On Mon, Mar 06, 2023 at 03:04:57PM +0100, David Hildenbrand wrote: > On 03.03.23 00:27, Luis Chamberlain wrote: > > Update the docs to reflect a bit better why some folks prefer tmpfs > > over ramfs and clarify a bit more about the difference between brd > > ramdisks. > > > > Signed-off-by: Luis Chamberlain <mcgrof@xxxxxxxxxx> > > --- > > Documentation/filesystems/tmpfs.rst | 27 +++++++++++++++++++-------- > > 1 file changed, 19 insertions(+), 8 deletions(-) > > > > diff --git a/Documentation/filesystems/tmpfs.rst b/Documentation/filesystems/tmpfs.rst > > index 0408c245785e..e77ebdacadd0 100644 > > --- a/Documentation/filesystems/tmpfs.rst > > +++ b/Documentation/filesystems/tmpfs.rst > > @@ -13,14 +13,25 @@ everything stored therein is lost. > > tmpfs puts everything into the kernel internal caches and grows and > > shrinks to accommodate the files it contains and is able to swap > > -unneeded pages out to swap space. It has maximum size limits which can > > -be adjusted on the fly via 'mount -o remount ...' > > - > > -If you compare it to ramfs (which was the template to create tmpfs) > > -you gain swapping and limit checking. Another similar thing is the RAM > > -disk (/dev/ram*), which simulates a fixed size hard disk in physical > > -RAM, where you have to create an ordinary filesystem on top. Ramdisks > > -cannot swap and you do not have the possibility to resize them. > > +unneeded pages out to swap space. > > I suppose, in contrast to ramfs, tmpfs also supports THP. Maybe worth adding > as well. Good call, both the mount and the sysfs file (which is registered by THP) lacks any documentation so I'll just add docs for both. Luis
