[tor-talk] ads slow Tor Browser dramatically

[Joe Btfsplk]

On 11/4/2012 5:45 AM, andrew at torproject.is wrote:
> On Fri, Nov 02, 2012 at 01:06:50PM -0500, joebtfsplk at gmx.com wrote 1.3K bytes in 26 lines about:
> : TBB is already slow, which is understandable.  Using "stock" TBB
> : that allows ads & possibly other items increasing bandwidth is far
> : slower on many sites - even news sites - than same TBB version w/
> : just AdBlock Plus.
>
> Can you quantify this performance difference between TBB with ads and
> TBB without ads?
>
Sure, I could.  If a Tor dev w/ "the power to make changes" says 
blocking ads would definitely be considered, if data were provided 
showing increase in data downloaded & longer page load times. Otherwise, 
would be an exercise in futility.
Forget speed for now - the additional data load of all ads on the entire 
Tor network has to be large.  No tests needed to figure that out.  
Whether it's a good idea to block ALL ads is another subject.

Even in regular Fx, the difference is often many sec longer to load w/ 
all ads allowed.  Don't have to do scientific tests to know it's way 
slower.  But, for the times I had a status addon showing page load time, 
could be anywhere from 3 - 60 sec longer w/ all ads allowed, depending 
on the page & the actual content & # of ads.  Repeating the process many 
times on diff days / time, clearing caches between each reload gave a 
pretty decent avg, eliminating ISPs / servers being overloaded, etc.

Though not a valid, scientific test - loading Mozillazine Forums Index 
page in regular Fx (don't have a monitoring addon in TBB right now):
W/ AdBlock Plus:  81 KB loaded; 2.59 sec
W/O AdBlock Plus:  86 KB loaded; 3.96 sec
Again, consider the additional data load on ENTIRE Tor network.
The "w/ ads values" on given site will change, as the ads delivered 
change, by the min / hr / day.  Mozillazine isn't particularly 
overloaded w/ ads.  Time & data difference between ads / no ads can be 
negligible or dramatic, depending on the ads.

In TBB, the "proof" is in identical instances of TBB, except one had 
AdBlock Plus.  Again, I'd rather Tor project develop something on their 
own, or at least monitor / verify that any addon used is "safe," as they 
do w/ HTTPS Everywhere, NoScript.  Though I'm not sure how often & 
thoroughly Tor devs "test" an EXTREMELY complicated addon like NoScript 
- yet, they use it.  There's a reason an addon (_like_ AdBlock Plus) is 
most popular addon from MAO.

Pages in TBB can time out before loading, w/ all ads allowed, in 
addition to Tor network slowness.  Same pages w/ ads blocked usually 
load faster (if they have many ads).  How much faster depends on the 
site, # & type of ads, relays used in Tor network, etc.  Doing same 
general comparisons over weeks, months, gives a better representation.  
If ads significantly affect regular Fx, why would TBB be different?  If 
anything, ads might affect TBB more - mainly pages timing out & also 
making a slow network even slower.