On Oct 9, 2014, at 6:08 PM, Shu Kit Chan <chanshu...@gmail.com> wrote:
> It seems to be similar to this jira ticket - > https://issues.apache.org/jira/browse/TS-1463 Yeah, Kit is spot on. This is a known problem with the plugin, and it’s an artifact of how the ATS cache works. To be able to implement stale-while-revalidate, we’d need to make changes in the cache such that it does not update the dir entries etc. until the “new” version is available to be served. Alan? — leif > > Kit > > On Thu, Oct 9, 2014 at 3:53 PM, Jared Ocker <oc...@ohsu.edu> wrote: > >> We have the stale-while-revalidate plugin in place and have noticed some >> behavior that seems suboptimal. While cache is fresh, everything works >> great. The first page hit after our 300sec s-maxage has passed comes back >> with “Warning: 110 Response is stale” as expected. However, it appears to >> be deleting the cached file and then looking at the origin server to pull >> fresh content. Our origin servers aren’t exactly fast (hence the need for >> ATS), so this results in about 4 sec of time while that cache file doesn’t >> exist and any hits to that page need to wait for the content from the >> origin server. >> >> Additional information: >> s-maxage=300 >> stale-while-revalidate=604800 >> stale-if-error=31536000 >> >> When Age < s-maxage: >> >> * Via: ApacheTrafficServer/4.2.0 [cHs f] >> >> First page load after Age > s-maxage: >> >> * Via: ApacheTrafficServer/4.2.0 [cHs f] >> * Warning: 110 Response is stale >> >> At this point, Cache Inspector shows the cached file to be missing for 3-4 >> seconds >> >> Subsequent page loads during revalidation process: >> >> * Via: ApacheTrafficServer/4.2.0 [cMs Sf] >> * This page load also shows a cookie being loaded that only comes from >> our origin servers >> >> After the 3-4 second revalidation process, everything seems to go back to >> normal. >> >> I might just be missing something but this doesn’t appear to be working as >> designed. Does anyone know how I can get it to continue showing stale >> cache during the entire revalidation process? >> >> Thanks, >> .: Jared >>
