Hardware Performance Flashcards
typical HDD seek time
4 - 15 ms [ according to wikipedia as of 2010]
Typical SSD seek time
.08 to .15 ms
the two categories of hard disk performance characteristics
access time and data transfer time
L1 cache reference
1ns
Branch mispredict
3ns
L2 cache reference
4ns [2020]
Mutex lock/unlock
17ns [20ns]
Main memory reference
100ns
Why were CPU caches invented (I.e l1, l2 etc)?
Cpu speed was improving faster than RAM (DRAM speed), so people invented CPU caches (memory inside that CPU, I.e SRAM to remove the performance bottleneck)
Name a top end consumer CPU and L1 cache size in 2021
Intel i9 9980 XE; 1MB L1
FSB
a computer communication interface (bus) (front side bus) that was often used in Intel-chip-based computers during the 1990s and 2000s
Thermal design power
sometimes called thermal design point, is the maximum amount of heat generated by a computer chip or component that the cooling system in a computer is designed to dissipate under any workload.
Typical l2 cache size 2021
256KB to 8MB
Max 2021 l3 cache size
32mb for consumer, 64 mb for server
Which caches are core specific and which are shared between the cores?
L1 and l2 are core specific. L3 is shared among the cores
S3 storage costs
2.3cents/GB/month for frequently accessed items (S3 Standard Tier)
When should s3 glacier storage be used?
For long-term data archiving that is accessed once or twice in a year and can be restored within 12 hours
S3 glacier costs
.1cent/gb/ month
Highest stock clock speed
5.5gHz
TDP
Thermal design power
L1 cache hits typically have what latency in modern high performance cores [2017]
3 to 4 cycles
Why might a program get <1 instruction per cycle?
Hyperthreading, particularly when waiting for a memory fetch
L1 cache size
8KB for intel i846 (pre 2012 think)
Typical l3 cache size
8MB to 32MB
Typical page size
4KB
2021 L1 cache size
Modern CPUs include up to 512KB of L1 cache (64KB per core) for flagship processors while server parts feature almost twice as much
2021 l2 cache size for flagship CPUs
They range from 4-8MB on flagship CPUs (512KB per core)
Why do AMD’s Ryzen CPUs have a much larger cache size compared to rival Intel chips?
because of the MCM design vs Monolithic on the Intel side
