Speed



  • I have noticed that no matter how many computers we image over a 1GB connection that the chart on the homepage of the gui never gets about 8mbps. Is this an incorrect reading and it is really going faster, or is there some kind of limit on how fast an image can go? We are using Sata 6 Gbps Sas drives…


  • Moderator

    Theoretically, maybe. But you’ve got to give a % of that 1GB to management and overhead. Same with the disk systems. If you are servicing 1 client, and the file is completely defragmented on the source drive and the system never has to read anything but a sequential sector on the disk, and, and, and…

    If you image (unicast, not multicast) more than 1 client, you are stressing the disk system on the server and the network switch and you’re speeds will go down.

    I can image about 14 Fujitsu laptops on a gigabit switch, each getting about 1.3GB per minute per client according to the clients. I can image about 30 acer tablets that are 100Mbps before I get below 1GB per minute per client.

    I can do this because the disk system on the server is six 10K rpm disks in RAID 5 mode optimized for read throughput. My first test server was a desktop machine with a single 3GB sata drive, and I got 4GB per minute with 1 client, but it dropped to 1GB per minute by adding the 2nd client. The disk couldn’t handle the read requests from the 2nd client as well as a real server that has a raid controller with built in cache and multiple disks to read from.



  • Thank you for your speedy reply. However I don’t think I completely understand. A 1Gbps network connection with 6Gbps sata drives on both end would lead me to believe that the max speed available is 1Gbps, making it 60Gbpm. Is this incorrect?


  • Moderator

    You’ll be limited by the disk read throughput on the server, the network bandwidth, and the disk write throughput on the hosts. Look at the hosts as they image for a more accurate speed. Imaging 1 machine from my server over 1GB links, I get about 4.3GB per minute max sustained over the 12 or so minutes it takes to image one of these machines.


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