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Change disk to HDD for clarity (#295)

pull/168/head^2
Adam Dobrawy 2020-07-11 03:01:12 +02:00 committed by GitHub
parent cbaae481a5
commit b5173d60d5
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1 changed files with 3 additions and 3 deletions
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@ -1613,9 +1613,9 @@ Read 4 KB randomly from SSD* 150,000 ns 150 us ~1GB/se
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
HDD 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
Read 1 MB sequentially from HDD 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
Notes
@ -1627,7 +1627,7 @@ Notes
Handy metrics based on numbers above:
* Read sequentially from disk at 30 MB/s
* Read sequentially from HDD at 30 MB/s
* Read sequentially from 1 Gbps Ethernet at 100 MB/s
* Read sequentially from SSD at 1 GB/s
* Read sequentially from main memory at 4 GB/s