Results 1 to 7 of 7

Thread: Server spec - overkill?

  1. #1

    Question Server spec - overkill?

    Hi folks,

    We're developing a VOD solution for a local video distributor, and I'm a bit stumped on to the speccing out of the servers.

    Here's my current "dream" config:
    HP ProLiant ML350p Gen8
    2x Xeon E5-2620 (2GHz, 6 cores)
    32GB ECC RAM
    4 ports 1GbE in link aggregation (10GbE out of budget unfortunately)
    18x 2TB HDDs (to be arranged in sets of RAID0+1)

    The video we are streaming will be a maximum of 1280x720 at 5Mbps - this will be for VIP customers, otherwise the standard video is at 720x480, 1Mbps
    We expect maybe 30% of users to go for the HD option

    So, this means that to saturate the bandwidth, we could have a peak of about 3000 viewers

    No transcoding is required, all files will be pre-rendered in the appropriate sizes.

    So now my question is, am I seriously over-speccing the server? Or if were to buy 2 slowers ones at half the price, like this:
    HP ProLiant ML350p Gen8
    Xeon E5-2620 (2GHz, 6 cores)
    8GB ECC RAM

    Would this potentially be more efficient, in a load-balanced setup?

  2. #2
    Join Date
    Dec 2007
    Posts
    21,962

    Default

    Looks great to me. If it's more than enough, that is not a bad thing. You can't be too rich, thin or have to much ram, imo

    But, yes, if you were going to be putting together a large edge cluster you would have to look very carefully at cost/capacity and see what was most cost effective

    The 4gbs nic is perfect actually, Wowza/Java cannot saturate more than about 5gbs. So 10gbs nic would be under utilized unless you are able to run two instances of Wowza, which can be tricky.

    Richard

  3. #3

    Default

    Hi Richard,

    Thanks for your reply.

    In a nutshell, you are saying that total bandwidth is more important that CPU and RAM?

    Actually this brings me to a second question, about edge servers. if the project takes off, and in the future we were to have, for example, 10 or more edge servers (all with quad 1Gb LAN ports), how much of an extra load would this put on the origin server? In other words, could the origin server have the same specs as the edge servers? Can we get away with "weedy" edge servers since all they are doing is redirecting information?

    Sorry for the n00bish questions, I'm finding it hard to find concrete reference on this kind of setup

  4. Default

    Allow me to throw in a suggestion: look into using RAID-60 for your RAID setup instead of RAID-10 as it will give you a lot more available space. The downside is a small performance hit on writes, but I'm certain you're mostly dealing with reads, probably something like 80/20 read/write.

    Remember that you may have a bit of overhead, so instead of 4000mbps, you might be using around 3500mbps or less actual bandwidth.

    Another thing I would advise is to get more RAM. Disk is slow, RAM isn't. With a library that size you may want to look at 128GB of RAM, to have all the frequently requested content cached.

  5. #5

    Default

    Thanks, will look into that...

    So RAM caching is also possible? That could be interesting, I was playing with the idea of adding a couple of SSD drives (especially in the edge servers) for popular files, will have to see what would be more cost-effective

  6. #6

    Default

    1. If you can get 2 servers with the same bandwidth as your 1 server, I would get 2 servers. "Don't put all your eggs in 1 basket" and such...
    2. The OS will cache to RAM automatically. If you have only 100 VOD files all 1GB in size, then 128GBs of RAM should cache them all, and those files will be read from disk only on the first request. Subsequent requests will all be read from RAM, with the result being that your disk is not used (for those reads).

  7. #7

    Default

    OK, I'm still quite confused and would like to ask a few more Q's

    As well-explained above, the most important thing is IO bandwidth. Thus a good amount of RAM and SSD drives for the MediaCache system will be ideal.

    I'm just not sure about the CPU usage. Right now my test server (i7 920) is running with negligible CPU and RAM usage, but that's with maybe 10 connected viewers, I am aiming to saturate the bandwidth of 4x 1Gbps adapters.

    The only kind of solid reference I can find is here:
    http://www.wmconsulting.info/wowza-c...reaming-sites/
    But this is pretty old, and related to live streaming, not VOD.

    I guess what I am asking this, in order for the CPU to not be a bottleneck with a maxed out 4Gbps, what is the minimum CPU spec I should be getting? Cost is a bit of an issue, I'd much rather be able to get 2 servers for the price of one top-class one, as long as they don't get overloaded...

Similar Threads

  1. Playlist stream source spec
    By Atmapuri in forum Wowza Streaming Server Java API
    Replies: 5
    Last Post: 07-21-2014, 01:06 PM
  2. Server Spec
    By amsl68 in forum General Forum
    Replies: 3
    Last Post: 08-07-2013, 05:13 AM
  3. Encoders Spec & Design
    By azrilnazli in forum General Forum
    Replies: 1
    Last Post: 08-23-2012, 05:10 AM
  4. Server Spec?
    By Jackster in forum Server Administration Discussion
    Replies: 3
    Last Post: 05-29-2012, 07:01 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •