Skip to main content

linux - RAID setup for high speed reading



We are looking to build a realtime playback machine using Linux and a RAID (5 or 10) setup. The current setup looks like:




  • 12GB memory

  • 5 x 7200rpm drive (software raid)

  • centOS 6 (Kernel Linux 2.6.32-71.29.1.el6.x86_64)


  • NVidia Quadro 5000 (driver 280.13)

  • Intel(R) Xeon(R) CPU X5650 @ 2.67GHz



I did run Bonnie++ and iozone to do some benchmark with different raid setup (5 and 10), with
different fs type (ext4 and xfs), and different stripe size. Unfortunately it seems that I can't
get the speed I want out of it (always <200MB/s).



The other test I made was directly in the playback software (RV - http://www.tweaksoftware.com/products/rv), but could not get it to play faster than 20 frame per second (looking for 24 fps) with more than 3 sequences.




These playback details are a little futile, I just want to know what would be the best setup to get something like ~700MB/s read performance? Is it possible?



I've been reading quite a bit, seems like a hardware controller could be better. Also I guess 7200rpm is not enough. 10 or 15k might be better? What about SSD?



I've another constraint with this project, this machine will store all the sequences for all the projects, so density matter (I bet it will cost way more to get the same storage amount with SSD drives vs. std 10k rpm drive).



Any suggestions or tips will be appreciated to get the best read speed/storage amount.



Thanks!




Edit: Just stumble upon this http://www.fusionio.com/products/iodrive/. Anyone has experience with this card?


Answer



If you need to handle video streams then you got to get something way better than what you spec'd. Even if you get enough SATA drives to get the desired bandwidth of 700MB/s (which should be easily doable on todays consumer class hardware) you'll maybe have sever latency problems.



What good is your storage solution if you can crank out even 1GB/s but each IO takes 500ms or so to complete? You're talking video so you want something that can deliver enough IO so that your maximum latency of 40ms (25fps) for retrieving your frames is taken care of.



You might also want to have a look at specialized file systems for video streaming applications. Hitachi Data Systems (HDS) sells one for example also XFS does have an real-time extension that was developed for media applications.


Comments

Popular posts from this blog

iLO 3 Firmware Update (HP Proliant DL380 G7)

The iLO web interface allows me to upload a .bin file ( Obtain the firmware image (.bin) file from the Online ROM Flash Component for HP Integrated Lights-Out. ) The iLO web interface redirects me to a page in the HP support website ( http://www.hp.com/go/iLO ) where I am supposed to find this .bin firmware, but no luck for me. The support website is a mess and very slow, badly categorized and generally unusable. Where can I find this .bin file? The only related link I am able to find asks me about my server operating system (what does this have to do with the iLO?!) and lets me download an .iso with no .bin file And also a related question: what is the latest iLO 3 version? (for Proliant DL380 G7, not sure if the iLO is tied to the server model)

linux - Awstats - outputting stats for merged Access_logs only producing stats for one server's log

I've been attempting this for two weeks and I've accessed countless number of sites on this issue and it seems there is something I'm not getting here and I'm at a lost. I manged to figure out how to merge logs from two servers together. (Taking care to only merge the matching domains together) The logs from the first server span from 15 Dec 2012 to 8 April 2014 The logs from the second server span from 2 Mar 2014 to 9 April 2014 I was able to successfully merge them using the logresolvemerge.pl script simply enermerating each log and > out_putting_it_to_file Looking at the two logs from each server the format seems exactly the same. The problem I'm having is producing the stats page for the logs. The command I've boiled it down to is /usr/share/awstats/tools/awstats_buildstaticpages.pl -configdir=/home/User/Documents/conf/ -config=example.com awstatsprog=/usr/share/awstats/wwwroot/cgi-bin/awstats.pl dir=/home/User/Documents/parced -month=all -year=all...

linux - How can I get my mediawiki to stop thinking I have cookies disabled?

I've searched half a day for how to resolve this issue, and can't figure it out. Shortly after I made my wiki a simple private wiki according to the instructions at Mediawiki's website, it started giving me this weird login error message: Wiki uses cookies to log in users. You have cookies disabled. Please enable them and try again. If I remove those private wiki settings, the error disappears, even if I try logging in. But I need it to be a private wiki for only my team. So what do I do? Here's what I've done so far. Just to be safe, after ever change, I try rebooting Apache using: sudo /etc/init.d/apache2 restart In my php.ini file, I have the following set: session.save_path = "/var/lib/php5" session.cookie_secure = secure session.cookie_path = /tmp session.cookie_domain = my server's internal URL (should I even set this? this field was blank before, but not commented out) session.referer_check = Off I ran the following to ensure that the fold...