Background Fetch plugin takes care of that issue for you and won't allow more
than one download for the same object (cache key) at a time. We use that in
production (and I think/know a few other significant deployments do as well)
and don't see any issues with fd exhaustion or multiple downloads for the same
file.
The only drawback (if you can call it so) with the solution is that, you may
potentially waste bandwidth/cache space for a really large object which may not
be requested by clients often.
Thanks,
Sudheer
On Thursday, August 6, 2015 8:24 AM, Madhava Gaikwad (madgaikw)
<[email protected]> wrote:
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{}#yiv9500072116 Thanks Sudhir for the response. If too many clients starts
doing range requests or even a single client starts sending multiple range
requests, using background fetch, may cause multiple downloads to start, reason
being downloads will not be sharable. Keeping rest of the client connection
idle till, first download completes also not useful as it may cause FD
exhaustion for smaller footprint devices. I may be talking too much without
knowing much about implementation details. Thank you. Madhava From:
Sudheer Vinukonda [mailto:[email protected]]
Sent: Thursday, August 06, 2015 8:36 PM
To: [email protected]
Subject: Re: partial object caching As of v6.0, ATS does not support Partial
object caching (ala byte range caching). However, ATS does support returning
partial byte range responses if the whole object is already cached.Background
Fetch plugin takes advantage of this fact, by initiating a full object download
in the background on receiving a byte range request for an object that's not in
the cache yet. Once the full object is downloaded and populated into the cache,
subsequent byte range requests are directly served from the cache.
Thanks, Sudheer On Thursday, August 6, 2015 12:34 AM, Madhava Gaikwad
(madgaikw) <[email protected]> wrote: Hello experts, I have legacy
forward proxy used in enterprise network facing to internet behind firewall.
Unfortunately it cannot do partial object caching. I am looking if I can get an
alternate proxy to do this. My requirement is: 1. Partial object caching
so updates by apple etc. can be cached. Also video caching will just work. 2.
Streaming to multiple client at same time should be possible from single
server connection. It seems varnish can do above stuff. But it works
effectively as reverse proxy, so I have to position it before my proxy, as it
cannot work as upstream proxy directly. Also its cache seems gets vanished
after restart(Everything in cache is from heap). Do you guys know if ATS can do
this functionality? I believe it is not possible, but I thought just ask if we
achieve this by any means. A pointing to how to would be really appreciated.
Thank you from Newbie, Madhava
