diff mbox series

qcow2: Fix cache-clean-interval documentation

Message ID 20180929095454.32066-1-lbloch@janustech.com (mailing list archive)
State New, archived
Headers show
Series qcow2: Fix cache-clean-interval documentation | expand

Commit Message

Leonid Bloch Sept. 29, 2018, 9:54 a.m. UTC
Fixing cache-clean-interval documentation following the recent change to
a default of 600 seconds on supported plarforms (only Linux currently).

Signed-off-by: Leonid Bloch <lbloch@janustech.com>
---
 docs/qcow2-cache.txt | 19 +++++++++----------
 qapi/block-core.json |  3 ++-
 qemu-options.hx      |  3 ++-
 3 files changed, 13 insertions(+), 12 deletions(-)

Comments

Eric Blake Oct. 1, 2018, 2:35 p.m. UTC | #1
On 9/29/18 4:54 AM, Leonid Bloch wrote:
> Fixing cache-clean-interval documentation following the recent change to
> a default of 600 seconds on supported plarforms (only Linux currently).
> 
> Signed-off-by: Leonid Bloch <lbloch@janustech.com>
> ---
>   docs/qcow2-cache.txt | 19 +++++++++----------
>   qapi/block-core.json |  3 ++-
>   qemu-options.hx      |  3 ++-
>   3 files changed, 13 insertions(+), 12 deletions(-)
> 
> diff --git a/docs/qcow2-cache.txt b/docs/qcow2-cache.txt
> index 59358b816f..1778312e09 100644
> --- a/docs/qcow2-cache.txt
> +++ b/docs/qcow2-cache.txt
> @@ -202,18 +202,17 @@ Reducing the memory usage
>   It is possible to clean unused cache entries in order to reduce the
>   memory usage during periods of low I/O activity.
>   
> -The parameter "cache-clean-interval" defines an interval (in seconds).
> -All cache entries that haven't been accessed during that interval are
> -removed from memory.
> +The parameter "cache-clean-interval" defines an interval (in seconds),
> +affer which all the cache entries that haven't been accessed during it

s/affer/after/

Maybe s/during it/during the interval/


> +are removed from memory. Setting this parameter to 0 disables this feature.
>   
> -This example removes all unused cache entries every 15 minutes:
> +The following example removes all unused cache entries every 15 minutes:
>   
>      -drive file=hd.qcow2,cache-clean-interval=900
>   
> -If unset, the default value for this parameter is 600. Setting it to 0
> -disables this feature.
> +If unset, the default value for this parameter is 600 on platforms which
> +support this functionality, and is 0 (disabled) on other platforms.
>   
> -Note that this functionality currently relies on the MADV_DONTNEED
> -argument for madvise() to actually free the memory. This is a
> -Linux-specific feature, so cache-clean-interval is not supported in
> -other systems.
> +This functionality currently relies on the MADV_DONTNEED argument for
> +madvise() to actually free the memory. This is a Linux-specific feature,
> +so cache-clean-interval is not supported on other systems.

Otherwise looks good.

Reviewed-by: Eric Blake <eblake@redhat.com>
Kevin Wolf Oct. 1, 2018, 4:59 p.m. UTC | #2
Am 01.10.2018 um 16:35 hat Eric Blake geschrieben:
> On 9/29/18 4:54 AM, Leonid Bloch wrote:
> > Fixing cache-clean-interval documentation following the recent change to
> > a default of 600 seconds on supported plarforms (only Linux currently).
> > 
> > Signed-off-by: Leonid Bloch <lbloch@janustech.com>
> > ---
> >   docs/qcow2-cache.txt | 19 +++++++++----------
> >   qapi/block-core.json |  3 ++-
> >   qemu-options.hx      |  3 ++-
> >   3 files changed, 13 insertions(+), 12 deletions(-)
> > 
> > diff --git a/docs/qcow2-cache.txt b/docs/qcow2-cache.txt
> > index 59358b816f..1778312e09 100644
> > --- a/docs/qcow2-cache.txt
> > +++ b/docs/qcow2-cache.txt
> > @@ -202,18 +202,17 @@ Reducing the memory usage
> >   It is possible to clean unused cache entries in order to reduce the
> >   memory usage during periods of low I/O activity.
> > -The parameter "cache-clean-interval" defines an interval (in seconds).
> > -All cache entries that haven't been accessed during that interval are
> > -removed from memory.
> > +The parameter "cache-clean-interval" defines an interval (in seconds),
> > +affer which all the cache entries that haven't been accessed during it
> 
> s/affer/after/
> 
> Maybe s/during it/during the interval/

Thanks, made these fixes and applied it to the block branch.

