Re: [PATCH 07/19] btrfs: do sequential extent allocation in HMZONED mode

From: David Sterba
Date: Thu Jun 27 2019 - 11:28:11 EST


On Tue, Jun 18, 2019 at 08:49:00AM +0000, Naohiro Aota wrote:
> On 2019/06/18 7:29, David Sterba wrote:
> > On Fri, Jun 07, 2019 at 10:10:13PM +0900, Naohiro Aota wrote:
> >> + u64 unusable;
> >
> > 'unusable' is specific to the zones, so 'zone_unusable' would make it
> > clear. The terminilogy around space is confusing already (we have
> > unused, free, reserved, allocated, slack).
>
> Sure. I will change the name.
>
> Or, is it better toadd new struct "btrfs_seq_alloc_info" and move all
> these variable there? Then, I can just add one pointer to the struct here.

There are 4 new members, but the block group structure is large already
(528 bytes) so adding a few more will not make the allocations worse.
There are also holes or inefficient types used so the size can be
squeezed a bit, but this is unrelated to this patchset.