Has anyone else noticed that looking over element timings in the Net panel of
Firebug, nothing seems to be less than 15ms?  Seems as if there is something
limiting the precision of timings we can glean here. Anybody know what's going
on or discovered a way around that?

Call me paranoid, but a large number of little numbers being off by a little bit
can add up to bigger mischief, no?

/dtk

Thanks, I took a closer look with the httpfox and found that the files are
cached via the if-modified option. So a request still goes to the server to ask
whether anything has changed, if not, usually the case everything comes out of
the cache.

Seems like a good compromise for a frequently changing site?



--- In exceptional-performance@yahoogroups.com, Antonia Kwok <antoniakwok@...>
wrote:
>
> Elyrion,
>
> How far in future are you setting the expires header?
> YSlow will give warning for components with expiration less than 2 days.
>
> With a longer expiration, the cached copy will stay fresh longer, which means
> browser can serve this cached copy without contacting the server at all.
> If the cached copy is stale, browser will need to send a conditional get to
the
> server.  YSlow and Page Speed are probably suggesting you to look into this
> scenario.
>
>
>
>
>
> ________________________________
> From: Elyrion <Elyrion@...>
> To: exceptional-performance@yahoogroups.com
> Sent: Wed, August 11, 2010 7:35:55 AM
> Subject: [exceptional-performance] Caching
>
>
> Yslow and pagespeed suggest caching, that is to add expire headers tot he
> resources. But when I look at the page most resources are loaded from the
cache
> and in the statistics department it notes that the only thing reloaded is the
> html, every thing else comes from the cache.
>
> So why does it tell me to take a closer look to caching?
>

Thanks Rob, but it's not JavaScript time I'm worried about.

My focus is on network time to download page elements.  Wondering if anyone has
gotten deep into the weeds of the net timings coming back from Firefox
(displayed in Firebug or elsewhere)?

/dtk

--- In exceptional-performance@yahoogroups.com, "Rob Larsen" <Rob@...> wrote:
>
> You may want to check this article, which gives insight on why the bottom
> limit is 15ms:
>
>
>
> http://ejohn.org/blog/accuracy-of-javascript-time/
>
>
>
> (basically anything lower gets rounded down)
>
>
>
> Rob Larsen
>
>  <http://www.drunkenfist.com/> DrunkenFist.com
>
>  <http://htmlcssjavascript.com/> HTML + CSS + JavaScript
>
>
>
>
>
>
>
> --- In exceptional-performance@yahoogroups.com, "smto_dtk" <dave@> wrote:
>
> >
>
> > Has anyone else noticed that looking over element timings in the Net panel
> of Firebug, nothing seems to be less than 15ms?  Seems as if there is
> something limiting the precision of timings we can glean here. Anybody know
> what's going on or discovered a way around that?
>
> >
>
> > Call me paranoid, but a large number of little numbers being off by a
> little bit can add up to bigger mischief, no?
>
> >
>
> > /dtk
>
> >
>

I'm assuming that you don't mean a local devbuild - apologies if you do.  (If so
then please ignore what follows.)

Maybe I'm over cautious but I do this from time to time in batch locally and
then check in the new images.  I've had a few pngs go funny (especially on
mobile phones) so prefer to do it locally and then eyeball.  (I use
http://www.jonof.id.au/forum/index.php?topic=846.45 and one of the tools in the
suite - I forget which - makes a bug in some versions of zlib on phones munge
the images.)

BTW: on windows, optipng (is it x-platform?  I forget) regularly kills my
machine, but this is no bother as I run this batch over my lunch break.  (This
has happened on 3 machines.)  I wouldn't therefore run it on my build machine.

(Does this help one iota?)  Hope so.

Neil

Thanks,

Specifically, it's for:

http://github.com/paulirish/html5-boilerplate/issues#issue/16

So, how/where it will be used is for a lot of different people to decide.
That said, I can't imagine doing this for local builds. It really should
be a production/build kit/final step kind of thing.

I'm basically just looking to have the task available for when people need
it.

Thanks for the link. I'll check it out.

