【在 F***Q 的大作中提到】 : : esata or USB3? they are hugely different
F*Q
4 楼
from the specs, they are similar, but from my experience, esata is a lot faster than USB3. esata is basically sata with a different cable. with an SSD drive, I was able to get 500MB/s speed when cloning between two SSDs. for an external USB3 drive (non-ssd), I was only able to get ~60 MB/s (reported by iotop in Ubuntu) curious what other people got for USB3 external drive (ssd or non-ssd) in terms of speed.
【在 F***Q 的大作中提到】 : : from the specs, they are similar, but from my experience, esata is a lot : faster than USB3. : esata is basically sata with a different cable. with an SSD drive, I was : able to get 500MB/s speed when cloning between two SSDs. for an external : USB3 drive (non-ssd), I was only able to get ~60 MB/s (reported by iotop in : Ubuntu) : curious what other people got for USB3 external drive (ssd or non-ssd) in : terms of speed.
F*Q
6 楼
just did the following test: copy ubuntu-14.04.1-desktop-amd64.iso (975 MB) from an SSD drive to a USB3 external drive (Seagate backup plus drive, non-ssd), it took 11.35 seconds. iotop reported 85 MB/s, matching the speed from 975/11.35. copying the same file to another folder on the same ssd drive took only 1.5 to 2.1 seconds, yielding a speed of 975/2.1=451 MB/s. how long does it take for you to copy that file? you can download a similar file from http://ftp.riken.jp/Linux/ubuntu-releases/14.04.1/ubuntu-14.04-desktop-i386.iso
【在 a******n 的大作中提到】 : 我的3.0有300 - 400 MB/s 里头用的840 evo 感觉你这个不是3.0的速度 : : in
a*n
7 楼
你的85MB是机械硬盘吧 ssd同一个盘拷速度很快啊,用的什么型号,也是SATA? 我的三个盘 SATA 850a (256gb满) 850b (1tb空) USB 840 (256gb空) SATA SATA: 850 b to 850 a 1.891s 平均516 MB/s 但是如果850 b to 850 b 就要4.672s 平均209 MB/s 同时读写速度减半还多 SATA USB 3.0: 850 b to 840 2.500s 平均390 MB/s 反过来 840 to 850 b 2.453s 平均397 MB/s 然后840 to 840 要5.109s 平均190 MB/s 另外试了下 SATA -> USB 3.1 SATA 850 b to 840 USB3.1 2.203s 平均443 MB/s 觉得450 MB/s可能840到顶了,3.1应该能更快些
. 5 similar
【在 F***Q 的大作中提到】 : : just did the following test: : copy ubuntu-14.04.1-desktop-amd64.iso (975 MB) from an SSD drive to a USB3 : external drive (Seagate backup plus drive, non-ssd), it took 11.35 seconds. : iotop reported 85 MB/s, matching the speed from 975/11.35. : copying the same file to another folder on the same ssd drive took only 1.5 : to 2.1 seconds, yielding a speed of 975/2.1=451 MB/s. : how long does it take for you to copy that file? you can download a similar : file from : http://ftp.riken.jp/Linux/ubuntu-releases/14.04.1/ubuntu-14.04-desktop-i386.iso
F*Q
8 楼
that's correct. I believe it is a 2T 5400rpm mechanical drive made by Seagate. the SSD is also made by seagate https://www.amazon.com/Seagate-2-5-Inch-Z-Height-Solid-ST480HM000/dp/ B00CKAOWB6 very informative! this seems to be clear - the bottleneck of using an external drive is the max disk read/write speed, instead of the interface. Your benchmark does show that the SATA interface can be 30% faster.
【在 a******n 的大作中提到】 : 你的85MB是机械硬盘吧 ssd同一个盘拷速度很快啊,用的什么型号,也是SATA? : 我的三个盘 : SATA 850a (256gb满) 850b (1tb空) : USB 840 (256gb空) : SATA SATA: : 850 b to 850 a 1.891s 平均516 MB/s : 但是如果850 b to 850 b 就要4.672s 平均209 MB/s 同时读写速度减半还多 : SATA USB 3.0: : 850 b to 840 2.500s 平均390 MB/s : 反过来
z*8
9 楼
你这不是废话么 瓶颈又不是USB3.0 你那个拷贝慢 瓶颈在希捷机械盘
【在 F***Q 的大作中提到】 : : that's correct. I believe it is a 2T 5400rpm mechanical drive made by : Seagate. : the SSD is also made by seagate : https://www.amazon.com/Seagate-2-5-Inch-Z-Height-Solid-ST480HM000/dp/ : B00CKAOWB6 : very informative! this seems to be clear - the bottleneck of using an : external drive is the max disk read/write speed, instead of the interface. : Your benchmark does show that the SATA interface can be 30% faster.