawm cov cim thiab cov cim cim?
Symbolism yog hais txog kev siv cov duab tshwj xeeb lossis cov duab zoo nkauj, lossis cov duab kos duab pom tseeb uas tuav cov ntsiab lus sib koom hauv ib pawg. Lub cim yog ib qho duab lossis kos npe uas nkag siab los ntawm ib pawg los sawv cev rau ib yam dab tsi.
Malloc faib lub cim xeeb nyob qhov twg?
Nyob rau hauv C, lub tsev qiv ntawv muaj nuj nqi malloc yog siv los faib ib lub cim xeeb ntawm the heap. Qhov kev pab cuam nkag mus rau qhov thaiv ntawm lub cim xeeb ntawm tus taw tes uas malloc rov qab los. Thaum lub cim xeeb tsis xav tau lawm, tus pointer raug xa mus rau dawb uas deallocates lub cim xeeb kom nws siv tau rau lwm lub hom phiaj.
Rau qhov tsis tuaj yeem faib lub cim xeeb?
Yog koj tau txais qhov yuam kev=12, Tsis tuaj yeem faib lub cim xeeb lossis yuam kev=12, Tsis muaj chaw txaus, qhov no txhais tau tias koj lub cev khiav tawm ntawm lub cim xeeb lossis qhov chaw sib pauv thaum Java sim rab rawg ib txheej txheem.
