Setup used in Greek Schools

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Setup used in Greek Schools

David Groos
I'm thinking that there are more people than just myself who would like to know this info so am asking here. Right, Alkis, you are probably the knowledge font here! Basically, what's the ltsp-pnp lab setup for next school year in the Greek Schools?

I'm looking for a (hopefully quick-booting) modern yet stable configuration. I'll be creating the new install in a month or 6 weeks. I'll be maintaining 5 classrooms including my own, each setup will use the teacher computer as the ltsp-pnp server. Probably not important, but I'll be using the 2 nic setup and a single gig --> (12-36 port) 100 mb switch. I imagine this is already written out online but have not succeeded in finding it. Each machine will have 2 gigs RAM and be maybe 5-7 year old.

Any preference for a browser or tricks to lighten the load of the image?

Thanks for your ltsp-in-schools leadership,
David G

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Re: Setup used in Greek Schools

Άλκης Γεωργόπουλος
Hi David, sorry but I don't have the time to write an extensive how-to
(I already maintain one in Greek :)), so I'll only mention a few tips:

* We're still using Ubuntu 12.04.x because we have extremely varying
hardware, so some schools need the old Xorg and kernel from 12.04.1,
while other schools need the new ones from 12.04.5, and there were even
schools that needed a new kernel and an old Xorg.
That's due to unfortunate regressions of the newer software.
We also have an issue with Ubuntu 14.04 keyboard layout not working
properly in Unity/Gnome/Gnome-flashback, and another one with
gnome-keyring making thousand of files with SSHFS (LP: #1321922).
These 3 issues maybe don't affect many of the users here, so you can
probably just go ahead and use 14.04.

* I recently committed in LTSP a few fixes for Unity, so if you'll be
using the Greek schools PPA, you can select any desktop environment that
you want.
Gnome-flashback and Mate are also good choices, especially if you also
have thin clients where 3D doesn't work over the network and software
rendering is used instead, making Unity extremely slow.

* About the flow control issue (gigabit server, 100mbps clients) we've
recently updated our /etc/network/if-up.d/sch-scripts script so that it
works in all cases, so you can just follow this how-to I've written:
https://help.ubuntu.com/community/UbuntuLTSP/FlowControl

* Firefox is a good browser. Sometimes a newer flash is needed though,
so it's nice to also have google-chrome installed, which has flash
version 18 instead of 11.

* And of course I always suggest to people to follow the ltsp-pnp page,
as it makes installation and maintenance much easier:
https://help.ubuntu.com/community/UbuntuLTSP/ltsp-pnp

Cheers,
Alkis

On 10/06/2015 07:12 πμ, David Groos wrote:

> I'm thinking that there are more people than just myself who would like
> to know this info so am asking here. Right, Alkis, you are probably the
> knowledge font here! Basically, what's the ltsp-pnp lab setup for next
> school year in the Greek Schools?
>
> I'm looking for a (hopefully quick-booting) modern yet stable
> configuration. I'll be creating the new install in a month or 6 weeks.
> I'll be maintaining 5 classrooms including my own, each setup will use
> the teacher computer as the ltsp-pnp server. Probably not important, but
> I'll be using the 2 nic setup and a single gig --> (12-36 port) 100 mb
> switch. I imagine this is already written out online but have not
> succeeded in finding it. Each machine will have 2 gigs RAM and be maybe
> 5-7 year old.
>
> Any preference for a browser or tricks to lighten the load of the image?
>
> Thanks for your ltsp-in-schools leadership,
> David G
>
>


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Re: Setup used in Greek Schools

David Groos
Thanks Alkis for this information!

Based on what I now know, I'll...
--Continue with ltsp-pnp, all clients FAT.
--Give 14.04 a try with Unity/Gnome/Gnome-flashback/Mate and do some simple boot-time benchmarking.
--Read up on flow control and do some experiments using the Epoptes benchmarking tool (both things of which I was unfamiliar).
--Continue to use both ff and gc (now I know why gc works better sometimes) even though ff is my preferred as it is more open sourc-esque
--Update the 2 nic install page for 14.04

Questions:
--I could put 2 hard drives on the classroom server and install the system on one HD and /home on another HD. Seems like that would significantly improve performance during those times when some clients were booting and others were logging in, but that's just an idea. Your guess/knowledge on this?
--Any additional "suggested reading" pages? With google translate my Greek goes from 0 to 60 in under 10 seconds ;)

Finally:
--What's a way/s I can contribute back to your/our efforts of ubuntu/ltsp in ed? I saw this page: https://answers.launchpad.net/sch-scripts/+question/228810 but it's not too current. I'm doing my own bit to resist the corporate, self-labeled "education-reform" movement whose advocates think they can ignorantly apply simplistic free-market principles to improve education. You can imagine how that plays out in big-district technology bureaucracies. From what I read, this corporate ed-reform movement is world-wide. [stepping back down from the soap box...]

