Re: [squid-users] refresh patterns!

On Mon, 13 Aug 2007, Adrian Chadd wrote:

> Yum!
>
> (Of course there's more to caching youtube - specifically, would need to
> implement a patch to squid to create a URI from that youtube URL which
> creates the same "host" part regardless of which bit of the CDN you fetch
> it from - using that URL for the cache storage and lookup. That'd be a
> pretty nifty start.)

Ok so you mean its not that its not caching flashmedia but the url of the
media file changes everytime you access it (request goes to different
servers for same content)..

1187069957.907 803 202.51.76.26 TCP_MISS/303 276 GET
http://youtube.com/get_video?video_id=69M_1ow_yEg&t=OEgsToPDskLjJ2R2yzfUrzuuPjSq4-2Z
1187069963.328 3857 202.51.76.26 TCP_MISS/302 181 GET
http://cache.googlevideo.com/get_video?video_id=69M_1ow_yEg
1187069973.085 1574 202.51.76.26 TCP_MISS/200 431 GET
http://video.google.com/s?ns=yt&sourceid=y&sdetail=p%3A%2F&vid=kPCRaxHXMKD2NSrRYUYeegC&docid=69M_1ow_yEg&el=detailpage&nbe=0&st=0.667&et=0.667&len=104&rt=14.7&fv=WIN%209%2C0%2C47%2C0

1187070090.365 1026 202.51.76.26 TCP_MISS/303 276 GET
http://youtube.com/get_video?video_id=69M_1ow_yEg&t=OEgsToPDskKQa32R7J750cPu_2LqiKdC
1187070091.880 1469 202.51.76.26 TCP_MISS/302 181 GET
http://cache.googlevideo.com/get_video?video_id=69M_1ow_yEg
1187070100.866 787 202.51.76.26 TCP_MISS/200 431 GET
http://video.google.com/s?ns=yt&sourceid=y&sdetail=p%3A%2F&vid=yCOz1cNdFnuPWJytHrikSgC&docid=69M_1ow_yEg&el=detailpage&nbe=0&st=0.733&et=0.733&len=104&rt=11.092&fv=WIN%209%2C0%2C47%2C0

Above is the request to same video twice. the part in the url "&t=.." in
youtube.com/get_video?.. and "&st=.." and "&et=.." and "&rt=.." in
video.google.com/s?.. keep changing with every request. but I do wonder
why the second url cache.googlevideo.com/get_video?.. got the miss.

anyways, we will not be caching any of these youtube
and googlevideo urls for now as we donot have much big cache space and
those flash videos would use up the cache space with minimal or none
chance of getting a hit, IMO. Please correct me if i'm wrong in this
assumption. But I'm very interested in caching these urls if someone could
pull off a patch as adrian suggested (maybe rip off those above tags from
the url while storing and looking up off the cache store). I'll be
increasing the storage space in the near future so it would be great to
see such a patch.. ;)

cheers.

Manoj

> > relevant bits in my Squid config:
>
> # Cache dynamic content from youtube/etc
> # Let the clients favourite video site through
> acl youtube dstdomain .youtube.com
> cache allow youtube
>
> # NOW stop any other dynamic stuff being cached
> acl QUERY urlpath_regex cgi-bin \?
> cache deny QUERY
>
> refresh_pattern -i \.flv$ 10080 90% 999999 reload-into-ims
>
> maximum_object_size 32 MB
> maximum_object_size_in_memory 512 KB
>
> So, who wants a t-shirt for implementing the above patch and demonstrating
> it works with Youtube? I just don't have the time.
>
>
>
> Adrian
>
>

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