Rob


> I'm assuming that you don't mean a local devbuild - apologies if you do.
> (If so then please ignore what follows.)
>
> Maybe I'm over cautious but I do this from time to time in batch locally
> and then check in the new images.  I've had a few pngs go funny
> (especially on mobile phones) so prefer to do it locally and then eyeball.
>  (I use http://www.jonof.id.au/forum/index.php?topic=846.45 and one of the
> tools in the suite - I forget which - makes a bug in some versions of zlib
> on phones munge the images.)
>
> BTW: on windows, optipng (is it x-platform?  I forget) regularly kills my
> machine, but this is no bother as I run this batch over my lunch break.
> (This has happened on 3 machines.)  I wouldn't therefore run it on my
> build machine.
>
> (Does this help one iota?)  Hope so.
>
> Neil
>
>

Hi,

I've installed new FireBug version 1.6b1.
After this, every page loading ends with message box "TypeError: yscontext is
undefined".

This happens only with 1.6b1 + YSlow.
Previous alpha versions worked correctly.

---
wbr, Serge Travin.

Hi,

I had never tried this before, when I ran it on a website, it reported an error
status for over half the images:

Error writing the optimized file

Is this normal behaviour? Or am I doing something wrong here?

Thanks!

I have been using Smush.it and a few other lossless compression approaches and
wanted to survey experiences with lossy algorithms.

To be frank, some images have relatively little size improvement with lossless,
making it little worth the effort.  However, in a few cases I have just used
iPhoto to test a lossy compression and have gotten 90-95% improvements with
little apparent degradation.

Are there others here who have experimented with this?  Are their algorithms or
libraries that are better or worse?  Could you recommend a target quality that
would be generally applicable?

Thanks,
Matt

--- In exceptional-performance@yahoogroups.com, "daveartz" <daveartz@...> wrote:
>
> Stoyan/Pat, you guys forgot caching :)  Probably the single biggest thing I'm
trying to get folks at AOL to do, with the single biggest ROI (on repeat view). 
And Pat don't say you covered this in "Reduce HTTP Requests" :P
>
> (and that's why I don't like that rule, too vague, might as well say Reduce KB
and be done with our 2 rules :)
>
> Stoyan - Why stop at "lossless" image compression? "Lossy" image compression
is a big issue for us.  Check out this baby from AOL Shopping:
>
>
http://ah.pricegrabber.com/product_image.php?masterid=37223072&width=400&height=\
400
>
> Coming from a feed in the PNG format (134K), should be JPEG (18K).
>
> An optimizer's work is never done...
>
> While I think Pat & Stoyan's are all must-do's from my perspective, allow me
to play devil's advocate on why it's good to at least be aware of the others.
>
> In one recent case, jQuery selectors slowed down a particular site by 20% and
another by 10%.  Thus, rules were born:
http://www.artzstudio.com/2009/04/jquery-performance-rules/
>
> Another example would be stripping comments/obfuscating JS. Depending on how
happy the developer is to comment their code, this can be a big issue and large
% of weight/time.
>
> I agree that too many rules may have diminishing returns, but depending on the
site (I should say developer or designer), one of those rules we leave off our
checks could actually sting the most and potentially be a big source of the
problem.
>
> So I'd be sure to include rules that have historically caused at least a 10%
load time penalty in whatever "list" is created.
>
> Dave
>

Only to say that jpegtran can sometimes squeeze an extra handful of percent of
lossless compression.  Not really what you were asking I know, but I mention it
because AFAIK it's 'safe' so it can be a transparent task on the build server. 
(I'm sure that this is one of the 'other' tools you mention and that you've
already tried it.)

If you crack the generally applicable part below, I for one would love to know,
please.  :-)  BTW: are you talking PC only or hand-held as well?  I've found I
can get away with dreadful images on those small, low-res screens which is, of
course, a win over the wire and also a win in local resources used.  But again,
this has always involved people actually looking at images.