BTW Here's a blog post by a Finnish guy I've followed for many years. He has many important things to say about modern/future education and about technology and open source as well. http://teemuleinonen.fi/2015/06/09/why-freelibreopen-source-in-learning-is-important/

Enjoy your summer,
David G

On Wed, Jun 10, 2015 at 1:07 AM Alkis Georgopoulos <[hidden email]> wrote:
Hi David, sorry but I don't have the time to write an extensive how-to
(I already maintain one in Greek :)), so I'll only mention a few tips:

* We're still using Ubuntu 12.04.x because we have extremely varying
hardware, so some schools need the old Xorg and kernel from 12.04.1,
while other schools need the new ones from 12.04.5, and there were even
schools that needed a new kernel and an old Xorg.
That's due to unfortunate regressions of the newer software.
We also have an issue with Ubuntu 14.04 keyboard layout not working
properly in Unity/Gnome/Gnome-flashback, and another one with
gnome-keyring making thousand of files with SSHFS (LP: #1321922).
These 3 issues maybe don't affect many of the users here, so you can
probably just go ahead and use 14.04.

* I recently committed in LTSP a few fixes for Unity, so if you'll be
using the Greek schools PPA, you can select any desktop environment that
you want.
Gnome-flashback and Mate are also good choices, especially if you also
have thin clients where 3D doesn't work over the network and software
rendering is used instead, making Unity extremely slow.

* About the flow control issue (gigabit server, 100mbps clients) we've
recently updated our /etc/network/if-up.d/sch-scripts script so that it
works in all cases, so you can just follow this how-to I've written:
https://help.ubuntu.com/community/UbuntuLTSP/FlowControl

* Firefox is a good browser. Sometimes a newer flash is needed though,
so it's nice to also have google-chrome installed, which has flash
version 18 instead of 11.

* And of course I always suggest to people to follow the ltsp-pnp page,
as it makes installation and maintenance much easier:
https://help.ubuntu.com/community/UbuntuLTSP/ltsp-pnp

Cheers,
Alkis

On 10/06/2015 07:12 πμ, David Groos wrote:
> I'm thinking that there are more people than just myself who would like
> to know this info so am asking here. Right, Alkis, you are probably the
> knowledge font here! Basically, what's the ltsp-pnp lab setup for next
> school year in the Greek Schools?
>
> I'm looking for a (hopefully quick-booting) modern yet stable
> configuration. I'll be creating the new install in a month or 6 weeks.
> I'll be maintaining 5 classrooms including my own, each setup will use
> the teacher computer as the ltsp-pnp server. Probably not important, but
> I'll be using the 2 nic setup and a single gig --> (12-36 port) 100 mb
> switch. I imagine this is already written out online but have not
> succeeded in finding it. Each machine will have 2 gigs RAM and be maybe
> 5-7 year old.
>
> Any preference for a browser or tricks to lighten the load of the image?
>
> Thanks for your ltsp-in-schools leadership,
> David G
>
>


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Re: Setup used in Greek Schools

Adam Fischer
Hi David,

If boot time is a concern, what I have been doing with both LTSP setups
and stand-alone workstations is use an SSD and mount / to it, and use a
big HD and mount /home to it (sometimes /var as well).  Alternatively, I
sometimes mount just /boot to the SSD instead.

If you don't use an SSD for the booting, it's doubtful you'll get any
real improvement on boot time.  You really don't need a big one, either.

If you're new to using SSD's, and want to give it a try, make sure AHCI
is enabled in your BIOS before you do the install, as well.  I missed
that in one of my most remote installations and have been paying for it
for a long time (takes forever to read packages, and other things).

