Copy Methods
Copy Methods
I have been using AllSync for a few days, and the backups are really slow. My needs are as follows: I am backing up a remote site (over VPN) to a local hard drive (let's call it "task X"), and I am also backing up a local drive to a NAS on the local network (let's call it "task Y"), both with copy method B, which is the default for Windows 2000.
I think I could save a lot of time by unchecking the "Overwrite file if the content of the files is different" option. With this option enabled, AllSync must scan each entire file for differences, wasting precious time. If the program doesn't check contents, each file check will take almost no time, no matter how large the file is, unless it actually must be copied.
Is the above theory correct?
Second, your statistics show that copy method B takes significantly longer than the others over a network. I don't want to lose all interactivity, so I don't want to use method A. I also noticed that method C takes longer than the others with a USB stick.
Which method do you recommend (i.e. which is fastest) for "task X", and which for "task Y"?
Assuming you're going to say method C, what settings should I use? Of course no pause, but what would be the optimal data packet size?
Thanks
I think I could save a lot of time by unchecking the "Overwrite file if the content of the files is different" option. With this option enabled, AllSync must scan each entire file for differences, wasting precious time. If the program doesn't check contents, each file check will take almost no time, no matter how large the file is, unless it actually must be copied.
Is the above theory correct?
Second, your statistics show that copy method B takes significantly longer than the others over a network. I don't want to lose all interactivity, so I don't want to use method A. I also noticed that method C takes longer than the others with a USB stick.
Which method do you recommend (i.e. which is fastest) for "task X", and which for "task Y"?
Assuming you're going to say method C, what settings should I use? Of course no pause, but what would be the optimal data packet size?
Thanks
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Re: Copy Methods
Yes.If the program doesn't check contents, each file check will take almost no time, no matter how large the file is, unless it actually must be copied. Is the above theory correct?
For "Task Y" i would use Copy method C. For "Task X" i don't know. You have to test the VPN with Copy method B and C.Which method do you recommend (i.e. which is fastest) for "task X", and which for "task Y"?
To find out the optimal data packet size you must do some copy tests with your connection (VPN, USB, Wireless...)Assuming you're going to say method C, what settings should I use? Of course no pause, but what would be the optimal data packet size?
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copy methode A uses the API "copyfile"
copy methode B uses the API "copyfileex"
copy methode C uses the API "CreateFile"
more infos about the APIs:
http://msdn.microsoft.com/library/defau ... ctions.asp
copy methode B uses the API "copyfileex"
copy methode C uses the API "CreateFile"
more infos about the APIs:
http://msdn.microsoft.com/library/defau ... ctions.asp
Last edited by Administrator on 04 Jul 2005, 14:30, edited 1 time in total.
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At this time its limited to a max. value of 999.999 bytes. If you need more.vp wrote:What is the maximum packet size possble?
This number specify the data packet size used to read from the source file to the memory and then write from the memory to the destination file.What is the significance of this number,
Maybe, i think a packet size of 999.999 bytes will not very usefull with a slow modem connection of 64kb....you have to do some copy tests to find the optimal packet size.and are there limitations to packet size based on protocol or other parameters?
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