Re: Re: File system defragmentation. Something that can resume after stopping.

Javier Martinez <[email protected]> Thu, 14 May 2026 18:38:09 +0200
Newsgroups gmane.linux.gentoo.user
Message-ID <[email protected]>
El 14/5/26 a las 18:18, Holger Hoffstätte escribió:
> On 2026-05-14 12:30, Michael wrote:
>> There's this archived paper from a 2007 Linux Symposium which explains 
>> how
>> linux filesystems intelligently delay writing data to disk until the last
>> moment so that data is allocated as contiguously as possible.  Also, 
>> after a
> 
> That (delalloc) is unfortunately not even half the story. XFS is still 
> the only
> filesystem (on Linux) that does persistent preallocation on regular writes,
> and splitting the filesystem into multiple AGs (allocation groups) is 
> much more
> effective for *long-term* mixed-size free-space management than whatever 
> ext4
> does even today.
> 
> So while we're posting papers:
> https://www.usenix.org/conference/hotstorage19/presentation/conway
> 
> Enjoy :)
> 
> -h
> 

Without light everyone are like the others... so...
If you have your disks almost full, no filesystem will rescue you from 
fragmentation.
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