Thanks!
Adam Fischer


On 06/10/2015 09:31 AM, David Groos wrote:

> Thanks Alkis for this information!
>
> Based on what I now know, I'll...
> --Continue with ltsp-pnp, all clients FAT.
> --Give 14.04 a try with Unity/Gnome/Gnome-flashback/Mate and do some
> simple boot-time benchmarking.
> --Read up on flow control and do some experiments using the Epoptes
> benchmarking tool (both things of which I was unfamiliar).
> --Continue to use both ff and gc (now I know why gc works better
> sometimes) even though ff is my preferred as it is more open sourc-esque
> --Update the 2 nic install page for 14.04
>
> Questions:
> --I could put 2 hard drives on the classroom server and install the
> system on one HD and /home on another HD. Seems like that would
> significantly improve performance during those times when some clients
> were booting and others were logging in, but that's just an idea. Your
> guess/knowledge on this?
> --Any additional "suggested reading" pages? With google translate my
> Greek goes from 0 to 60 in under 10 seconds ;)
>
> Finally:
> --What's a way/s I can contribute back to your/our efforts of
> ubuntu/ltsp in ed? I saw this page:
> https://answers.launchpad.net/sch-scripts/+question/228810 but it's not
> too current. I'm doing my own bit to resist the corporate, self-labeled
> "education-reform" movement whose advocates think they can ignorantly
> apply simplistic free-market principles to improve education. You can
> imagine how that plays out in big-district technology bureaucracies.
>  From what I read, this corporate ed-reform movement is world-wide.
> [stepping back down from the soap box...]
>
> BTW Here's a blog post by a Finnish guy I've followed for many years. He
> has many important things to say about modern/future education and about
> technology and open source as well.
> http://teemuleinonen.fi/2015/06/09/why-freelibreopen-source-in-learning-is-important/
>
> Enjoy your summer,
> David G
>
> On Wed, Jun 10, 2015 at 1:07 AM Alkis Georgopoulos <[hidden email]
> <mailto:[hidden email]>> wrote:
>
>     Hi David, sorry but I don't have the time to write an extensive how-to
>     (I already maintain one in Greek :)), so I'll only mention a few tips:
>
>     * We're still using Ubuntu 12.04.x because we have extremely varying
>     hardware, so some schools need the old Xorg and kernel from 12.04.1,
>     while other schools need the new ones from 12.04.5, and there were even
>     schools that needed a new kernel and an old Xorg.
>     That's due to unfortunate regressions of the newer software.
>     We also have an issue with Ubuntu 14.04 keyboard layout not working
>     properly in Unity/Gnome/Gnome-flashback, and another one with
>     gnome-keyring making thousand of files with SSHFS (LP: #1321922).
>     These 3 issues maybe don't affect many of the users here, so you can
>     probably just go ahead and use 14.04.
>
>     * I recently committed in LTSP a few fixes for Unity, so if you'll be
>     using the Greek schools PPA, you can select any desktop environment that
>     you want.
>     Gnome-flashback and Mate are also good choices, especially if you also
>     have thin clients where 3D doesn't work over the network and software
>     rendering is used instead, making Unity extremely slow.
>
>     * About the flow control issue (gigabit server, 100mbps clients) we've
>     recently updated our /etc/network/if-up.d/sch-scripts script so that it
>     works in all cases, so you can just follow this how-to I've written:
>     https://help.ubuntu.com/community/UbuntuLTSP/FlowControl
>
>     * Firefox is a good browser. Sometimes a newer flash is needed though,
>     so it's nice to also have google-chrome installed, which has flash
>     version 18 instead of 11.
>
>     * And of course I always suggest to people to follow the ltsp-pnp page,
>     as it makes installation and maintenance much easier:
>     https://help.ubuntu.com/community/UbuntuLTSP/ltsp-pnp
>
>     Cheers,
>     Alkis
>
>     On 10/06/2015 07:12 πμ, David Groos wrote:
>      > I'm thinking that there are more people than just myself who
>     would like
>      > to know this info so am asking here. Right, Alkis, you are
>     probably the
>      > knowledge font here! Basically, what's the ltsp-pnp lab setup for
>     next
>      > school year in the Greek Schools?
>      >
>      > I'm looking for a (hopefully quick-booting) modern yet stable
>      > configuration. I'll be creating the new install in a month or 6
>     weeks.
>      > I'll be maintaining 5 classrooms including my own, each setup
>     will use
>      > the teacher computer as the ltsp-pnp server. Probably not
>     important, but
>      > I'll be using the 2 nic setup and a single gig --> (12-36 port)
>     100 mb
>      > switch. I imagine this is already written out online but have not
>      > succeeded in finding it. Each machine will have 2 gigs RAM and be
>     maybe
>      > 5-7 year old.
>      >
>      > Any preference for a browser or tricks to lighten the load of the
>     image?
>      >
>      > Thanks for your ltsp-in-schools leadership,
>      > David G
>      >
>      >
>
>
>     --
>     edubuntu-users mailing list
>     [hidden email] <mailto:[hidden email]>
>     Modify settings or unsubscribe at:
>     https://lists.ubuntu.com/mailman/listinfo/edubuntu-users
>
>
>

