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Numbers every System Designer should know

Time RangeOperation
< 1 nsData transfer among CPU Registers
1 - 10 nsL1 and L2 Cache access
10 - 100 nsL3 Cache access, DRAM access(Lower limit)
100 ns - 1 µsDRAM access (Upper limit), MD5 Hash, System call
1 µs - 10 µsCopying 64 KB in memory, Context switch
10 µs - 100 µsNetwork Proxy, 1 MB data read from SSD
100 µs - 1 msIntra zone network latency, SSD write delay
1 ms - 10 msInter zone network latency, Rotational disk seek, Memcache get
10 ms - 100 msDNS lookup, 1GB data read from Main memory
100 ms - 1 sBcrypt hash, TLS handshake
> 1 sTransfer 1 GB over a network in same region