[K12OSN] Poor performance woes

Tue Sep 20 20:57:42 UTC 2011

On 09/20/2011 04:34 PM, Dean Jones wrote:
> +1 on the 64 bit flash.  Much better performance if the problem is
> flash related.

The page he's trying to load has no flash.  When I was testing, I had 
all the TC's playing full-screen youtube vids.  It was a little laggy, 
but it did not fall to its knees.

> As you know Windows will perform poorly on those clients as well
> regardless of the server specs.  It is dated hardware with little
> video memory.

I know that full well.  I doubt the ability of the school board to 
understand that though until they give it a whirl.  The TC's actually 
have HD's in them with Win2K.  I've considered booting into that and 
giving them a demo.

To add injury to insult, the board member I mentioned previously is 
bringing in a "computer person" to "evaluate our needs".  Grrrr. 
Nevermind that I'm a software engineer with over 25 years of experience.

> You can try nbdroot for a slight speed increase over NFS if the
> problem is file i/o related.

It's already using nbd.

Thanks for your suggestions.

> On Tue, Sep 20, 2011 at 1:12 PM, David Hopkins<dahopkins429 at gmail.com>  wrote:
>> So, runs fine at server console, but lags severely at the thin client with
>> the same account.  Are you certain that the clients are running at 100Mb
>> full duplex?  If you've enabled a shell at the client can you check to see
>> what ifconfig reports at the client?  I would check memory/performance at
>> the client with top (in a shell, add SCREEN_02=shell in lts.conf, ctl-alt-f2
>> to access it at the client) while the page is being displayed from the GUI
>> login session just to convince myself it isn't a load issue at the client.
>>
>> Also, Adobe has a 64bit Flash for linux (v11) available as beta. I've been
>> running that for the last couple of weeks (since it was released IOW) on my
>> systems (Ubuntu 10.04 with LTSP packages added).
>> http://labs.adobe.com/downloads/flashplayer11.html It definitely runs better
>> than the 32bit flash with nswrapper.  Installation was just a matter of
>> uninstalling the 32bit flash and copying the 64bit version to the correct
>> plugins directory.
>>
>> Those are the things that I'd check first.
>>
>> Sincerely,
>> Dave Hopkins
>> Newark Charter School
>>
>> On Tue, Sep 20, 2011 at 3:18 PM, Jomegat<jomegat at jomegat.com>  wrote:
>>>
>>> I have a K12Linux setup based on EL6-64.  The TC's are ancient i686's with
>>> 256M RAM and 10/100 nics.  The TS has a gigE NIC, and between the TS&  TCs
>>> is a managed switch with 2 gigE ports and 24 10/100 ports.  The TS is
>>> connected via one of the gigE's.
>>>
>>> We have a student who is having real performance problems when he loads a
>>> page.  I went in today to be there while he was experiencing woe, and ran
>>> the system monitor applet.
>>>
>>> When he loads the web page - with no flash in it that I can find - the
>>> network maxes out at 12MiB/sec, and it takes an eternity for the page to
>>> load.  He reports that sometimes this particular page will cause the TC to
>>> crash (black screen with text followed by login screen), but he was not able
>>> to reproduce that while I was there.  I suspect there is some user error
>>> involved in the crash scenario, but it will be difficult to prove.
>>>
>>> I had tried running firefox as a local app last month, but the school
>>> needs flash, and it requires 512M.  Performance on these TC's was
>>> substantially worse when running FF as a local app, so I backed off of that.
>>>
>>> The page he was trying to load is password protected, but I had him ctrl-U
>>> while he had it open, and save the source to a file which I can share if
>>> need be.  It is filled with javascript, but I'm not sure that's the culprit
>>> (though it seems the most likely suspect).  I found no .flv, FLV, .swf, or
>>> .SWF in the file anywhere.
>>>
>>> As an experiment, I connected a monitor, keybd, and mouse directly to the
>>> server and had him login there.  The page loads just fine that way.  That
>>> might be a possible solution, but for some reason, the display is incredibly
>>> blurry.  If I make that permanent, I'd have to run some cable through the
>>> wall (they're pinched in the door right now, and barely reach).
>>>
>>> Before they called me in to look at this, he had been bringing his mom's
>>> laptop to school so he could do his work (it's an online course).  If it
>>> crashes while he is taking a quiz, he loses a test attempt or gets a bad
>>> grade, so this has to be reliable.
>>>
>>> His mom is on the school board, and she is pushing the school to abandon
>>> LTSP in favor of a Windows solution.  They think that if they install some
>>> flavor of windows on the TC's they will get better performance, but I
>>> believe they won't, as flash will need 512M no matter the OS.  I think they
>>> will need all new PC's if they go that route.
>>>
>>> I am on the cusp of losing my network to Windows, at which point I will
>>> resign my post as unpaid volunteer sysadmin, so if I sound a little
>>> desperate, now you know why.
>>>
>>> Any help here would be greatly appreciated.
>>>
>>> --
>>> Jim Thomas            Principal Applications Engineer  Bittware, Inc
>>> jthomas at bittware.com  http://www.bittware.com    (603) 226-0404 x536
>>> The problem with the future is that it keeps turning into the present -
>>> Hobbes
>>>
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>>
>>
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-- 
Jim Thomas            Principal Applications Engineer  Bittware, Inc
jthomas at bittware.com  http://www.bittware.com    (603) 226-0404 x536
The problem with the future is that it keeps turning into the present - 
Hobbes