We plan on developing a new product and Flex popped in my
mind as a development platform. I know a good deal of Flex 1.5, but
only used it for personal sites.
My question is how well Flex behaves in a large scale
environment to those who have deployed it in such. Server load will
be at least thousand / day.
Thanks!Flex deployed on a large scale?
Well, I'm about to find out! The only concerns I have are the
initial download, abilities of the client's computer, and my upload
bandwidth.
My initial download is ~2mb(i know its big, gotta reduce),
everything runs fine on my pcs/macs.. but they're new, and my
bandwidth is 1mbps up. I'm launching the site on March 1st, and
moving from 3rd party hosting to our own server (already done, just
gotta switch links). I get between 200-1600 loads per day.. average
is ~500. I'm looking forward to the launch, and I'll post more info
as I get it.
note: I've been having a ton of fun developing the site in
flex.. it's been a great learning experience.Flex deployed on a large scale?
Hey phi2265,
I'd like to check your site out when it's launched on Mar
1st. Would you mind posting the address for us to check it out.
Maybe your site give us some ideas for our own apps.
John
Yeah, no problem. I'm going to wait until then to post the
link however. I'm still finishing and testing.
Does anyone know of any other sites that use Flex or another
RIA? It seems to me like there aren't many out there yet... is the
concept just too new? I'm guessing things are still in development.
Its nice to be on the edge of things, but frustrating
sometimes.. I'm actually stuck on something right now, haha.
I have something in the works *grin*
Most are in development I believe. I have found that it takes
a little bit of resourcefulness to get going since Flex 2 has not
been out for *that* long. But I am a sponge for information so I
have no problem scouring the blogs, etc to figure out how to piece
my app together as a first crack at it.
Since languages like Java, C++, Perl, CF, ASP, PHP, have been
around for a while, the market seems to be saturated somewhat with
these skills. You have guys with 10+ years of C++, etc. It's a good
opportunity and time for us to put something together and I plan on
taking full advantage of it!
Just my two cents...
-Westside
Yeah I know what you mean. I've searched all over the web for
solutions sometimes.
Any sites that you frequent?
I joined the flex coders group on yahoo..
http://tech.groups.yahoo.com/group/flexcoders/
theres a ton of info there.
I've also found useful code on cflex.net
Hmm... I made one medium sized application in 1.5 (approx 10
screens, user access %26lt;1000 times per day) and it seems to be
working alright for the client.
Now I am working on a major application (over 20 main
screens, and definately access%26gt;1000 times per day) and it is not
going well. I am really worried about the bugs and memory issues of
Flex 2.0. I have also not found a sure-fire way to address these
potential issues. I can say this: for the size of application we
are making, Flex and Flash Player just aren't up to the job.
Compiled and executed as a single .swf application results in 755MB
ram usage and for some reason a constant CPU access of 60% (Pentium
4 proc.) after accessing every screen. And this is just FlashPlayer
doing what it is supposed to. Me, not being a computer engineer,
can't really address these problems. Flex and AS aren't C. I can't
control memory usage with my code. By breaking up the huge
application into smaller ones and then loading those via an
SWFLoader I may be able to avoid this rampant resource hogging but
it's sort of illogical from an application architecture standpoint
because this is ONE application.
As a developer, I can see plenty of places to streamline the
application but this simply isn't possible when dealing with the
client. They want this screen to look and act this way and that
screen to look and act the other way. I can talk about how if both
screens use the same layout and logic they can both use the same
template class, share static resources, blah blah until I am blue
in the face but it won't matter because they are the client and
they decide how the application is going to look--at the expense of
streamlining. That's just the real world. Then I have to somehow
make it work.
By the way... before you think ''just use view states!'', I do
use those--and bitwise logic flags for more complicated
configurations--it's still not enough, although it did cut approx
160 screens in documentation form down to just 20 in
implementation.
In worst case scenarios, I have to deny the client what they
want and if they ask me why, I have to reply ''it can't be done with
Flex''. Then their satisfaction in the product drops. Flex suddenly
isn't as incredible as it seemed at first. Doesn't matter how
pretty and animated the screens are when if you run them over an
hour your computer slows to a halt or .ttc fonts stop loading (HUGE
issue here in Japan).
I have yet to see a sample application that comes close to
the scale of our current project: A library book browser? neat but
that's just square one; A Commodore 64 emulator? cute. no place in
business; A real-estate browswer? in our project that would be the
equivalent of ONE SCREEN out of the entire application.
I like Flex. It's fun--on a small scale. But I never want to
develop a real world business application using it again. There are
way more (and way more skilled) Java, JSP, PHP, etc. etc.
developers out there than Flex developers who can make much more
robust applications. It's a shame the client got caught up in the
hype of Flex RIA before the technology was ready for the task.
Very long story short: Beware using Flex for an involved
application.
It's going to require exponentially more time than a smaller,
less ambitious project--especially if you don't purchase FDS. And
oh my god implementing a Flex application on a legacy Struts
framework... kill me now! As much as I hate ''page-refresh''
applications, Flex (both 1.5 and 2.0) has not proven to be the
god-send that I had hoped and dreamed it would be as a developer.
What can you expect, though? It's only been out a few years.... And
as far as clients' perspectives go, the price for FDS also
certainly doesn't help make it appealing. That is why it is so
embarrassing to tell them their dream application is quickly
becoming an egregious memory hog.
Anyway, good luck if you take on your project with flex. Just
be careful!
jpwrunyan,
Sounds like your application is huge. Can I ask what it is?
