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Some servers will reply like this, trying to avoid caching at any cost (I think): HTTP/1.1 200 OK Then our squid will create a vary object with all that information, giving this bomb: httpMakeVaryMark: accept="image%2Fpng,image%2F*%3Bq%3D0.8,*%2F*%3Bq%3D0.5", if-none-match="%225756ad27-47e%22", if-modified-since, accept-language="en-US,en%3Bq%3D0.8,pt-BR%3Bq%3D0.5,pt%3Bq%3D0.3", accept-encoding="none", x-client-locale, user-agent="Mozilla%2F5.0%20(Windows%20NT%2010.0%3B%20WOW64%3B%20rv%3A46.0)%20Gecko%2F20100101%20Firefox%2F46.0", x-device It's squid "fault" to convert spaces and symbols to %values, and I think no sanity check is performed on it.. still, I don't see the code where it checks if all this info from the new client is identical to the stored one.. and I don't know where the "loop" comes from... Now I think I'm confused... lol
-- Best Regards, Heiler Bemerguy Network Manager - CINBESA 55 91 98151-4894/3184-1751 Em 07/06/2016 08:59, Yuri Voinov
escreveu:
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 I want to give one example on the topic. Here is from one of my cache: /data/cache/d2/00/02/000004C3 0 102502 http://www.openoffice.org/favicon.ico /data/cache/d2/00/01/0000031D 0 161421 http://rgho.st.squidinternal/favicon.ico /data/cache/d1/00/2E/00005C04 0 33274 http://www.tcpiputils.com/favicon.ico Just take a look on file sizes. This is only favicon. 100 kbytes for favicon only! (on Microsoft I've seen 470 kbytes favicon once upon time). When we take a look into access.log, we often see several URL's for favicon: http://www.somesite.com/favicon.ico?v=1.44&id=41324134abcd123123123 Good site, isn't it? Loading 100 kbytes every time every client surf any site page. When I was doing research, it became clear that, in most cases, these same favicon were one and the same content. As an example, a client with a smartphone like to download 100 kB - and this is only a small portion of the page! - everytime? 100 kb of mobile data traffic in most countries of the world - decent money. Yes, usually from the client browser cache. What about the number of clients and the access point, which pays terabytes non-peering traffic? The same tricks I've seen with a user-agent. With Vary. 07.06.2016 16:36, Amos Jeffries пишет:On 7/06/2016 8:48 p.m., Yuri Voinov wrote:07.06.2016 4:57, Amos Jeffries пишет:On 7/06/2016 5:55 a.m., Yuri Voinov wrote:So. Squid DOES NOT and DON'T BE support gzip. The only way to do it - use ecap + desupported ecap gzip adapter. Let's accept this. We can support gzip. With restrictions. Ok. any other compression - false. No. No way. Get out. and so on. identity - this is uncompressed type. That's all, folks. Finally. As Joe does, we can remain only gzip and identity in Accept-Encoding and truncate all remaining.Locking the entire Internet to using your personal choice of gzip compression or none.gzip is the slowest and more resource hungry type of compression there is. deflate is actually faster for clients and just as widely supported.Unfortunately, Amos, no one has written any other compression algorithms support module. We have to eat what they give.Like I said deflate is widely available. Heiler's recent info shows that lzma is becomming more visible on the public web, which should help fix the one issue deflate has. And noone appears to be fixing the remaining issues in the Squid gzip eCAP module. There also seems to be a big push back from browser and some server vendors about compression in general. We had a fairly major fight in IETF to get HTTP/2 to contain data compression at all. It is still only in there as an optional extension that some are openly refusing to implement.Without any problem. Moreover, this type of can be push to all brunches of squid without any problem, because of this dramatically increases byte HIT.Responding with a single object to all requests makes your HIT ratio 100% guaranteed. The clients wont like you though if all they ever see is the same cat picture.It sounds ridiculous when put that way, but that is what these patches are doing for a unknown number of those "gained" HITs. See my previous post about how none of these patches are changing the request the server gets.But no one asked the question - why Squid in production installations has such a low hit ratioYes that has been asked, even investigated. The reason(s) are many complex details and small issues adding together to a big loss. They range from protocol things like Vary not being fine-grained enough (Key header being developed fixes that), through to client behaviour (Chrome sdch doubles the variant count - almost halving useful cache space), to server behaviour (Apache changing Vary header). What your testing of joes patches is showing is that the sdch effect Chrome has is probably way bigger than one would expect to be reasonable.that raises the question of expediency of application caching proxy. We do believe that this is a caching proxy?You are once again sweeping asside the critical requirement of content integrity to achieve high HIT ratio. Which is not something that I can accept into Squid as a default action.I continue to believe that 20% is unacceptably low cache hit ratio, given the very aggressive settings and the active use of Store ID. Which brings us back to the idea of the feasibility of using the SQUID as awhole.That kind of "unacceptable" statement simply cannot be made about cache HIT ratio. It is what it is. One cannot change the speed of light because it takes unacceptable long to travel through space. Two properly working caches in serial will have extremely different caching ratios. The one with most direct client connections trends towards 50-100% and the upstream one towards the servers will trend towards zero. The total cacheable ratio is unchanged, but each cache sees a different proportion of it and so shows different HIT ratios relative to their clients portion. Also, don't forget that browser cache disk space available are increasingly large as well. So their caches are growing in size and taking up a larger share of the total achievable HIT ratios in recentyears.Amos _______________________________________________ squid-users mailing list squid-users@xxxxxxxxxxxxxxxxxxxxx http://lists.squid-cache.org/listinfo/squid-users-----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJXVrctAAoJENNXIZxhPexGl8gIALRSaB3nC6fUjKM8GGL+ep3m NZganwbvtkLLLDHQFuTA3K9gvl/GWieQ/3jj+Pp45kgNIeVNsbwYF6IANOT1/olc XIGpHK0LICSeTA5kpSHU6hkdfao6AWSUFLci5WXl/Ay7qvzWI4h/NqPhyhoaJUSq LTmOePc98oALu4oZpmdmKy1D5yduLmjDy8cbIJTRc/SVha5tt4Sre7z8dI9geX9L PlrXBxbtH+oGAYu5qiuifQR9UZCoYL0wL30KzWLyIqmZJdT/NIshIRA1wHVdy9lL d0CNwheIPTvstnx8uKOMk4vN/Z5y+A6LnTHHoJgfRCyNwD1IayoPRY1CJffWVRk= =40f2 -----END PGP SIGNATURE----- |
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