Mailing List Archive

In message <457EEFAE.9050605 at klaus.dk>, Klaus writes:
>Hello!

>Is varnish able to serve old content if backend is slow ?
>
>I fact, the ideal way would be if content has expired, it would still
>serve the old content until new content is retrieved from backend.

The "prefetch" feature we are planning will allow you to do something
like that.

--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG | TCP/IP since RFC 956
FreeBSD committer | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.

Klaus wrote:

> I fact, the ideal way would be if content has expired, it would still
> serve the old content until new content is retrieved from backend.

I believe "pre fetching" is on the drawing board and hopefully scheduled
for version 2.

It will probably make it possible to set up rules such as: Fetch a fresh
copy from the backend 30 seconds before the object times out.

/Anton

Hello,
Something that could be usefull in a subsequent release would be
to return in case of unavailibily of the backend :
1) a stale copy for any non html object or a null sized object if that object
is not in cache.
2) a stale copy of an html url or a user defined static html page
if that html page is not in cache.
Damien,
Anton Stonor writes:
> Klaus wrote:
>
> > I fact, the ideal way would be if content has expired, it would still
> > serve the old content until new content is retrieved from backend.
>
> I believe "pre fetching" is on the drawing board and hopefully scheduled
> for version 2.
>
> It will probably make it possible to set up rules such as: Fetch a fresh
> copy from the backend 30 seconds before the object times out.
>
> /Anton
> _______________________________________________
> varnish-misc mailing list
> varnish-misc at projects.linpro.no
> http://projects.linpro.no/mailman/listinfo/varnish-misc

In message <17791.55411.360816.575367 at dwetzel@nerim.net>, Damien Wetzel writes:
>Hello,
>Something that could be usefull in a subsequent release would be
>to return in case of unavailibily of the backend :
>1) a stale copy for any non html object or a null sized object if that object
> is not in cache.
>2) a stale copy of an html url or a user defined static html page
> if that html page is not in cache.

The plan is that you will have full control over what you do in the
VCL code, including the case where the backend does not reply.

--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG | TCP/IP since RFC 956
FreeBSD committer | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.