[mythtv-users] EXT4 vs XFS

[Robin Hill]

On Thu Nov 17, 2011 at 12:59:02 -0500, Mark Lord wrote:

> On 11-11-17 05:24 AM, phipps-hutton at sky.com wrote:
> >
> > Wear and tear:
> > TRIM support means that the kernel tells the drive controller that a  
> > sector is unused and the kernel will not expect the sector contents to  
> > be preserved. That's all it does. SSD controllers use this information  
> > to erase the sectors and put them on the list of erased sectors. They  
> > do this when they have nothing to do and they maintain the list in  
> > permanent storage...
> ..
> 
> That's certainly a good guess at what happens, and it's exactly what
> just about all of us expected.  Until some of us actually tried it
> and measured things.
> 
> Most SSDs (but not all) perform immedate erase cycles in response to TRIM,
> and those are done synchronously (blocking other I/O until done).
> 
TRIM is also a non-queueable command, requiring a complete flush of the
command queue before the TRIM command can be sent,

Cheers,
    Robin
-- 
     ___        
    ( ' }     |       Robin Hill        <myth at robinhill.me.uk>  |
   / / )      | Little Jim says ....                            |
  // !!       |      "He fallen in de water !!"                 |
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