Couldn’t get xperf to run, so I googled the error message.

That article told me what the problem was (I was running ProcExp at the same time, a no-no). It also described my problem (sort of, there was no indication that my CPU core was maxed out at the time), but it referenced a KB.

The easiest thing for me in the KB was to go to the advanced properties of my ethernet adapter, and turn off the LMHOSTS check mark.

Haven’t had the problem since!

I’ve stripped out every extension, run in safe mode, it still happens.

And while it’s been mostly affecting FF, it’s also been affecting Chrome, Digsby, and even Explorer and my text editor Uedit32. My install is about two years old, so I’m thinking about blowing the whole C: partition away and starting from scratch again.

This is the only hit when I search for “resmon” “waiting to finish network I/O”

Compared latest builds with the 32 bit version, the 64 version starts 1-2 sec faster at cold start, 0,5-1 sec faster at warm start.
The network I/O thread (as I wrote abound before, is still there.
Generally it feels a little bit snappier when browsing, but benchmarks are approx 10% worse than the 32- bit version (which I think is normal).

I can improve the coldstart a nice bit from approx 12-15 sec to 6-8 sec by change my default homepage from http://www.google.se to the preinstalled (?) by Firefox about:home.
I find that odd… but this is the only thing I have found reduce the cold start.

Nevertheless, there is an odd thing at my computer……

If I use the ResMon I can when I right-click at firefox.exe, and “analyse process”, I get following comment:
“One or more threads of firefox.exe is waiting to finish network I/O”
Underneath in the box says; “firefox.exe (Processor-ID: 3064) Thread: 3332″
(the numbers above are always random, if I check next time, there is some other numbers)

Have tried to google what that mean, but did not found any answer.

Only Firefox have this comment, no other process. If I run other browsers, they doesn’t neither have this comment.
My network and drivers, etc seams to be correct installed.

Except the slow load time, FF is acting normal.
It’s perceived snappy as IE9 or Chrome.
Also at benchmarks I get nice results.
I e Sunspider 0.9 = 220 ms (compared with Chrome 200), etc – completely normal.

But the slow startup does nagging me…..

I can if of interest post printscreens, etc if you tell me what kind of information you would like to investigate.

Rgds

My name is “Taras”. This is a good tip, but there is something seriously wrong with your setup. Your 2-3second warm startup is about 4-6times slower than it should be. Addon compatibility reporter thing doesn’t actually test startup performance, so it’s probably some addon causing super-slow startup speed.

However, have tried all kinds of tips and tricks I found and still found Firefox to be extremely slow on start up.
I have a normal cold start of around 15 sec (min 10 sec, max 19 sec).
I have only 5 addons, and 4 GM scripts.
They are all approved by “Add-on Compatibility Reporter 0.7″

Here is what I found what speed up at least on my computer:

Tip no 1:
I normally use http://www.google.se as my homepage, having that a cold stat takes approx. 15 sec.
If I choose to have Minefield’s start page (about:home) as my homepage I can reduce the cold start to 6-7 sec
Don’t ask me why – it just reduce the load time with more than half…

Tip no 2:
And here’s the big win, if I do like this below I have a COLD START OF ONLY 2-3 SECONDS.

1. Create a shortcut of the Firefox icon, it’s OK to change the name such as “Firefox prestart”.
2. Select the shortcut icon, right-click, choose properties, find the box target (where you probably read this: “C:\Program Files (x86)\Firefox\ firefox.exe”)
3. Add the following parameter -silent afterwards, do not forget a space after the quotation mark. Ie “C:\Program Files (x86)\Firefox\firefox.exe” -silent
4. Click OK to save the change.
5. Then drag the icon to the Autostart folder (see “All Programs”, “Start Button”) and drop the icon there.
6. Restart the computer.

Now, Firefox will be loaded when Windows starts up. But after being “booted” minimized, Firefox will be closed down again and do not stay in memory.
That process adds approx. 2 sec to your total windows boot time. But as a normal Win boot takes 50-55 sec at my computer, it’s barely notable.

The result is that you can “cold start” Firefox as if it were a “Warm start”.
And this without using other programs.

On my computer, I can now cold start Firefox in 2-3 seconds, not bad compared to before 10-18 seconds …..
Do you have an SSD, Firefox will probably start more or less instantly ….

Check it out

And Tara, if you find my suggestions of any interest, please forward it to Mozilla’s developers for further investigation.

After reading these pages:
http://www.gettingclever.com/2008/06/vacuum-your-firefox-3.html
http://www.downloadsquad.com/2009/08/24/speed-up-firefox-by-cleaning-out-your-sqlite-databases/
https://developer.mozilla.org/en/Storage/Performance#Vacuuming_and_zero-fill
https://addons.mozilla.org/en-US/firefox/addon/11198/
https://addons.mozilla.org/en-US/firefox/addon/13824/
https://addons.mozilla.org/en-US/firefox/addon/13878/
http://www.sqlite.org/lang_vacuum.html

The fragmentation of the SQLite database seems to be a significant factor of slowness.

Keeping browsing history causes a constant ratio of inserts and deletes. Eventually this may lead to a total fragmentation of that database.

On the other hand, Firefox keeps 90 days of browsing history by default. And average users don’t tweak their preferences almost at all.

As a result, average users end having 90 days of totally fragmented browsing history in their disks.

Loading that on start-up is painfully slow.

And that is what Firefox does.

In one sentence, assessing all the above as true enough, it is probable that the average user is experiencing very slow cold start-ups mainly due to Firefox loading a significantly large, very fragmented, SQLite database.

Two complementary things can be made to avoid this scenario:
1.- Don’t load that database on start-up. Or only the 10% of that data that is useful for 90% of the cases. The rest should be loaded only later.
2.- Run database defragmentation automatically periodically. For example when inactivity is detected.
Design details can be further discussed for both solutions.

Yeah, I’ve noticed more responsiveness in Firefox 4 beta 1 and I appreciate it greatly.

Also I’ve noticed beta 1 being super-stable. I installed it the day after release and so far it has not crashed. No once. I mean with my profile, my add-ons (6 yet enabled), and my 6 to 8 hours of use per day.

I’m sure all together is not a coincidence. So congratulations on the good work.