Neil

P.S.  Do you crush gifs - if you have any kicking around your site that is. 
I've noticed editors put in huge headers which say little more than 'I was
created using...'.  As gifs are often small the proportional weight can be high
- often enough to force a second roundtrip.  Easily removed using a text editor
or something like http://chemware.co.nz/tgo.htm



--- In exceptional-performance@yahoogroups.com, Sergey Chernyshev
<sergey.chernyshev@...> wrote:
>
> The trick here is how to measure when to stop without involving a user...
>
> As for the general jpeg quality, it's definitely part of image
> post-processing that needs to happen in editorial or design teams. It is not
> that easy to enforce though...
>
>          Sergey
>
>
> On Tue, Aug 31, 2010 at 3:41 PM, Matthew <mattroche@...> wrote:
>
> >
> >
> > I have been using Smush.it and a few other lossless compression approaches
> > and wanted to survey experiences with lossy algorithms.
> >
> > To be frank, some images have relatively little size improvement with
> > lossless, making it little worth the effort. However, in a few cases I have
> > just used iPhoto to test a lossy compression and have gotten 90-95%
> > improvements with little apparent degradation.
> >
> > Are there others here who have experimented with this? Are their algorithms
> > or libraries that are better or worse? Could you recommend a target quality
> > that would be generally applicable?
> >
> > Thanks,
> > Matt
> >
> > --- In
exceptional-performance@yahoogroups.com<exceptional-performance%40yahoogroups.co\
m>,
> > "daveartz" <daveartz@> wrote:
> > >
> > > Stoyan/Pat, you guys forgot caching :) Probably the single biggest thing
> > I'm trying to get folks at AOL to do, with the single biggest ROI (on repeat
> > view). And Pat don't say you covered this in "Reduce HTTP Requests" :P
> > >
> > > (and that's why I don't like that rule, too vague, might as well say
> > Reduce KB and be done with our 2 rules :)
> > >
> > > Stoyan - Why stop at "lossless" image compression? "Lossy" image
> > compression is a big issue for us. Check out this baby from AOL Shopping:
> > >
> > >
> >
http://ah.pricegrabber.com/product_image.php?masterid=37223072&width=400&height=\
400
> > >
> > > Coming from a feed in the PNG format (134K), should be JPEG (18K).
> > >
> > > An optimizer's work is never done...
> > >
> > > While I think Pat & Stoyan's are all must-do's from my perspective, allow
> > me to play devil's advocate on why it's good to at least be aware of the
> > others.
> > >
> > > In one recent case, jQuery selectors slowed down a particular site by 20%
> > and another by 10%. Thus, rules were born:
> > http://www.artzstudio.com/2009/04/jquery-performance-rules/
> > >
> > > Another example would be stripping comments/obfuscating JS. Depending on
> > how happy the developer is to comment their code, this can be a big issue
> > and large % of weight/time.
> > >
> > > I agree that too many rules may have diminishing returns, but depending
> > on the site (I should say developer or designer), one of those rules we
> > leave off our checks could actually sting the most and potentially be a big
> > source of the problem.
> > >
> > > So I'd be sure to include rules that have historically caused at least a
> > 10% load time penalty in whatever "list" is created.
> > >
> > > Dave
> > >
> >
> >
> >
>

Hi, I want to generate links to Smushit so that visitors can optimize images
online.  I can very much understand if you don't want allow links that trigger
immediate optimization (although that also would be great), however it would be
very nice if you can at least allow links that fill in the textarea with default
URLs, so that the visitors can then complete the process by clicking on the
"Smush" button.

For example the URLs might look something like this:
http://www.smushit.com/?url-list=http%3A%2F%2Fexample.com%2Fabc.jpg,http%3A%2F%2\
Fexample.com%2Fxyz.jpg

Best Regards
N.E.

 

Hi, I want to generate links to Smushit so that visitors can optimize images online. I can very much understand if you don't want allow links that trigger immediate optimization (although that also would be great), however it would be very nice if you can at least allow links that fill in the textarea with default URLs, so that the visitors can then complete the process by clicking on the "Smush" button.

For example the URLs might look something like this: http://www.smushit.com/?url-list=http%3A%2F%2Fexample.com%2Fabc.jpg,http%3A%2F%2Fexample.com%2Fxyz.jpg

Best Regards
N.E.

Thanks for your response Antonia.

I don't use yslow. Could you kindly give me a URL for Smushit that is an example
of how to achieve my goal?

Thanks,
N.E.

