openstack team mailing list archive

[Jay Pipes <jaypipes@xxxxxxxxx>]

On Wed, Dec 14, 2011 at 1:17 AM, Michael Barton
<mike-launchpad@xxxxxxxxxxxxxxxx> wrote:
> On Tue, Dec 13, 2011 at 9:21 PM, Huang Zhiteng <winston.d@xxxxxxxxx> wrote:
>> Can anyone explain why Swift doesn't want to utilize page cache _at all_?
>
> It's an artifact of the use case swift was built for - heavy on
> writes, and repeat reads (where a cache would help) are very rare.
> Having that memory available to cache dirents and inodes has a
> positive impact on performance, since a swift object server has so
> many files.
>
> The object server used to not drop caches if the file was small and
> the user wasn't authenticated, but I guess that's been factored out at
> some point.  It'd be nice to have that logic pluggable or configurable
> somehow, since it does make swift kind of useless for things it'd
> otherwise be good at, like serving static files directly to browsers.

Or static disk image files!

-jay