Re: Direct I/O

On Sun, Apr 9, 2023 at 11:25 PM Andrew Dunstan <andrew@dunslane.net> wrote:

Didn't seem to make any difference.

Thanks for testing.  I think it's COW (and I think that implies also
checksums?) that needs to be turned off, at least based on experiments
here.

Googling agrees with you about checksums.  But I'm still wondering if we shouldn't disable COW for the build directory etc. It is suggested at [1]:

Recommend to set nodatacow – turn cow off – for the files that require fast IO and tend to get very big and get alot of random writes: such VMDK (vm disks) files and the like.

I'll give it a whirl.

cheers

andrew

[1] <http://www.infotinks.com/btrfs-disabling-cow-file-directory-nodatacow/>

--
Andrew Dunstan
EDB: https://www.enterprisedb.com