--- In exceptional-performance@yahoogroups.com, Antonia Kwok <antoniakwok@...>
wrote:
>
> The second part of your request is already supported by smushit. It is how
yslow passes the list of images to be optimized.
>
> Sent from my iPhone
>
> On Sep 4, 2010, at 10:40 AM, "nebloke" <nebloke@...> wrote:
>
> > Hi, I want to generate links to Smushit so that visitors can optimize images
online. I can very much understand if you don't want allow links that trigger
immediate optimization (although that also would be great), however it would be
very nice if you can at least allow links that fill in the textarea with default
URLs, so that the visitors can then complete the process by clicking on the
"Smush" button.
> >
> > For example the URLs might look something like this:
http://www.smushit.com/?url-list=http%3A%2F%2Fexample.com%2Fabc.jpg,http%3A%2F%2\
Fexample.com%2Fxyz.jpg
> >
> > Best Regards
> > N.E.
> >
> >
>

Hello?  Hellooooo?  Is this thing on?

If anyone is out there... Are there any people from Yahoo or any developers for
Smushit actually in this group, or do I need to go barking up some other tree?

--- In exceptional-performance@yahoogroups.com, "nebloke" <nebloke@...> wrote:
>
>
> Thanks for your response Antonia.
>
> I don't use yslow. Could you kindly give me a URL for Smushit that is an
example of how to achieve my goal?
>
> Thanks,
> N.E.
>
> --- In exceptional-performance@yahoogroups.com, Antonia Kwok <antoniakwok@>
wrote:
> >
> > The second part of your request is already supported by smushit. It is how
yslow passes the list of images to be optimized.
> >
> > Sent from my iPhone
> >
> > On Sep 4, 2010, at 10:40 AM, "nebloke" <nebloke@> wrote:
> >
> > > Hi, I want to generate links to Smushit so that visitors can optimize
images online. I can very much understand if you don't want allow links that
trigger immediate optimization (although that also would be great), however it
would be very nice if you can at least allow links that fill in the textarea
with default URLs, so that the visitors can then complete the process by
clicking on the "Smush" button.
> > >
> > > For example the URLs might look something like this:
http://www.smushit.com/?url-list=http%3A%2F%2Fexample.com%2Fabc.jpg,http%3A%2F%2\
Fexample.com%2Fxyz.jpg
> > >
> > > Best Regards
> > > N.E.
> > >
> > >
> >
>

In the spirit of "teaching a man to fish"...

(1) install the free version of HTTPWatch (http://www.httpwatch.com/download/)

(2) Install ySlow

(3) Analyze a page with ySlow

(4) Start HTTPWatch recording

(5) Click on the SmushIt link next to an image

(6) Stop HTTPWatch recording and find the request to SmushIt.

What you find is something like this -

http://www.smushit.com/ysmush.it//ws.php?img=http://www.siteconfidence.com/image\
s/videoTitleStatic.jpg

And you get an application/json response

{"src":"http:\/\/img-cdn.mediaplex.com\/0\/7778\/42351\/AGv3-banner-prospect.jpg\
","src_size":69968,"dest":"http:\/\/smushit.zenfs.com\/results\/b552f8a5\/smush\\
/%2F0%2F7778%2F42351%2FAGv3-banner-prospect.jpg","dest_size":68277,"percent":"2.\
42","id":""}

Src = the source image URL

Src_size = original image byres

Dest = link to optimised image

Dest_size = site of optimised image

Percent = percentage saving

Id= some sort of tag, dunno what.

But since Antonia kindly replied you can use the POST method in her reply as
opposed to the GET via the URL above if you want. The POST method sounds like it
can accept a list of images which is good.

