[mythtv-users] An SSD for Backend OS / Database Drives?

[Andre]

On 14 Mar 2012, at 22:29, tortise wrote:

> My Server's OS/Database HDD is possibly showing signs of aging being an 
> older and noisier 7200 120G that's got a few bad sectors reallocated.
> 
> Having found SSD on frontends give a significant user speed upgrade 
> (faster on/off and faster menu responses) I am now considering replacing 
> the backend OS drive with an SSD. (Also 3 x 2TB drives for recordings 
> seem happy there)
> 
> Some of the new 6G series 3 SSD's such as the Adata S510's seem a 
> possible replacement, capable of 550/510MB read and write speeds.
> 
> My motherboard (Gigabyte GA-EP31-DS3L)is a SATA 2 which I understand to 
> mean it can transfer 3Gb/s over the SATA interface.
> 
> There seems little point in spending extra on SDD's that run faster than 
> the SATA II interface, unless there is no disadvantage...
> 
> The b and B's might be confused somewhere, however it seems the full 
> 550/510MB read and writes may be available on the SATA II interface.
> 
> If one uses a SSD on a backend (no frontend use) then the only 
> difference I expect I am going to see is faster mythweb page loads, 
> which might be nice for the recordings page.  The frontend recordings 
> lists might also populate quicker.  This basically assumes the database 
> reads are read from the disc and not from RAM, my understanding is its 
> done from the disc, if so there seems considerable scope for speeding up 
> the user experience that relies on the myriad of reads?
> 
> Can anyone comment about this analysis, do you agree or see it 
> differently?  I presume some people have now done this, what has been 
> their experience?

I have an SSD an "old" "slow" Intel 120GB, as / /var & /home I find mythweb page refresh to be as good as instantaneous (with 6TB of HD recordings), database is significantly faster re-schedules are almost instant. Opening the recordings screen in Arclight is fast, a second or so, before it was ~30s before anything could be done.

I also have a diskless frontend netbooting from the SSD and this seems to make no difference to performance of the backend, before when the frontend was booted from a magnetic disk there was some slowdown when the frontend was running.

I find I must run disktrim manually every few weeks to keep performance high, I believe that Ubuntu 10.10 doesn't support background trim directly.

I'm running 0.24 on Ubuntu 10.10 64 bit, netbooted FE is 10.10 32bit, at the time Nvidia drivers were not good for 64bit and a GT430.

I don't think you need a large SSD, mine is mostly empty, 80GB or even 40GB at a squeeze would be ok. I keep the fanart etc on SSD too, seems to prevent a lot of seeking on the recordings drives.

Wouldn't have a Laptop, Desktop or Server without an SSD now. 

Andre