Topic 14-15. Cache memory, cache memory functions and levels. 14-15-Mavzu. Kesh xotira, kesh xotira vazifalari va darajalari

Topic 14-15. Cache memory , cache memory functions and levels .

14-15-Mavzu. Kesh xotira, kesh xotira vazifalari va darajalari.

Plan
Cache memory , cache memory functions and levels .
Basic memory with reciprocal connection _
Reja
Kesh xotira, kesh xotira vazifalari va darajalari.
Asosiy xotira bilan o’zaro aloqasi.
Processors are always to memory relatively fast worked . Both processors and memory are in parallel improved is coming .
Conveyor and superscalar architectural , productivity very much big which was processors functional is being released . Memory devices functional manufacturers esa first galda , speed not his _ size are trying to increase . Therefore processors for both and memories performance speeds between difference is still growing .
Speed such differences due to the processor to memory to him required the word read get for appeal when a _ how many car cancel cycles ( cycles ) skip to send right is coming .
Memory to the processor relatively How slow so much so more cycles during processor uni wait stand need is happening .
Protsessorlar har doim xotiraga nisbatan tez ishlagan. Protsessorlar ham, xotira ham parallel ravishda takomillashtirilib kelinmoqda.
Konveyerli va superskalyar arxitekturali, unumdorligi juda katta bo‘lgan protsessorlar ishlab chiqarilmoqda. Xotira qurilmalarini ishlab chiqaruvchilar esa birinchi galda, tezkorlikni emas, uning hajmini oshirishga harakat qilmoqdalar. Shuning uchun ham protsessorlar va xotiralarning ishlash tezliklari orasidagi farq yana ham kattalashmoqda.
Tezliklarning bunday farqlari tufayli, protsessor xotiraga unga kerakli so‘zni o‘qib olish uchun murojaat qilganida, bir nechta mashina sikllarini (taktlarini) bekor o‘tkazib yuborishiga to‘g‘ri keladi.
Xotira protsessorga nisbatan qanchalik sekin ishlasa, shunchalik ko‘proq sikllar davomida protsessor uni kutib turishi kerak bo‘lmoqda.
That 's the problem hal to do a how many ways available . Of these one , a little big not to size has , but relatively much fast running , processor with basic memory between located from memory use ekan (Fig. 1).
Such memory cache - memory ( " cacher " - French in the language of " hiding . " the word means ). Cache- in memory application by a lot used words or basic of memory known a part stored .
Basic of memory this part of that at the time running application by more to be used possible which was part will be . This is local is called the principle .
Figure 1. Cache memory located place
Bu muammoni hal qilishning bir nechta yo‘llari mavjud. Shulardan biri, uncha katta bo‘lmagan hajmga ega, ammo nisbatan ancha tez ishlaydigan, protsessor bilan asosiy xotira orasida joylashgan xotiradan foydalanish ekan (1-rasm).
Bunday xotira kesh-xotira deb ataladi («cacher» - fransuz tilida «yashirish» degan so‘zni anglatadi). Kesh-xotirada dastur tomonidan ko‘p ishlatiladigan so‘zlar yoki asosiy xotiraning ma’lum bir qismi saqlanadi.
Asosiy xotiraning bu qismi, o‘sha paytda ishlayotgan dastur tomonidan ko‘proq foydalanilishi mumkin bo‘lgan qismi bo‘ladi. Bu lokallik tamoili deb ataladi.
1-rasm. Kesh-xotira joylashgan o‘rni
Of the processor from memory information search order :
Protsessorning xotiradan ma’lumotlarni izlash tartibi: