On Thu, Apr 26, 2007 at 12:05:04PM -0400, Jeff Dike wrote:
>
> No, I'm referring to a different file. The scenario is that you have
> a growing file in a nearly full disk with files being deleted (and
> thus space being freed) such that allocations for the growing file
> bounce back and forth between chunks.
This is an excellent question. I call this the ping-pong problem.
The solution is as Amit describes: You have a maximum of one
continuation inode per file per chunk, and you require sparse files.
Here's an example, spelled out:
Allocate file 1 in chunk A.
Grow file 1.
Chunk A fills up.
Allocate continuation inode for file 1 in chunk B.
Chunk A gets some free space.
Chunk B fills up.
Pick chunk A for allocating next block of file 1.
Try to look up a continuation inode for file 1 in chunk A.
Continuation inode for file 1 found in chunk A!
Attach newly allocated block to existing inode for file 1 in chunk A.
This is why the file format inside each chunk needs to support sparse
files.
I have a presentation that has a series of slides on problems and
potential resolutions that might help:
http://infohost.nmt.edu/~val/review/chunkfs_presentation.pdf
-VAL
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
