IMS: grace & keep 
    Poul-Henning Kamp 
    phk at phk.freebsd.dk
       
    Sun Mar 13 09:51:24 CET 2011
    
    
  
In message <4D7BABBF.7030106 at uplex.de>, Geoff Simmons writes:
>So: if TTL has elapsed, but Varnish finds an object in grace, and
>decides as it does now to serve it from cache, then it does so;
>otherwise Varnish uses it to attempt the conditional request (if the
>object has the headers for it).
Well, this sort of goes to the max(grace,keep) vs (grace+keep) issue.
If we make it max(grace,keep), then only keep should be considered
for IMS, and the two timers are 100% independent.
If we make it (grace+keep) they act in tandem and any object in grace
is automatically subject to IMS and you can not totally disable
IMS on an object.
Which is more intuitive ?
-- 
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    
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