Re: [PATCH 1/2] fs: add FMODE_DIO_PARALLEL_WRITE flag

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Fri, Apr 14, 2023 at 08:36:12AM -0700, Darrick J. Wong wrote:
> IIUC uring wants to avoid the situation where someone sends 300 writes
> to the same file, all of which end up in background workers, and all of
> which then contend on exclusive i_rwsem.  Hence it has some hashing
> scheme that executes io requests serially if they hash to the same value
> (which iirc is the inode number?) to prevent resource waste.
> 
> This flag turns off that hashing behavior on the assumption that each of
> those 300 writes won't serialize on the other 299 writes, hence it's ok
> to start up 300 workers.
> 
> (apologies for precoffee garbled response)

It might be useful if someone (Jens?) could clearly document the
assumptions for this flag.



[Index of Archives]     [Linux Ext4 Filesystem]     [Union Filesystem]     [Filesystem Testing]     [Ceph Users]     [Ecryptfs]     [NTFS 3]     [AutoFS]     [Kernel Newbies]     [Share Photos]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux Cachefs]     [Reiser Filesystem]     [Linux RAID]     [NTFS 3]     [Samba]     [Device Mapper]     [CEPH Development]

  Powered by Linux