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Re: Setup used in Greek Schools

Άλκης Γεωργόπουλος
In reply to this post by David Groos
On 10/06/2015 05:31 μμ, David Groos wrote:
> Thanks Alkis for this information!
>
> Questions:
> --I could put 2 hard drives on the classroom server and install the
> system on one HD and /home on another HD. Seems like that would
> significantly improve performance during those times when some clients
> were booting and others were logging in, but that's just an idea. Your
> guess/knowledge on this?

The root file system (/) doesn't matter much as it's aggressively cached
in RAM, provided of course that your server does have enough RAM.
But it's nice to put /home in an SSD, since many users need write access
there in parallel. I have no benchmarks about that yet though.


> --Any additional "suggested reading" pages? With google translate my
> Greek goes from 0 to 60 in under 10 seconds ;)

Nah, the links in the launchpad answer below cover all I've got. :)


> Finally:
> --What's a way/s I can contribute back to your/our efforts of
> ubuntu/ltsp in ed? I saw this page:
> https://answers.launchpad.net/sch-scripts/+question/228810 but it's not
> too current.

Most of the information there is still valid.

I think that one good way for people to contribute would be to sponsor
specific tasks that they care to see implemented, for example:
  * "I'm giving $100 to any developer that adds the ability to the
edubuntu live dvd media to boot a whole classroom of LTSP fat clients"
  * "I'm contributing $200 for the move to LTSP 6"
  * "I'm giving 50€ to any developer that solves launchpad bug #xxx".

That would support the existing development teams, and it could possibly
attract even more developers. FLOSS is a very good development model but
of course no developer will use it if he can't cover his expenses.

And of course documentation etc contributors are always welcome, but
unfortunately they usually don't stay around for a long time.


Btw, about boot speed, the clients should load in about a minute (for
some clients here, min=10 seconds, max=70), if they don't you might want
to check your network speed.

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Re: Setup used in Greek Schools

Veli-Matti Lintu
2015-06-11 8:03 GMT+03:00 Alkis Georgopoulos <[hidden email]>:
On 10/06/2015 05:31 μμ, David Groos wrote:
Thanks Alkis for this information!

Questions:
--I could put 2 hard drives on the classroom server and install the
system on one HD and /home on another HD. Seems like that would
significantly improve performance during those times when some clients
were booting and others were logging in, but that's just an idea. Your
guess/knowledge on this?

The root file system (/) doesn't matter much as it's aggressively cached in RAM, provided of course that your server does have enough RAM.
But it's nice to put /home in an SSD, since many users need write access there in parallel. I have no benchmarks about that yet though.

It's also possible to use SSD as a cache layer for a normal spinning drive using dm-cache (or bcache, etc.). dm-cache has worked well for us on /home partitions. Writes are fast and most of the user data seems to sit there unused, so also most reads are fast.

In our case we have home partition on LVM and SSD drive is used as a cache layer. Those are then combined to cached-home device that is mounted as /home. We wrote some tools to manage the dm-cache partitions (https://github.com/opinsys/dmcache-utils), but I've understood that there's now also lvmcache.


Veli-Matti

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Re: Setup used in Greek Schools

David Groos
Thanks all for weighing in. I didn't know about the role of caching for root file system (i.e. /) in LTSP but it makes complete sense why /home should get the ssd love not the root which I had supposed. I'm now questioning if the 4 gigs of RAM that I used for the "teacher computer" in my classroom was enough. Any sense of amount of RAM that would mostly avoid this bottleneck? Let's say one was running 14.04 Ubuntu.

