lkml.org 
[lkml]   [2017]   [Jul]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v8 1/1] f2fs: dax: implement direct access
On Wed, Jul 26, 2017 at 10:11:08AM -0700, Dan Williams wrote:
> Until HMAT came along we had no data in the kernel how to pick a sane
> default, but we could now very easily make a "if pmem performance <
> dram, disable dax by default" policy in the kernel.

I'd rather do it the other way around - if HMAT is present and
pmem performance >= dram use dax. Else require the explicit -o dax
for now to enable it. If an explicit -o nodax is specified disable
DAX even if HMAT says it is faster.

> The question for this patch is do we want to add yet another
> filesystem that adds "-o dax" or require use of per-inode flags to
> enable dax.

Please stick to the mount option. After spending a lot of time with
DAX and various memory techologies I'm pretty confident that the inode
flag is the wrong thing to do.

\
 
 \ /
  Last update: 2017-07-26 19:20    [W:0.080 / U:0.380 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site