Re: [Qemu-devel] [PATCH v3 4/5] qcow2: Set the default cache-clean-interval to 30 seconds

[Leonid Bloch]

On 08/08/2018 02:57 PM, Alberto Garcia wrote:
> On Wed 08 Aug 2018 01:49:08 PM CEST, Leonid Bloch wrote:
> > On 08/08/2018 02:47 PM, Alberto Garcia wrote:
> > > On Wed 08 Aug 2018 09:10:50 AM CEST, Leonid Bloch wrote:
> > > > The default cache-clean-interval is set to 30 seconds, in order to lower
> > > > the overhead of the qcow2 caches (before the default was 0, i.e.
> > > > disabled).
> > > >
> > > > Signed-off-by: Leonid Bloch <address@hidden>
> > >
> > > Reviewed-by: Alberto Garcia <address@hidden>
> > >
> > > > +#define DEFAULT_CACHE_CLEAN_INTERVAL 30  /* seconds */
> > >
> > > I wonder if it shouldn't be a bit higher, though. Isn't 30 seconds too
> > > low for a default?
> >
> > I also had this thought. What would you suggest?
>
> I don't know, 5 minutes at least. It should discard cache entries that
> haven't been used in a while.
>
> It my opinion the default should be for saving memory in VMs that are
> mostly idle. If the VM is more or less active I wouldn't want to clean
> cache entries that are used frequently.

How about 10 minutes?

Leonid.

> Berto