The dm-cache sounds the most eloquent solution but is beyond my tech knowledge/resources so using the SSD for /home seems like the way to go. If I can't get any SSD's, is there any reason to use 2 standard HD's in some format such as a RAID or dividing off the /home partition? Our teacher computers will be i5's with space for at least 2 HD's.

BTW, here's a nice 2014 TEDx presentation on Libre software by Richard Stallman--probably some have already seen it: http://teemuleinonen.fi/2015/06/09/why-freelibreopen-source-in-learning-is-important/.



On Thu, Jun 11, 2015 at 2:20 AM Veli-Matti Lintu <[hidden email]> wrote:
2015-06-11 8:03 GMT+03:00 Alkis Georgopoulos <[hidden email]>:
On 10/06/2015 05:31 μμ, David Groos wrote:
Thanks Alkis for this information!

Questions:
--I could put 2 hard drives on the classroom server and install the
system on one HD and /home on another HD. Seems like that would
significantly improve performance during those times when some clients
were booting and others were logging in, but that's just an idea. Your
guess/knowledge on this?

The root file system (/) doesn't matter much as it's aggressively cached in RAM, provided of course that your server does have enough RAM.
But it's nice to put /home in an SSD, since many users need write access there in parallel. I have no benchmarks about that yet though.

It's also possible to use SSD as a cache layer for a normal spinning drive using dm-cache (or bcache, etc.). dm-cache has worked well for us on /home partitions. Writes are fast and most of the user data seems to sit there unused, so also most reads are fast.

In our case we have home partition on LVM and SSD drive is used as a cache layer. Those are then combined to cached-home device that is mounted as /home. We wrote some tools to manage the dm-cache partitions (https://github.com/opinsys/dmcache-utils), but I've understood that there's now also lvmcache.


Veli-Matti
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Re: Setup used in Greek Schools

David Groos
In reply to this post by Άλκης Γεωργόπουλος


On Thu, Jun 11, 2015 at 12:04 AM Alkis Georgopoulos <[hidden email]> wrote:

> Finally:
> --What's a way/s I can contribute back to your/our efforts of
> ubuntu/ltsp in ed? I saw this page:
> https://answers.launchpad.net/sch-scripts/+question/228810 but it's not
> too current.

Most of the information there is still valid.

I think that one good way for people to contribute would be to sponsor
specific tasks that they care to see implemented, for example:
  * "I'm giving $100 to any developer that adds the ability to the
edubuntu live dvd media to boot a whole classroom of LTSP fat clients"
  * "I'm contributing $200 for the move to LTSP 6"
  * "I'm giving 50€ to any developer that solves launchpad bug #xxx". 

That would support the existing development teams, and it could possibly
attract even more developers.
This is good to know--I've often wondered this, only thinking of the "donate $15 to LibreOffice/ $25 to Wikipedia etc" model. Actually, seems like a more targeted way of support and getting something specific--appealing to funders I'd think. I'll contact you back w/questions when I get nearer to something like that.
FLOSS is a very good development model but
of course no developer will use it if he can't cover his expenses.

And of course documentation etc contributors are always welcome, but
unfortunately they usually don't stay around for a long time.
Indeed. I expect I'll add/update a page or two in the process of setup this summer. It's nice that I actually know what school I'll be at next year AND that it's the same one as this year.


Btw, about boot speed, the clients should load in about a minute (for
some clients here, min=10 seconds, max=70), if they don't you might want
to check your network speed.
Wow, Almost 2 minutes for me. I'll try the epoptes benchmark tool and flow control

Thanks,
David
Did I mention that Stallman video... oh yeah, twice...  :-)

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RE: Setup used in Greek Schools

Job Cacka
In reply to this post by David Groos

Years ago, we used 64MB of RAM per thin client connection as a rule of thumb for calculating RAM. So if your class size is 25 thin clients you would want 64 MB * 25 = 1600 MB or 1.56 GB. I think this rule of thumb is old however. We were using LTSP 5 on Ubuntu 10.04 I believe. However if you doubled the RAM requirements you would still be under your 4GB.

 

Have fun!

