|| ||Artem Bityutskiy <Artem.Bityutskiy@nokia.com> |
|| ||Linux Kernel Mailing List <firstname.lastname@example.org> |
|| ||EXT4-ish "fixes" in UBIFS |
|| ||Fri, 27 Mar 2009 14:48:10 +0200|
|| ||Article, Thread
UBIFS has exactly the same properties like ext4 - in case
of power cuts:
1. truncate/write/close leads to empty files
2. create/write/rename leads to empty files
UBIFS is used in hand-held and and power-cuts are very
often there, because users just remove battery often.
I realize the "reality is different" argument, and already
concluded that we need a similar changes as Theo has done
We have a problem that user-space people do not want to
use 'fsync()', even when they are pointed to their code
which is doing create/write/rename/close without fsync().
They just say - this is file-system bug, it is fixed in
ext4 now, just fix the bug in UBIFS.
I tell them, that is not a fix, that is band-aid, because
ext4 issues asynchronous write, and a power cut can lead
to corruptions anyway.
I tell them, we can make this in UBIFS, but please, anyway
add fsync() to your application. They say - now, we will
will not - you fix your UBIFS.
And because there is so much flood and about this, it is
so difficult to have reasonable arguments. I want to say
people - please, still use fsync(), if this is about the
performance/reliability trade-off - make it optional.
But they instead say - respected people are on our side,
go away. And point me this:
And they say that BTRFS and XFS are going to fix userspace
as well, and point me at this:
This all became so messy and controversial. What should I do
to persuade userspace to use 'fsync()' even if we hack UBIFS
similarly to ext4? Suggestions?
Artem Bityutskiy (????? ????????)