| Message ID | 1343218884-14980-4-git-send-email-stefanha@linux.vnet.ibm.com |
|---|---|
| State | New |
| Headers | show |
Am 25.07.2012 14:21, schrieb Stefan Hajnoczi: > The lazy refcounts bit indicates that this image can take advantage of > the dirty bit and that refcount updates can be postponed. > > Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> > --- > docs/specs/qcow2.txt | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/docs/specs/qcow2.txt b/docs/specs/qcow2.txt > index 339cdc1..f2f4faa 100644 > --- a/docs/specs/qcow2.txt > +++ b/docs/specs/qcow2.txt > @@ -86,7 +86,12 @@ in the description of a field. > Bitmask of compatible features. An implementation can > safely ignore any unknown bits that are set. > > - Bits 0-63: Reserved (set to 0) > + Bit 0: Lazy refcounts bit. If this bit is set then > + lazy refcount updates can be used. This means > + postponing marking the image file dirty and Not sure what was intended here, but the dirty flag isn't set anywhere yet, so you can't postpone it either. Maybe s/postponing//? > + postponing refcount metadata updates. > + > + Bits 1-63: Reserved (set to 0) > > 88 - 95: autoclear_features > Bitmask of auto-clear features. An implementation may only Kevin
On Thu, Jul 26, 2012 at 1:57 PM, Kevin Wolf <kwolf@redhat.com> wrote: > Am 25.07.2012 14:21, schrieb Stefan Hajnoczi: >> The lazy refcounts bit indicates that this image can take advantage of >> the dirty bit and that refcount updates can be postponed. >> >> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> >> --- >> docs/specs/qcow2.txt | 7 ++++++- >> 1 file changed, 6 insertions(+), 1 deletion(-) >> >> diff --git a/docs/specs/qcow2.txt b/docs/specs/qcow2.txt >> index 339cdc1..f2f4faa 100644 >> --- a/docs/specs/qcow2.txt >> +++ b/docs/specs/qcow2.txt >> @@ -86,7 +86,12 @@ in the description of a field. >> Bitmask of compatible features. An implementation can >> safely ignore any unknown bits that are set. >> >> - Bits 0-63: Reserved (set to 0) >> + Bit 0: Lazy refcounts bit. If this bit is set then >> + lazy refcount updates can be used. This means >> + postponing marking the image file dirty and > > Not sure what was intended here, but the dirty flag isn't set anywhere > yet, so you can't postpone it either. Maybe s/postponing//? Yes, s/postponing//. Stefan
diff --git a/docs/specs/qcow2.txt b/docs/specs/qcow2.txt index 339cdc1..f2f4faa 100644 --- a/docs/specs/qcow2.txt +++ b/docs/specs/qcow2.txt @@ -86,7 +86,12 @@ in the description of a field. Bitmask of compatible features. An implementation can safely ignore any unknown bits that are set. - Bits 0-63: Reserved (set to 0) + Bit 0: Lazy refcounts bit. If this bit is set then + lazy refcount updates can be used. This means + postponing marking the image file dirty and + postponing refcount metadata updates. + + Bits 1-63: Reserved (set to 0) 88 - 95: autoclear_features Bitmask of auto-clear features. An implementation may only
The lazy refcounts bit indicates that this image can take advantage of the dirty bit and that refcount updates can be postponed. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> --- docs/specs/qcow2.txt | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)