  Job Cacka

 

From: [hidden email] [mailto:[hidden email]] On Behalf Of David Groos
Sent: Thursday, June 11, 2015 6:54 PM
To: Veli-Matti Lintu; Edubuntu Users Group
Subject: Re: Setup used in Greek Schools

 

Thanks all for weighing in. I didn't know about the role of caching for root file system (i.e. /) in LTSP but it makes complete sense why /home should get the ssd love not the root which I had supposed. I'm now questioning if the 4 gigs of RAM that I used for the "teacher computer" in my classroom was enough. Any sense of amount of RAM that would mostly avoid this bottleneck? Let's say one was running 14.04 Ubuntu.

 

The dm-cache sounds the most eloquent solution but is beyond my tech knowledge/resources so using the SSD for /home seems like the way to go. If I can't get any SSD's, is there any reason to use 2 standard HD's in some format such as a RAID or dividing off the /home partition? Our teacher computers will be i5's with space for at least 2 HD's.

BTW, here's a nice 2014 TEDx presentation on Libre software by Richard Stallman--probably some have already seen it: http://teemuleinonen.fi/2015/06/09/why-freelibreopen-source-in-learning-is-important/.

 

 

On Thu, Jun 11, 2015 at 2:20 AM Veli-Matti Lintu <[hidden email]> wrote:

2015-06-11 8:03 GMT+03:00 Alkis Georgopoulos <[hidden email]>:

On 10/06/2015 05:31 μμ, David Groos wrote:

Thanks Alkis for this information!

Questions:
--I could put 2 hard drives on the classroom server and install the
system on one HD and /home on another HD. Seems like that would
significantly improve performance during those times when some clients
were booting and others were logging in, but that's just an idea. Your
guess/knowledge on this?


The root file system (/) doesn't matter much as it's aggressively cached in RAM, provided of course that your server does have enough RAM.
But it's nice to put /home in an SSD, since many users need write access there in parallel. I have no benchmarks about that yet though.

 

It's also possible to use SSD as a cache layer for a normal spinning drive using dm-cache (or bcache, etc.). dm-cache has worked well for us on /home partitions. Writes are fast and most of the user data seems to sit there unused, so also most reads are fast.

 

In our case we have home partition on LVM and SSD drive is used as a cache layer. Those are then combined to cached-home device that is mounted as /home. We wrote some tools to manage the dm-cache partitions (https://github.com/opinsys/dmcache-utils), but I've understood that there's now also lvmcache.

 

 

Veli-Matti

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Re: Setup used in Greek Schools

Άλκης Γεωργόπουλος
On 12/06/2015 06:16 μμ, Job Cacka wrote:
> Years ago, we used 64MB of RAM per thin client connection as a rule of
> thumb for calculating RAM. So if your class size is 25 thin clients you
> would want 64 MB * 25 = 1600 MB or 1.56 GB. I think this rule of thumb
> is old however. We were using LTSP 5 on Ubuntu 10.04 I believe. However
> if you doubled the RAM requirements you would still be under your 4GB.


Currently we're using these formulas:
1) Server RAM = 1500 + 30*fat-clients + 300*thin-clients
2) Server CPU = 1500 + 30*fat-clients + 300*thin-clients
...the server CPU measured in passmark, e.g.
http://www.cpubenchmark.net/cpu.php?cpu=Intel+Core+i3-3220+@+3.30GHz
Average CPU Mark = 4210

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Re: Setup used in Greek Schools

David Groos
You know, this kind of info is not only useful as we implement LTSP, it's also useful as we advocate for LTSP/open source with school/district IT departments. Thanks for always sharing the work of the Greek Schools.

On Sat, Jun 13, 2015 at 8:05 AM Alkis Georgopoulos <[hidden email]> wrote:
On 12/06/2015 06:16 μμ, Job Cacka wrote:
> Years ago, we used 64MB of RAM per thin client connection as a rule of
> thumb for calculating RAM. So if your class size is 25 thin clients you
> would want 64 MB * 25 = 1600 MB or 1.56 GB. I think this rule of thumb
> is old however. We were using LTSP 5 on Ubuntu 10.04 I believe. However
> if you doubled the RAM requirements you would still be under your 4GB.


Currently we're using these formulas:
1) Server RAM = 1500 + 30*fat-clients + 300*thin-clients
2) Server CPU = 1500 + 30*fat-clients + 300*thin-clients
...the server CPU measured in passmark, e.g.
http://www.cpubenchmark.net/cpu.php?cpu=Intel+Core+i3-3220+@+3.30GHz
Average CPU Mark = 4210

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