Kevin
Leonid Bloch Oct. 2, 2018, 9:50 a.m. UTC | #3
On 10/1/18 7:59 PM, Kevin Wolf wrote:
> Am 01.10.2018 um 16:35 hat Eric Blake geschrieben:
>> On 9/29/18 4:54 AM, Leonid Bloch wrote:
>>> Fixing cache-clean-interval documentation following the recent change to
>>> a default of 600 seconds on supported plarforms (only Linux currently).
>>>
>>> Signed-off-by: Leonid Bloch <lbloch@janustech.com>
>>> ---
>>>    docs/qcow2-cache.txt | 19 +++++++++----------
>>>    qapi/block-core.json |  3 ++-
>>>    qemu-options.hx      |  3 ++-
>>>    3 files changed, 13 insertions(+), 12 deletions(-)
>>>
>>> diff --git a/docs/qcow2-cache.txt b/docs/qcow2-cache.txt
>>> index 59358b816f..1778312e09 100644
>>> --- a/docs/qcow2-cache.txt
>>> +++ b/docs/qcow2-cache.txt
>>> @@ -202,18 +202,17 @@ Reducing the memory usage
>>>    It is possible to clean unused cache entries in order to reduce the
>>>    memory usage during periods of low I/O activity.
>>> -The parameter "cache-clean-interval" defines an interval (in seconds).
>>> -All cache entries that haven't been accessed during that interval are
>>> -removed from memory.
>>> +The parameter "cache-clean-interval" defines an interval (in seconds),
>>> +affer which all the cache entries that haven't been accessed during it
>>
>> s/affer/after/
>>
>> Maybe s/during it/during the interval/
> 
> Thanks, made these fixes and applied it to the block branch.
> 
> Kevin
> 

Thanks Kevin, Eric!
diff mbox series

Patch

diff --git a/docs/qcow2-cache.txt b/docs/qcow2-cache.txt
index 59358b816f..1778312e09 100644
--- a/docs/qcow2-cache.txt
+++ b/docs/qcow2-cache.txt
@@ -202,18 +202,17 @@  Reducing the memory usage
 It is possible to clean unused cache entries in order to reduce the
 memory usage during periods of low I/O activity.
 
-The parameter "cache-clean-interval" defines an interval (in seconds).
-All cache entries that haven't been accessed during that interval are
-removed from memory.
+The parameter "cache-clean-interval" defines an interval (in seconds),
+affer which all the cache entries that haven't been accessed during it
+are removed from memory. Setting this parameter to 0 disables this feature.
 
-This example removes all unused cache entries every 15 minutes:
+The following example removes all unused cache entries every 15 minutes:
 
    -drive file=hd.qcow2,cache-clean-interval=900
 
-If unset, the default value for this parameter is 600. Setting it to 0
-disables this feature.
+If unset, the default value for this parameter is 600 on platforms which
+support this functionality, and is 0 (disabled) on other platforms.
 
-Note that this functionality currently relies on the MADV_DONTNEED
-argument for madvise() to actually free the memory. This is a
-Linux-specific feature, so cache-clean-interval is not supported in
-other systems.
+This functionality currently relies on the MADV_DONTNEED argument for
+madvise() to actually free the memory. This is a Linux-specific feature,
+so cache-clean-interval is not supported on other systems.
diff --git a/qapi/block-core.json b/qapi/block-core.json
index 46dac23d2f..25b8a0e744 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -2895,7 +2895,8 @@ 
 #
 # @cache-clean-interval:  clean unused entries in the L2 and refcount
 #                         caches. The interval is in seconds. The default value
-#                         is 600, and 0 disables this feature. (since 2.5)
+#                         is 600 on supporting platforms, and 0 on other
+#                         platforms. 0 disables this feature. (since 2.5)
 #
 # @encrypt:               Image decryption options. Mandatory for
 #                         encrypted images, except when doing a metadata-only
diff --git a/qemu-options.hx b/qemu-options.hx
index 52d9d9f06d..f139459e80 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -747,7 +747,8 @@  it which is not used for the L2 cache)
 
 @item cache-clean-interval
 Clean unused entries in the L2 and refcount caches. The interval is in seconds.
-The default value is 600. Setting it to 0 disables this feature.
+The default value is 600 on supporting platforms, and 0 on other platforms.
+Setting it to 0 disables this feature.
 
 @item pass-discard-request
 Whether discard requests to the qcow2 device should be forwarded to the data