: lustre-discuss on behalf of
Andreas Dilger via lustre-discuss
Sent: 29 April 2024 19:29
To: Simon Guilbault
Cc: lustre-discuss@lists.lustre.org
Subject: Re: [lustre-discuss] [EXTERNAL] [BULK] Files created in append mode
don't obey directory default stripe count
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Subject: Re: [lustre-discuss] [EXTERNAL] [BULK] Files created in append mode
don't obey directory default stripe count
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Simon is exactly correct. This is expected behavior for files opened with
O_APPEND, at least until LU-12738 is implemented. Since O_APPEND writes are
(by definition) entirely serialized, having multiple stripes on such files is
mostly useless and just adds overhead.
Feel free to read
This is the expected behaviour. In the original implementation of PFL, when
a file was open in append mode, the lock from 0 to EOF was initializing all
stripes of the PFL file. We have a PFL layout on our system with 1 stripe
up to 1 GB, then it increased to 4 and then 32 stripes when the file was
Wow, I would say that is definitely not expected. I can recreate this on both
of our LFS’s. One is community lustre 2.14, the other is a DDN Exascalar.
Shown below is our community lustre but we also have a 3-segment PFL on our
Exascalar and the behavor is the same there.
$ echo > aaa
$
