On Thu, May 11, 2006 at 02:30:45AM -0400, Ryan Lortie wrote: > Hello. > > Attached is a C file (and small patch) to add support for multi-file raw > images to QEMU. The rationale (for me at least) is as follows: > > I use rsync to backup my home directory. The act of starting up QEMU > changes a 20GB file on my drive. This causes 20GB of extra copying next > time I do backups. If I could split the drive image into smaller parts > (maybe 2048 10MB files) then the amount of extra copying is drastically > reduced (since only a few of these files are modified). > > There are definitely other reasons that this may be useful.
Have you tried making a read-only 'base' image and using qcow images instead? I'm not convinced that splitting things up is going to help a lot. You might end up writing 1 512 byte block each to 500 files.. in the qcow image case, that is writing 256K, and with 10mb files, that's 5GB. > o If the files comprising the device are deleted (for example) while > QEMU is running then this is quite bad. Currently this will result > in read/write requests returning -1. Maybe it makes sense to panic > and cause QEMU to exit. > at the very least, the console should print an error. If you can keep all the files open, deleting the file won't be a problem. _______________________________________________ Qemu-devel mailing list Qemu-devel@nongnu.org http://lists.nongnu.org/mailman/listinfo/qemu-devel