<story><title>What’s New in Apple Filesystems [pdf]</title><url>https://devstreaming-cdn.apple.com/videos/wwdc/2019/710aunvynji5emrl/710/710_whats_new_in_apple_file_systems.pdf</url></story><parent_chain><item><author>jandrese</author><text>My understanding is that deduplication has generally been not worth the effort for a general use filesystem.  The cost in memory, cpu, and sheer complexity doesn&amp;#x27;t pay off in enough storage savings.  Disk space is relatively cheap.  Filesystem crashes&amp;#x2F;corruption are not.</text></item><item><author>vardump</author><text>So containers with a new bi-directional hardlink &amp;quot;Firmlink&amp;quot; (intended to be invisible to applications, link between encrypted containers), with read only volumes protecting system software.&lt;p&gt;ZFS send&amp;#x2F;receive style volume serialization for replication backup, etc. File system snapshot support included.&lt;p&gt;iOS or should I say iPadOS supports external USB media and SMB.&lt;p&gt;What seems to be missing is block level checksumming and integrity checks, scrubbing, block level duplication to protect important files, etc. No whiff of deduplication either, but that might be too memory intensive for Apple&amp;#x27;s purposes.</text></item></parent_chain><comment><author>vardump</author><text>Yeah, block level deduplication is not useful for files on a typical consumer laptop. I can imagine it&amp;#x27;s even less useful for files on iOS devices.&lt;p&gt;However it is often great for virtual machines and other software development related things, as long as all the underlying block sizes and alignments match.&lt;p&gt;You really do want strong integrity guarantees though. One corrupted block can cause a lot of damage.</text></comment>
<story><title>What’s New in Apple Filesystems [pdf]</title><url>https://devstreaming-cdn.apple.com/videos/wwdc/2019/710aunvynji5emrl/710/710_whats_new_in_apple_file_systems.pdf</url></story><parent_chain><item><author>jandrese</author><text>My understanding is that deduplication has generally been not worth the effort for a general use filesystem.  The cost in memory, cpu, and sheer complexity doesn&amp;#x27;t pay off in enough storage savings.  Disk space is relatively cheap.  Filesystem crashes&amp;#x2F;corruption are not.</text></item><item><author>vardump</author><text>So containers with a new bi-directional hardlink &amp;quot;Firmlink&amp;quot; (intended to be invisible to applications, link between encrypted containers), with read only volumes protecting system software.&lt;p&gt;ZFS send&amp;#x2F;receive style volume serialization for replication backup, etc. File system snapshot support included.&lt;p&gt;iOS or should I say iPadOS supports external USB media and SMB.&lt;p&gt;What seems to be missing is block level checksumming and integrity checks, scrubbing, block level duplication to protect important files, etc. No whiff of deduplication either, but that might be too memory intensive for Apple&amp;#x27;s purposes.</text></item></parent_chain><comment><author>FPGAhacker</author><text>Disk space isn’t cheap on a Mac laptop.</text></comment>