Draw waveforms and hear them
A while back I thought it would be interesting to be able to draw arbitrary waveforms and then listen to how they sound. I had an audio engine just laying around, so I whipped up a quick application to do that.
Using the Acer Aspire One as a web server
Posted 14 years ago
My web site has been going up and down over the night. I've intentionally been trying to elicit reddit traffic so I can test different parameters for apache server optimization, to handle high traffic over slow connections.
A netbook can be ideal for a home web server. They are cheap, and use less power than a CFL light bulb. The only trade-off is that it won't reboot on a power failure. Fortunately, the built in UPS will sustain it through all but the longest power outages.
My Via Artigo died several weeks ago while I was using it. I have no air conditioner, so it must have been about 30 degrees which may have contributed to its demise. I took it apart and poked at it, but the monitor and disk light wouldn't light up. So ended up getting a $179 refurbished Acer Aspire One, which is now happily serving up this web site.
Specs
- 1.6 GHz Atom processor (with hyperthreading)
- 512 MB memory
- 8 GB SSD
- Wifi, ethernet, VGA ports
- 3 USB ports and 2 SD card slots (?!)
Initial experiences
I turned it on briefly and it had a linux based OS on it that boots up in a less than 5 seconds and looks confusingly like Windows XP. Enough about that.
Because I only install Ubuntu on USB keys, I was able to plug it in, boot up, and my web site was up and running in only minutes.
The fan is the quietest I have ever heard on any laptop. It makes almost no sound at all.
Lousy performance as a desktop system
My old Artigo had a Via 1 GHz CPU and 1 GB of memory, and it could be used as a desktop system. Not so with the Acer. Even with the increased processor power, the decrease in RAM eats up all the benefit. After installing Xubuntu, the system is too sluggish to handle common desktop tasks. It badly needs a RAM upgrade, but this requires you to completely disassemble it..
The tiny speakers are junk. Imagine listening to a movie through ear-buds one metre away. That's how bad it is. But it doesn't matter, because it's a server.
Handling Server Load
With Ubuntu 9.04, after a day of serving up moderate web activity, the Linux Atheros Wifi driver was stuck in a bad state so it was offline. I switched it to a plug-in cable and haven't had any more issues.
The system went non-responsive an hour after I posted my last comic strip. It had a blank screen and needed rebooting. However, I hadn't optimized apache2 yet. Using the approriate settings, I believe that it can handle about between 30 and 40 visits/minute, or anything reddit and ycombinator can throw at it. I'm still tweaking with the apache parameters, and I'll post something about them soon.
Things to watch out for when running a home web server
- Ensure that MaxClients is set to a reasonable value (memory divided by 7 MB?) in your apache2.conf file. If you come home to find your machine non-responsive and thrashing, this is the cause. To be ultra-safe, you can flip the "KeepAlive" setting to Off, but your pages will load more slowly.
- If serving over a dynamic IP address, make sure your machine is configured to automatically update it. I installed ddclient to do this, but on Ubuntu it wasn't automatically restarting after a reboot.
- As always, be careful with large images. Save photos as low quality JPGs, and screenshots as 16-colour .PNG files. Don't put up anything over 50 kb.
- The limiting factor is bandwidth, not CPU. Enable gzip compression using 'a2enmod deflate'
Steve Hanov makes a living working on
Rhymebrain.com,
PriceMonkey.ca,
www.websequencediagrams.com,
and Zwibbler.com. He lives in
Waterloo, Canada.
Post comment
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David Hill
ten years ago
Thanks for this article! Glad to see I'm not the only one who sees the value in using my old Netbook as a server... I just did a similar write up on the merits of Netbooks for serving web requests... haven't gotten into tuning Apache yet though. Mine has 2 Gig of memory so I haven't seen any performance issues yet to speak of, even with using a portion of it for memcached.
davidvhill.com/article/why-you-should-use-a-netbook-for-your-webserver if you are interested.
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Donald
eleven years ago
I just found this post; I've been thinking about doing something similar.
I don't see a search function here, is the Netbook still working as a server?
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mister person
eleven years ago
you will probably get less latency if you upgrade the WiFi card (located under the touch pad when you disassemble) or use a cat5e cable instead of wireless. many things from lights, Bluetooth, microwave ovens, and people trying to connect to your network slow your network speed down.
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John Trashtalker
eleven years ago
Apache is an absolute joke. Allocating a full thread stack for every request was the dumbest design decision ever made. Although I expect nothing less from the morons who also gave us Apache Ant.
Boasting about how many 8MB stacks your tiny server can sustain is like boasting about how thick the lead walls are on your airliner's fuselage. Completely missing the point and utterly retarded.
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Simon
13 years ago
I use an Aspire One as a netbook pretty reasonably thanks to Ubuntu Lynx Netbook Edition and Chrome / optimised Firefox. I hadn't thought of using it as a webserver though, neat idea. Consider the SheevaPlug range though - designed for the job and an excellent product.
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Steve Hanov
13 years ago
Nikos: It's been working continuously for 11 months now. However, summer in my house kills equipment so we will see what happens!
I have a way of switching things to a backup within a few hours if the Acer fails.
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Nikos
13 years ago
cool idea. running web server on a laptop but what about the heating?
it will soon die?!
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rick
13 years ago
Hi Steve,
I've got an aspire one that I also use as a home server. The memory upgrade is fairly easy and takes less than 10 minutes. I've upped the RAM on mine to 2GB.
I also swapped out the crummy atheros card with a broadcom one I got off ebay. Highly recommend this change if you're serious about using it wirelessly!
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George Jetson
13 years ago
Very good idea using a netbook for a server. Save a lot on energy bills not to mention sound levels.
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batteries99
13 years ago
input volts: AC 100V-240V
output volts: 15-21 Volt( DC )
power: 30W
Acer Aspire One Laptop AC Adapter for Sale,25% off!
www.espow.ca/laptop-ac-adapter/acer-aspire-one.htm
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Steve Hanov
13 years ago
Three seconds isn't too long at all. There is plenty of text on my pages to read while the images are loading for two more seconds.
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James
14 years ago
It can handle twenty visits per minute? Are you talking about smoothed load? Does that mean your website has an average latency of three seconds? That's way too long dude.
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Leonardo Vaz
14 years ago
Don't forget upgrading the BIOS after adding more RAM memory. Did it some weeks ago and the SSD just died. After a week trying use SD cards I was about to throw it to the garbage can and I had the idea of upgrade the BIOS to the latest version and it worked. ;)
Regards from South of Brazil,
Leo
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Jamse
14 years ago
It's probably not the cost of a memory module but rather the installation of said memory stick that is the problem:
"It badly needs a RAM upgrade, but this requires you to completely disassemble it.. " that
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ro89
14 years ago
use lighttpd + php + apc or just add apc php cache. That will speed up your php scripts. Also try to add mysql caching and app level caching to disk.
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Matthias
14 years ago
Setting keepalive = 0 is not such a good idea.
It means each image needs a new HTTP connection, which wastes bandwidth.
I was able to have around 80 concurrent apache processes on a 128 meg VPS. The key is to do it without any server side processing.
A while back I thought it would be interesting to be able to draw arbitrary waveforms and then listen to how they sound. I had an audio engine just laying around, so I whipped up a quick application to do that.
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