In reply to a post by RobertoS:

?
Surely unless his browsing habits have changed dramatically in the last two weeks that would have always been the case?

Sorry I havent replied yet, but this person has my exact thoughts on the matter.

A couple of weeks ago I was on 2 meg broadband with Sky and I never experienced this problem of switching between tabs and taking ages for it to load etc.

My setup has not changed at all, apart from the installation of Infinity


HOWEVER, I have switched to Chrome and yesterday I didnt experience the problem......

In reply to a post by Anonymous:

In reply to a post by RobertoS:

?
Surely unless his browsing habits have changed dramatically in the last two weeks that would have always been the case?

Sorry I havent replied yet, but this person has my exact thoughts on the matter.

A couple of weeks ago I was on 2 meg broadband with Sky and I never experienced this problem of switching between tabs and taking ages for it to load etc.

My setup has not changed at all, apart from the installation of Infinity


HOWEVER, I have switched to Chrome and yesterday I didnt experience the problem......

Have you flushed the DNS cache on your PC and IE?

Edited by deleted (Fri 24-Jun-11 21:39:30)

In reply to a post by RobertoS:

I too thought I was being polite, apart from my initial objection to being treated as though I have no knowledge of how computers work at this level.

I see you don't refute any of my post, much of which pulls holes in your explanation.

I'll address them. I was at work and unfortunately didn't have time to make an extended reply.

Second, if a modern OS uses time-slicing to apportion time between threads then an awful lot of CPU time is going begging and there is a lot of inefficiency while threads wait for their next slice.

This is incorrect. It is the most efficient method of providing fair concurrent execution of the many threads in an OS (excluding certain specific real-time critical systems)[6].

If you read any book on Operating Systems[5], or read documentation on OS Schedulers (Linux[1], UNIX, ...), they use pre-emptive multi-tasking [1] (where time-slicing is used in the general sense to mean thread scheduling to apportion CPU time for many threads to execute, rather than any specific TS algorithm) .

For instance, Linux scheduling is implemented with extremely efficient algorithms[2][3] that also account for priority and other weighting factors to determine how much of the processing resources are given to any particular processor[4], and without it there is no way for the hundreds of threads to progress concurrently in an practicable manner.

[1] http://oreilly.com/catalog/linuxkernel/chapter/ch10.... (these are older than the CFS algorithm, but still used in many distros)
[2] http://doc.opensuse.org/products/draft/SLES/SLES-tun...
[3] http://en.wikipedia.org/wiki/Completely_Fair_Scheduler
[4] https://gustavus.edu/+max/os-book/updates/CFS.html
[5] Andrew Tanenbaum's Operating Systems book is a bible, great stuff. Highly recommend it for the intrepid computing scientist.
[6] http://en.wikipedia.org/wiki/Scheduling_%28computing%29

Third, I'd be very surprised if the OS is telling the processor which core to use for any given thread.

When a de-scheduled (or new) thread reaches the moment that it must be scheduled to run, the OS will decide which processor (or core) to dispatch the thread to. The given thread's state to will be set in that processor, and execution is resumed (i.e. it must ensure that the register values are correct for the given thread, and it transparently continues executing as if it had never been de-scheduled). For very specific use-cases certain programs may have a processor affinity set, but this is rare as it is usually more efficient to let the OS decide, and spread the load dynamically.

OS scheduling algorithms are intelligent enough to schedule threads wherever the most resources are available.

There are plenty of exceptions for edge-case usage, I don't want to bore people with it here by writing a huge amount, but there are reams of resources on the Internet for those who are interested .

Whilst the browser as a whole will use multi-threading, the tabbed view implementation may for some reason not do so.

It is almost certain that it would have to (use threads, or an equivalent concurrent mechanism), otherwise the stuff rendered in the content pane would freeze as you interacted with the tab. Most of those threads will do very little taxing work however.

hth

edit: missed a point that needed a response

Edited by deleted (Sat 25-Jun-11 03:01:49)

In reply to a post by Anonymous:

Hi All

I had BT Infinity installed a couple weeks ago and synched at 30 meg. The problem is, whenever I am browsing my internet explorer cannot keep up!

When i download a file everything is great. However browsing the internet is a problem, going between tabs takes a few seconds all the time, as if its waiting for one of the pages to load.

Anyone had a problem with this? (First person who blames it on IE will be ignored)

I meant to add this link in my post to you the other day :

http://acid3.acidtests.org/

it will give you some indication on how your browser is performing and also how any other ones that you try perform.


i get :

100/100 for opera
97/100 for safari and
96/100 for firefox

though tbh i dont use firefox that often i dont really like it.

as far as chrome and IE go i simply dont use them.....


hope this helps..

Acidtests gives me:

IE 9 - 95; Firefox 5 - 97: Chrome 12 - 100

In reply to a post by dustofnations:

In reply to a post by Chrysalis:

In reply to a post by Anonymous:

Hi All

I had BT Infinity installed a couple weeks ago and synched at 30 meg. The problem is, whenever I am browsing my internet explorer cannot keep up!

When i download a file everything is great. However browsing the internet is a problem, going between tabs takes a few seconds all the time, as if its waiting for one of the pages to load.

Anyone had a problem with this? (First person who blames it on IE will be ignored)

funny enough yes.

no browsers yet can spread cpu load in a single tab across multiple cpu's, eg. on my 4 core machine I regurly see browsers hit 25% cpu usage when loading pages which is basically maxing out. Basically meaning my web sites are now been saturated by cpu power rather than bandwidth now. Of course not every site does it, but many do.

You have threads and processes confused. All modern browsers use many threads per tab (drawing the UI, making multiple simultaneous HTTP requests while still allowing you to use the UI, ...). Threads will not show up in your process list as separate entities.

maybe but it still isnt multi core, I cannot make 'any' modern web browser use more than one cpu core on any web page. So if a web browser is using 25% on a quad core then its maxed out. Just having the OS been multi cpu compatible does not automatically make every app that runs on it the same.

Edited by Chrysalis (Mon 27-Jun-11 09:23:46)