Re: [libvirt] [PATCHv3] qemu: reduce file padding requirements

On 06/10/2010 03:31 PM, Eric Blake wrote: > Followup to https://bugzilla.redhat.com/show_bug.cgi?id=599091, > commit 20206a4b, to reduce disk waste in padding. > > * src/qemu/qemu_monitor.h (QEMU_MONITOR_MIGRATE_TO_FILE_BS): Drop > back to 512. > (QEMU_MONITOR_MIGRATE_TO_FILE_TRANSFER_SIZE): New macro. > * src/qemu/qemu_driver.c (qemudDomainSaveFlag): Update comment. > * src/qemu/qemu_monitor_text.c (qemuMonitorTextMigrateToFile): Use > two invocations of dd to output non-aligned large blocks. > * src/qemu/qemu_monitor_json.c (qemuMonitorJSONMigrateToFile): > Likewise. > --- > > v2: avoid truncating regular file destination > > v3: change minimum block size from 512 to 4k, to avoid unaligned > RMW cycles on newer disks with 4k sectors > Okay, I've finally gotten around to trying this out, and in addition to reducing the file size, it also works! ACK (Note: I haven't tested saving to a block device, so I'm taking the word of the dd documentation that this works as well ;-)