QEMU supports detect-zeroes option since version 2.1, but we never
added support for it in libvirt. If was requested by Vasiliy Tolstov
in the list, so I just added it.
There are two discussions to be had, optionally. One is to decide
whether we should disable detect_zeros='unmap' if discard is not set
to 'unmap', but this is getting very hypervisor-specific, so I just
documented the behaviour. The other one is the naming. I described
why I made the decision for "zeros" instead of "zeroes" the decision
in the patch, but I have no problem changing it to what others like
better.
v2:
- format detect_zeroes on the command line instead of detect_zeros
v1:
-
https://www.redhat.com/archives/libvir-list/2015-December/msg00484.html
Martin Kletzander (2):
conf: Add support of zero-detection for disks
qemu: Add support for zero-detection writes
docs/formatdomain.html.in | 10 ++++++
docs/schemas/domaincommon.rng | 12 +++++++
src/conf/domain_conf.c | 23 +++++++++++++-
src/conf/domain_conf.h | 11 +++++++
src/libvirt_private.syms | 2 ++
src/qemu/qemu_capabilities.c | 2 ++
src/qemu/qemu_capabilities.h | 1 +
src/qemu/qemu_command.c | 11 +++++++
tests/qemucapabilitiesdata/caps_2.1.1-1.caps | 1 +
tests/qemucapabilitiesdata/caps_2.4.0-1.caps | 1 +
tests/qemucapabilitiesdata/caps_2.5.0-1.caps | 1 +
.../qemuxml2argv-disk-drive-detect-zeros.args | 27 ++++++++++++++++
.../qemuxml2argv-disk-drive-detect-zeros.xml | 37 ++++++++++++++++++++++
tests/qemuxml2argvtest.c | 4 +++
tests/qemuxml2xmltest.c | 1 +
15 files changed, 143 insertions(+), 1 deletion(-)
create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-disk-drive-detect-zeros.args
create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-disk-drive-detect-zeros.xml
--
2.6.4