Softupdates a mount option?

Ivan Voras ivoras at fer.hr
Thu May 27 08:50:20 PDT 2004


Bernd Walter wrote:

>>>SU makes perfectly sense for swap backed md drives.
>>
>>I always thought the "swap backed" meant the memory is allocated from the 
>>same pool as for userland applications, e.g. they only get swapped out if 
>>memory is scarce. Is this wrong?
> 
> 
> You are right, but md(4) doesn't know about the filesystem and therefor
> can't know which blocks have content to keep and which are unused.
> SU now allows files that are deleted quite fast to never touch the
> block device and md never need to write those blocks into swap storage
> as they never got dirty.

As opposed to the 'async' mode?


-- 
Every sufficiently advanced magic is indistinguishable from technology
    - Arthur C Anticlarke



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