Splitting image files

[John Dalton]

Having discovered the hard way that large image files can possibly cause problems during defragging or, at the very least, make you wonder if the whole process has ground to a halt as the same file stays relentlessly in place, I have decided to give file splitting a try in order to produce more manageable file sizes. Two things occur to me:

1) Are there any known problems with file splitting?

2) Is there a best size? More or less by pulling the figure out of a hat, I have chosen 2GB.

[Ralphie]

Those who do use the splitting feature recommend a size of 1492 mb - easy to remember for USA folks. Three of those will fit nicely on a single dvd with not much waste.

[jmk94903]

-{ Quote: "Having discovered the hard way that large image files can possibly cause problems during defragging or, at the very least, make you wonder if the whole process has ground to a halt as the same file stays relentlessly in place, I have decided to give file splitting a try in order to produce more manageable file sizes. Two things occur to me:

1) Are there any known problems with file splitting?

2) Is there a best size? More or less by pulling the figure out of a hat, I have chosen 2GB." }-Ah yes, never try to defrag a drive with large backup images on it unless you have days and days to devote to the
project. :-)

I suggested the 1492MB size as Ralphie mentioned because it's smaller and will defrag faster although not fast.

I also put a # sign at the end of my backup filenames so that the various parts show up as mybackup#1.tib, mybackup#2.tib, etc.

[CatFan432]

-{ Quote: "Having discovered the hard way that large image files can possibly cause problems during defragging " }-

I read quite some time ago that there was nothing to be gained from defragging image files, that defragging could corrupt the files, and the best way to handle image files was to isolate them in their own partition and just leave them alone.

Is this all true? -CF

[Brian K]

-{ Quote: "I read quite some time ago that there was nothing to be gained from defragging image files, that defragging could corrupt the files, and the best way to handle image files was to isolate them in their own partition and just leave them alone.

Is this all true? -CF" }-

CatFan432,

Exactly what I do. Well almost. I set PerfectDisk to exclude the backup image folder from defragging.

[jmk94903]

-{ Quote: "I read quite some time ago that there was nothing to be gained from defragging image files, that defragging could corrupt the files, and the best way to handle image files was to isolate them in their own partition and just leave them alone.

Is this all true? -CF" }-Well, sort of. Isn't that definitive. :-)

I agree that there is nothing to be gained by defragging files that are stored in their own partition, and I agree that that would be the best situation.

If a file is corrupted by defragging, it's a hardware problem. Not defragging hides the problem which is fine since defragging is of little benefit unless the backups are stored on a data partition that has lots of other data also stored on it which might benefit from defragging. Again, this is consistent with keeping the backup files in their own partition since then there is no reason to defrag it.

Personally, I have defragged partitions with TI images many times and never had a corruption problem. However, my systems are almost all Intel motherboards which are conservatively designed.

[CatFan432]

-{ Quote: "If a file is corrupted by defragging, it's a hardware problem." }-
John,
Thanks for the reply. My incorrect assumption on this has always been that the software itself would cause the problem. -CF

[John Dalton]

-{ Quote: "Those who do use the splitting feature recommend a size of 1492 mb - easy to remember for USA folks. Three of those will fit nicely on a single dvd with not much waste." }-
Thanks for the info. So, another number that I need to remember. And why couldn't it be 1066? :)

[shieber]

While a good defragger shouldn't corrupt a file, it will not gain you much if anything in terms of obsrevable performance. If a file that takes 20 minutes to restore is in a dozen fragments, you won't see a shorter restore time if it's in 2 fragments or one piece.

If you are regularly backing up to a partition containing only or mostly jsut the large backup files, you are unlikely to developed highly fragmented files.

But defragging will takes eons, especially if you have your defragger set up for aggressive defragging, i.e., leaving no zone (or sector) unturned.

Avoid defragging backup images and enjoy life more ;-)