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