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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: B0F45140019 X-Rspamd-Server: rspam09 X-Rspam-User: X-Stat-Signature: omin4sjg1x7heoyumniun8fkecc9s6gy X-HE-Tag: 1678313770-477564 X-HE-Meta: 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 oBBfEfvu sy4sAatdedsz1+R3OeopOrTclPW+tlbpN1ppCU4t799GFttrwIXSwakbY6I+OncOSxzTso0lyKcfqXRQ7FShWMfH/X0zLUToJl8YwMDnxwdzlq51u+Msp6ouuudC2l+/Mue9UP5Bjwj7vuw5cQwbwHoRCnAE8hTB1BS7dMxQd4YHJMNs7H1uMqX1U0nVzzDY71LzTGwyUzF8qYwk409i4Fq2ektT53EqaIhlLz3BDEQ1AM9xKnGvOPQRdj7hF4NXQYrb8RD3cTHJlQxyHA5jv4Nb/6MCSryfJr4egYc9Msd+NJURjAZU7cpNUY9aGLy2wIRL1U8aS2CUPoqNlhtL4Z6GBnCm5BzbSOPrRTdKxXOr8PhKFW3+2LviTlNjDb+gvbDPm X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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 > > --- > > 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