Juliusz Chroboczek <Juliusz.Chroboczek@xxxxxxxxxxxxxx> wrote: > Michael Gersten: > > > getting keep-alive to work will help a lot with web browsing, > > Fabian Keil: > > > Is this an assumption or did you just forget to show your benchmarks > > to back this claim up? > > I've just tested this by running > > wget -p http://www.kde.org/screenshots/ No, you tested wget, which doesn't do parallel requests. The results are certainly interesting and may or may not show the difference between serialised requests that are done with and without keep-alive, but the numbers are worthless to make any assumptions about web browsing. Any modern browser I'm aware of uses multiple parallel connections if keep-alive isn't used, Firefox certainly does. > Please feel free to repeat my tests and report the results on this list. I have no reason to doubt your results, I just don't think they are relevant for web browsing. I just did some tests which I think are more meaningful. I used Firefox instead of wget, used the Fasterfox plug-in to time the requests and tried several proxy combinations. The versions were Tor 0.1.2.9-rc, Firefox 2.0.0.3, Polipo 0.9.99.1 and Privoxy's CVS version with some uncommitted modifications which should be irrelevant for this test. I didn't change my Privoxy configuration, which means there were several actions active, some of which effected the results. http://www.kde.org/screenshots/ contains no ads or tracking pixels, so filtering the page causes a delay without any gain. The test was done on a laptop with FreeBSD's powered(aemon) running. As a result the CPU frequency wasn't constant, but I doubt that it mattered for the end results. I first did five tests for every proxy combination, switching the proxy combination after each request. Requests where started with ctrl+F5 so Firefox didn't use its cache and additionally set the headers "Pragma: no-cache" and "Cache-Control: no-cache". I started Polipo with: polipo diskCacheRoot='' socksParentProxy=10.0.0.2:9050 and restarted it for every test. I kept Tor and Privoxy running all the time. Finally the numbers, the format is: |Proxy combination |results in the order I got them |average all |average without the best and worst result |average without the two worst results With http://www.kde.org/screenshots/: Firefox + Privoxy + Polipo + Tor: 40.950s, 6.100s, 6.294s, 24.290s, 56.680s 26.863s 23.845s 12.228 Firefox + Privoxy + Tor 59.523s, 7.493s, 6.822s, 156.438s, 35.282s 53.112s 34.099s 16.532 Firefox + Polipo + Tor 14.558s, 38.840s, 12.100s, 5.548s, 26.370s 19.483s 17.676s 10.735 I also tested with another website (http://www.spiegel.de/): Firefox + Privoxy + Polipo + Tor: 155.674s, 46.256s, 141.360, 47.120s, 35.967s 85,275s 78,245s 43,117s Firefox + Privoxy + Tor: 110.619s, 78.505s, 20.397s, 36.926s, 73,442s 63.983s 62,956s 43,588s Firefox + Polipo + Tor: 93.979s, 33.102s, 34.242s, 123.365s, 99.740s 76.886s 75.987s 53,774s Privoxy may have had a slight advantage here, because by removing three tracking pixels it had to do three requests less. However I think that it didn't matter much. The speed of the underlying Tor circuits seems to be the most important factor here and five samples probably aren't enough to prove anything. It certainly looks like keep-alive's effects aren't big enough to guarantee faster web browsing through Tor, though. Fabian
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