+1 vote for this feature. -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/498523
Title: Add on-line write compression support to qcow2 Status in QEMU: Confirmed Bug description: This is a wishlist item. Launchpad really need a way for the submitter to indicate this. It would be really cool if qemu were to support disk compression on- line for writes. I know this wouldn't be really easy. Although most OS's use blocks, you can really only count on being able to compress 512-byte sectors, which doesn't give much room for a good compression ratio. Moreover, the index indicating where in the image file each sector is located would be complex to manage, since the compressed blocks would be variable sized, and you'd be wanting to do some kind of best-fit allocation of space in the image file. (If you were to make the image file compressed block size granularity, say, 64 bytes, you could probably do this best fit O(1).) If you were to buffer enough writes, you could group arbitrary sequences of written sectors into blocks to compress (which with writeback could be sent to a helper thread on another CPU, so the throughput would be good). To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/498523/+subscriptions
