>> ------------------------------------------------------------------------
>> On Sep 15, 2014 7:24 PM, ToddAndMargo <[log in to unmask]> wrote:
>>
>>  >> On Sep 15, 2014 7:07 PM, ToddAndMargo <[log in to unmask]> wrote:
>>  >>
>>  >> Hi All,
>>  >>
>>  >> I have a customer whose with a long term project which
>>  >> includes about 30 IP cameras. He wants to both view and
>>  >> record. Anyone know or have a favorite Linux server
>>  >> for such?
>>  >>
>>  >> Many thanks,
>>  >> -T
>>  >>
>>
>> On 09/15/2014 04:17 PM, Paul Robert Marino wrote:
>>  > Look at the ones that specialize as a DVR there are a few of them but
>>  > off the top of my head I can't remember the name of the software
>>  > involved. But there are a few distros that specialize in this. A warning
>>  > though with that many feed you will probably need a hefty RAID which may
>>  > need an external disk enclosure at the least just to get the bandwidth
>>  > from striping across a sufficient number of spindals and SSD's won't
>> help.
>>
>> Hi Paul,
>> What is your technical opinion of SATA vs SAS in this
>> type of application (tons of data constantly flowing)?
>>
>> -T

On 09/15/2014 04:58 PM, Paul Robert Marino wrote:
> There is surprisingly little difference between the two. The primary
> difference is SAS controllers then to be better and the stats on the
> disk themselves tend to be more honest.
>
> when talking about SATA the real question is are you talking about
> standard retain or nearline.
>
>   Retail sata drives stats are based on inherine instability at the
> write cache layer and burst rates based on the cache used as a write
> buffer. An fsync on a retail sata drive lies to youand says its complete
> when it hits the write cache. Nearline is honest about fsyncs.
>
> Sas is honest across the board and they tend to be higher production
> quality drives with lower failure rates and run at higher rpm's and
> therefore are faster.
> That said if you compare a nearline SATA and a SAS disk at the same
> number of RPM's you get relatively the same performance but the SATA
> drive is cheaper.
>
> That said it comes down to service contracts with manufacturers. If you
> don't intend to have one SAS definitely pays off. If you have a good
> service contract and all other specs, all other specs are equal and you
> don't mind swapping out disks more often SATA nearline is the way to go.
>
>
> -- Sent from my HP Pre3
>

Hi Paul,

Somewhere in the back of my memory I remember that SAS could do
multiple reads and writes on a single pass.

-T