cheers,
Steve


--- In exceptional-performance@yahoogroups.com, Barry Hunter <barry@...> wrote:
>
> Err, you could just install YSlow, and observer what it does?
>
> On 8 September 2010 13:58, nebloke <nebloke@...> wrote:
>
> >
> >
> >
> > Hello? Hellooooo? Is this thing on?
> >
> > If anyone is out there... Are there any people from Yahoo or any developers
> > for Smushit actually in this group, or do I need to go barking up some other
> > tree?
> >
> >
> > --- In
exceptional-performance@yahoogroups.com<exceptional-performance%40yahoogroups.co\
m>,
> > "nebloke" <nebloke@> wrote:
> > >
> > >
> > > Thanks for your response Antonia.
> > >
> > > I don't use yslow. Could you kindly give me a URL for Smushit that is an
> > example of how to achieve my goal?
> > >
> > > Thanks,
> > > N.E.
> > >
> > > --- In
exceptional-performance@yahoogroups.com<exceptional-performance%40yahoogroups.co\
m>,
> > Antonia Kwok <antoniakwok@> wrote:
> > > >
> > > > The second part of your request is already supported by smushit. It is
> > how yslow passes the list of images to be optimized.
> > > >
> > > > Sent from my iPhone
> > > >
> > > > On Sep 4, 2010, at 10:40 AM, "nebloke" <nebloke@> wrote:
> > > >
> > > > > Hi, I want to generate links to Smushit so that visitors can optimize
> > images online. I can very much understand if you don't want allow links that
> > trigger immediate optimization (although that also would be great), however
> > it would be very nice if you can at least allow links that fill in the
> > textarea with default URLs, so that the visitors can then complete the
> > process by clicking on the "Smush" button.
> > > > >
> > > > > For example the URLs might look something like this:
> >
http://www.smushit.com/?url-list=http%3A%2F%2Fexample.com%2Fabc.jpg,http%3A%2F%2\
Fexample.com%2Fxyz.jpg
> > > > >
> > > > > Best Regards
> > > > > N.E.
> > > > >
> > > > >
> > > >
> > >
> >
> >
> >
>

Hi Antonia,

I did indeed miss that message. Your help is much appreciated!

You can see the links that I am able to now automatically generate, thanks to
your help, over at http://ImgOps.com/

( Although it doesn't work until you use the site together with an image URL. 
Here is an example: http://imgops.com/www.angrybearblog.com/cat.jpg )

Hopefully it will eventually lead a good deal more new website developers over
to Smushit and in turn to YSlow, and speed up more websites, and make the world
a better place, and solve global warming, and lead to world peace.

Best Regards,
N.E.

--- In exceptional-performance@yahoogroups.com, Antonia Kwok <antoniakwok@...>
wrote:
>
> I replied to you directly on Tuesday without posting to the group.  You may
have
> overlooked this in your mailbox.  Anyway, the URL and parameters are below.
> BTW, I am from Yahoo.
>
>
>
>
> ________________________________
> From: Antonia Kwok <antoniakwok@...>
> To: nebloke <nebloke@...>
> Sent: Tue, September 7, 2010 11:34:16 AM
> Subject: Re: [exceptional-performance] Re: Wish to link to Smushit with
> specified images for optimization
>
>
> Use POST to http://www.smushit.com/ysmush.it/
>
> In the post body, parameter name is "img", the value is the list of image url
> delimited by "\n".
>

Hi,

I've recently released a new YSlow extension - Web Metrics Framework. You can
install it from Mozilla Add-on gallery:
https://addons.mozilla.org/en-US/firefox/addon/221495/

It's a new ruleset for YSlow based on Google Web Metrics:
http://code.google.com/speed/articles/web-metrics.html

For more details, read my post:
http://www.javascriptrules.com/2010/08/25/web-metrics-framework/

The source code is in my GitHub:
http://github.com/marcelduran/Web-Metrics-Framework

Your feedback and comments are highly appreciated to help me improving this
extension.


Thanks,

Marcel

So I have tweaked my .htaccess file to include expires headers, however on my
home page I have an image slideshow that uses timthumb.php
http://www.darrenhoyt.com/2008/04/02/timthumb-php-script-released/ they format
like this  <img
src="/scripts/timthumb.php?src=/images/whatever.jpg&h=150&w=150&zc=1"> The
expires date on this seems to be the present... this is dynamic content so I
added the following code to .htaccess:

# Force no caching for dynamic files
<IfModule mod_headers.c>
<FilesMatch "\.(php)$">
   Header set Cache-Control "no-store, no-cache, must-revalidate, max-age=0"
   Header set Pragma "no-cache"
</FilesMatch>
</IfModule>

Yet YSlow is still picking up the timthumb.php files as being incorrect, how
come? is it not picking up Cache-Control or have I done something wrong?

Thank you

Will