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Better multiples

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Slam 2019-03-19 15:10:43 +02:00 committed by GitHub
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@ -1533,12 +1533,12 @@ Power Exact Value Approx Value Bytes
---------------------------------------------------------------
7 128
8 256
10 1024 1 thousand 1 KB
16 65,536 64 KB
20 1,048,576 1 million 1 MB
30 1,073,741,824 1 billion 1 GB
32 4,294,967,296 4 GB
40 1,099,511,627,776 1 trillion 1 TB
10 1024 1 thousand 1 KiB
16 65,536 64 KiB
20 1,048,576 1 million 1 MiB
30 1,073,741,824 1 billion 1 GiB
32 4,294,967,296 4 GiB
40 1,099,511,627,776 1 trillion 1 TiB
```
#### Source(s) and further reading
@ -1555,22 +1555,22 @@ Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 10,000 ns 10 us
Send 1 KB bytes over 1 Gbps network 10,000 ns 10 us
Read 4 KB randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD
Read 1 MB sequentially from memory 250,000 ns 250 us
Round trip within same datacenter 500,000 ns 500 us
Read 1 MB sequentially from SSD* 1,000,000 ns 1,000 us 1 ms ~1GB/sec SSD, 4X memory
Disk seek 10,000,000 ns 10,000 us 10 ms 20x datacenter roundtrip
Read 1 MB sequentially from 1 Gbps 10,000,000 ns 10,000 us 10 ms 40x memory, 10X SSD
Read 1 MB sequentially from disk 30,000,000 ns 30,000 us 30 ms 120x memory, 30X SSD
Send packet CA->Netherlands->CA 150,000,000 ns 150,000 us 150 ms
Compress 1K bytes with Zippy 10,000 ns 10 μs
Send 1 KB bytes over 1 Gbps network 10,000 ns 10 μs
Read 4 KB randomly from SSD* 150,000 ns 150 μs ~1GB/sec SSD
Read 1 MB sequentially from memory 250,000 ns 250 μs
Round trip within same datacenter 500,000 ns 500 μs
Read 1 MB sequentially from SSD* 1,000,000 ns 1,000 μs 1 ms ~1GB/sec SSD, 4X memory
Disk seek 10,000,000 ns 10,000 μs 10 ms 20x datacenter roundtrip
Read 1 MB sequentially from 1 Gbps 10,000,000 ns 10,000 μs 10 ms 40x memory, 10X SSD
Read 1 MB sequentially from disk 30,000,000 ns 30,000 μs 30 ms 120x memory, 30X SSD
Send packet CA->Netherlands->CA 150,000,000 ns 150,000 μs 150 ms
Notes
-----
1 ns = 10^-9 seconds
1 us = 10^-6 seconds = 1,000 ns
1 ms = 10^-3 seconds = 1,000 us = 1,000,000 ns
1 μs = 10^-6 seconds = 1,000 ns
1 ms = 10^-3 seconds = 1,000 μs = 1,000,000 ns
```
Handy metrics based on numbers above: