Astroserver CPU load

[Astrofriend]

Maybe you have plans to build an astroserver to control your equipment. One thing to figure out is how fast computer do you need. Too fast and it take more power then necesary (my computer is battery operated), to slow and it will not work properly.

I have made a table over the CPU loads on my Astroserver during different work:
http://www.astrofriend.eu/astronomy/tutorials/tutorial-cpu-load/tutorial-cpu-load.html

Maybe it could be to some help for you.

/Lars

[MarsG76]

I found that you do not need a too powerful PC to run astro gear and software, you're comparison reflects this, 70% PCU load on a 1.66GHz chip.

I used a 1.66GHz VAIO for my astro control and it was fine until the laptop died.... now I use a 2.0GHZ Core2Due VAIO, also a old (8 year old) computer, and its more than enough power, that running PHD, Starry Night Pro 6, APT, ICap, NexRemote and sometimes PS on multiple desktops all while serving via VNC, and it doesn't skip a beat.

Processing is the only area where I opt to use my desktop, which is much more powerful.

 

[Astrofriend]

Hi MarsG76,

Yes I'm satisfied with my computer and what it can do.

But there is another issue, to power the computer I need 19 volt. As a power sourche I have a small carbattery that have constant charge, 13.7 Volt and have a DC/DC converter between, 13.7 to 19 volt. Next time I build a new astroserver I will take a PC that can be powered direct from 12 (13.7) Volt. It will reduce the power losses and need less space. I think that some of the Intel NUC mini PC models have that opportunity.

It's not a big problem and no hurry to solve. As it now my system can run 4 hours during powergrid loss.

/Lars

[cjdawson]

Whilst I already knew that you don't need a really powerful pc to run astro stuff, there are times when having more power available is a bonus (platesolving) when I decided to switch from a computerless system back to having cameras controlled by a computer I needed to get a machine for the job.  I decided to get a laptop, actually, I ended up going to PC world, seeing what they had available and got one that day.  What I ended up with was a HP Pavillion i5 with 15" screen.

The key features that I went for were...

1. It wasn't an I3.  I only see them as good enough for email and web browsing.     i5 Processor is quad core and fairly efficient too.

2. 256GB SSD - no spinning disk, so less to go wrong.

3. USB 3.0   "Future proof" well ok ok, at least it's up to date.

4. 45 watt power supply.     45W for the whole thing, that's much better than any laptop I'd had before.

 

The 256GB SSD is big enough to be able to store all the software and data that I need, including the ANSVR plate solving libraries.

The 45W power supply is a huge bonus compared to the last time I'd used a laptop (it needed 150W for my laptop before)

 

The laptop is dedicated to Astronomy, it doesn't have anything else installed, and it works like a dream.   Whilst there's alot of power available, it doesn't need it most of the time, and thanks to Intel's speedstep technology, it spends most of the time running at minimum speed, so it's really efficient.    I've got it running ASCOM, PHD2, Carts De Ceil, Sequence Generator Pro 3 (with PlateSolve2), Sharp Cap, Nebulosity, ANSVR and AstroTortilla.  It works great and it's very tolerant of being able to run from a leisure battery.

 

The best part was that when I went into PC World, the sales staff there were completely lost when they tried to sell me a laptop.  I didn't know exactly what I wanted, but I knew that I didn't want expensive, and I knew that I didn't want rubbish.  They were struggling to answer any of my questions.  I wasn't being mean, it was questions like "can I see the power supply?", "how much RAM can I put into this machine total?".

 

Of course they were trying to sell me lots of "additions", which I turned down all of them.  They looked at my like I was an alien when I said it wasn't going to be attached to the internet (except to get official updates).   They were shocked when I said that I didn't want Office, or even a trial.  Then the best part was when they finally gave up trying to sell me stuff and asked me what I was going to use it for.  Should have seen their jaws drop when I said it was going to be controlling cameras and telescope for a portable obervatory (ok ok, slight exaggeration) Then when I pulled up my iPad and showed them some of my past images, their eye's popped out of their heads.

[Astrofriend]

Hi,

Thank you for posting your equipment. Maybe some people think that astronomers are odd people, or?

/Lars

[Gina]

I use a Raspberry Pi 3 to control my imaging rig and capture images.

[stash_old]

A point to remember is that you will really only do one or 2 Astro things together(well never really its not possible in Windows,Linux,IOS etc) and mostly 1 app is very light so having a I3 (which I use as well ?) is an over kill and I do Astrotoaster(so processing images) at the same time as guiding,Mount control ,plate solving and taking the next image (mind you with a DSLR its doing the work until I download an image).

Removing the Anti Virus checker - ok limit it and make it ignore certain folders which could be set to "read Only" - that really speeds up most PC's and networking - so if your Obsys is not internet connected do not run a virus checker - pointless as the updates wouldn't be up todate unless you transfer the files manual. If you transfer any files virus you should check them first before moving. 

Main 2 options that ,IMHO, are essential are Max Memory (3gb for 32bit,  8gb+ for 64gb) and a SSD - the later will speed up many older machines into very useful items.  You are only as fast as your slowest component!

Now if only the RPI had SATA interface by default and was reliable for Canon DSLR work ?

[russellhq]

You may also want to consider that newer machines are more power efficient than old ones and will throttle the CPU to only what's required.

I use stellarium to navigate around the sky and slew the telescope, though it's a bit of a resource hog. But recently I found out I can run stellarium on my laptop in the house and control my mount via WiFi through the pc that's connected to it outside and therefore lighten the load on the observatory pc. 

[Astrofriend]

Hi Gina,

You wrote that you use a Raspberry as astro computer. Is it Windows or Linux configured?

I was very curious about the Raspberry and what they can do. Did a test with a Linux setup, it worked as I want but with one problem. It was a bit slow, I think more RAM had solved the problem.

Here is a description of how I set it up:

http://www.astrofriend.eu/astronomy/projects/project-kstars-indi-linux/project-kstars-indi-linux.html

Later when there are faster and more powerfull Raspberrys I will start that project once again. I like it! With a simpler setup it should have worked without problem.

Lars

[kbrown]

+1 for raspberry pi. Was using 2 before but recently swapped it for 3 in a hunt for more power for planetary imaging (video streaming). I run the default raspbian Linux on it. 

[Gina]

I use Ubuntu MATE (Linux).  For faster image capture there's the Rock64 - much faster processor and USB3.  I haven't tried one yet.

[Robomort]

The Ras Pi is able to control the mount and camera because it acts only as the sever. Essentially communicating commands from a client (much more powerful computer running the user side programs like the planetarium/guider etc to the hardware via a protocol called Indi over wifi or ethernet. Think of Indi as the Linux equivalent of Ascom. Watch the vids below to get a sense of what is what and if The Pi is for you. USB3 would be nice but not really essential unless you want to do planetary work. For DSO imaging I can transfer a 24MPix image in far less time than any exposure you are likely to use.

 

 

[Astrofriend]

Hi,

I have it setup with all the software running on the Raspberry to have it independent of the communicating line. It will run even if the line goes down.

My Windows server is setup like that too and working very well even if the computer is slow with todays standard.

 

Here is the load on the Windows computer during different works:

http://astrofriend.eu/astronomy/tutorials/tutorial-cpu-load/tutorial-cpu-load.html

 

With the Linux and Raspberry I can of course divide the work among many Raspberries, but then it begins to be a bit complicated.

Lars