Mine is for a small newspaper. I have ~15-18 dynamic pages and a
database, using FDS.
Could you give us some info on your application, such as
initial download size, what kind of content you are displaying, and
whatever else you think would be relevant.
I tried what you were talking about, and left my page up for
24 hours, its still up and uses about 470MB of RAM. I haven't had a
problem at all with processor usage, but then again all the
Macs/PCs I have here are either dual CPU or dual core with
1.5GB-4GB of RAM as well as decent GPUs. I have looked at my
application from some of my PCs at home, all are single core (P4,
AMD64, AMD AthlonXP, Centrino) with 512MB-1GB of RAM, and I haven't
had much of an issue. I also haven't tested the application
extensively on these machines yet. I'm going to cut back on some of
the transitions and effects I have. The scroll/wipe effects and
transitions seem to use a lot of RAM and processor cycles.
A soltion to the problem of a lot of RAM being used might be
to unload/reload the application when the program is idle. I can
think of how this would be done, but without testing it I can't be
sure that it will work, or even help. You might be able to detect
when the application has been idle, for say.. 2 hours, or
whatever.. after this 2 hours, you might be able to force the
application to unload, then load again. I'm not sure if that would
solve the problem of massive RAM usage, or even help at all.. but
you might want to try it out on a sample application to see if it
could work. Another thought along the same line is to unload
resources as they are not being used, I have no idea if that is
possible but might be worth looking into, I'm going to look into
these things myself.
Let me know what you think...
Edit: More info--- the application currently uses 470MB of
RAM and 6-15% CPU at idle. This is on my development machine, with
an AMD 64 X2, dual 2.0Ghz, 4GB RAM, and 6800XT 256MB video card...
running Windows XP 64bit.
I have some potentially useful information...
If you haven't read about deferred cration and container
creationPolicy, you might want to go to the docs.
Flex creates all components and containers in an application
on load unless their creationPolicy is set to 'none'. You can set a
container's creationPolicy to 'none' making it not be created on
the application load. To make the container load, you call
containerName.createComponentsFromDescriptors() . This noticably
decreased my application startup time. However, I've decided not to
use it because of the delay it causes when you call the container
to be created. The delay is small, but it causes any appear effects
you have to not show because the container takes too long to load.
If you have no effects in the showEffect property of the container,
this is probably still a good idea.
The other option is ordered creation. You set
creationProperty=''queued'' and creationIndex=''(number here)'' and all
of the containers are loaded in the order you set, which results in
a shorter percieved startup time.
A few components/controls support the unload command. Those
being Loader, LoaderInfo and SWFLoader. There is also an UNLOAD
event. When using a Loader to load content, previous content is
unloaded prior to the new content being loaded.. this doesn't seem
like it would be very helpful in reducing RAM usage.
I haven't been able to find anything on application idle,
resume, or anything like that yet. Something might be able to be
performed by using a timer and catching the mouse over or focus or
something like that.. but its looking doubtful.
I've been busy so I haven't had a chance to post this... but
my site is live...
Feel free to check it out and leave some
feedback/comments/suggestions on here if you wish.
www.suvozonline.com
I know the initial load time is a little slow, I need to cut
down size/quality of the embedded images.
Jayson,
I took a look at your site and think you would benefit by
checking out this component created by Quietly Scheming.
http://www.quietlyscheming.com/blog/2007/01/23/some-thoughts-on-doubt-on-flex-as -the-best-option-orhow-i-made-my-flex-images-stop-dancing/
Good luck
Woah thats awesome, that problem is annoying for me. I just
downloaded the component. Looks like I'm going to learn something
new today!
Thanks!
Jayson,
sorry for the late reply.
My application is a order receival, billing, and dispatching
system. I really can't say too much about it. It is not an internet
app. It is for use on an intranet. Anyway, my issues are all
primarily related to garbage collection. I am overhauling the thing
to use modules (as of 2.0.1) but still have a heck of a time with
garbage collection. I think basically there are still too many bugs
in the Adobe Flex framework components that haywire even modular
apps (which are supposed to be able to readily free up resources).
My shell app download is currently about a 300 meg. The internal
modules are smaller (like 30-200 kb).
I don't follow what you mean by reloading the application. Do
you mean with navigateToURL()? In the middle of a task this could
be a very bad thing as queried/processed data would be lost.
Holding it in session or a local object, etc is the only thing I
can think of in such a case and that is not something I want to
debug.
Anyway, for me it is not the application's static state that
is the problem. It's when the user uses it over a long period of
time, loading and reloading screens that don't get properly removed
from memory that problems occur. Some memory leakage I can
handle... but not megabytes worth per screen load. This inherent
tendency to leak coupled with the extreme difficulty of not just
finding the leak but also fixing it (if even possible! ie:
PopUpManager) make me reluctant to consider Flex seriously as a
large legacy application front-end.
And before someone suggests it, let me add: weakly
referencing listeners is not enough!
Are you saying your swf file is 300 MB? How long have you
been working on this application? Something is not right if the
Shell is 300 meg? WOW , some operating systems are't much more than
that. This is very unusual. I have been using flex since 2.0 came
out and built several 20+ screen systems with no problems. Are you
includinge a lot of data in the swf file or using remoting to get
data as needed for each screen?
jpwrunyan,
Reloading the application is out of the question, it might
not be possible anyway. That was just an idea I had, but I have
since researched it.
What is causing your shell application to be so large? Mine
is ~2mb and I thought that was big. However, intranet is a
different story. Especially if you're running on a gigabit or fiber
network, then 300mb is nothing.
