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Subject: Re: File system for scratch space (in HPC cluster)
To:     "Theodore Y. Ts'o" <tytso@mit.edu>,
        Paul Menzel <pmenzel@molgen.mpg.de>
Cc:     linux-fsdevel@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Donald Buczek <buczek@molgen.mpg.de>
References: <e143071a-b1dc-56a4-a82e-865bae4c60c1@molgen.mpg.de>
 <20191024145504.GD1124@mit.edu>
From:   Boaz Harrosh <openosd@gmail.com>
Message-ID: <70755c40-b800-8ba0-a0df-4206f6b8c8d4@gmail.com>
Date:   Thu, 24 Oct 2019 18:01:05 +0300
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On 24/10/2019 17:55, Theodore Y. Ts'o wrote:
> On Thu, Oct 24, 2019 at 12:43:40PM +0200, Paul Menzel wrote:
>>
>> In our cluster, we offer scratch space for temporary files. As
>> these files are temporary, we do not need any safety
>> requirements – especially not those when the system crashes or
>> shuts down. So no `sync` is for example needed.
>>
>> Are there file systems catering to this need? I couldn’t find
>> any? Maybe I missed some options for existing file systems.
> 
> You could use ext4 in nojournal mode.  If you want to make sure that
> fsync() doesn't force a cache flush, you can mount with the nobarrier
> mount option.
> 

And open the file with O_TMPFILE|O_EXCL so there is no metadata as well.

I think xfs for O_TMPFILE|O_EXCL does not do any fsync, but I'm
not sure

> 					- Ted
>