[systemd-devel] [PATCH v2] readahead: use BTRFS_IOC_DEFRAG_RANGE

[Andrey Borzenkov]

В Mon, 21 Jul 2014 16:51:22 +0300
Timofey Titovets <nefelim4ag at gmail.com> пишет:

> Zbyszek, thanks for comment, i will work on fixing what you say and
> resend patch.
> 
> >> Just completed TODO:
> >> * readahead: use BTRFS_IOC_DEFRAG_RANGE instead of BTRFS_IOC_DEFRAG
> >
> > This is still not an explanation. What is the difference between the
> > two?
> 
> I can't explain it, because no i add this todo in TODO list (recursively todo%)

I could not find any previous discussion on systemd list. TODO was
added by Lennart.

> >> -  - readahead: use BTRFS_IOC_DEFRAG_RANGE instead of BTRFS_IOC_DEFRAG ioctl, with START_IO
> But as i understand start_io option force write data, without
> buffering in memory, to the disk.
> may be it have a sacral sense, i ask for comments in btrfs list for
> explaration and add explanation to the v3
>