Re: [PATCH 4/4] f2fs: avoid frequent checkpoint during f2fs_gc

From: Jaegeuk Kim
Date: Tue Apr 11 2017 - 18:14:18 EST


On 04/11, Chao Yu wrote:
> On 2017/4/11 8:13, Jaegeuk Kim wrote:
> > Now we're doing SSR aggressively more than ever before, so once we reach to
> > the reserved_segment, f2fs_balance_fs will call f2fs_gc, which triggers
> > checkpoint everytime. We actually must avoid that.
> >
> > Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> > ---
> > fs/f2fs/gc.c | 6 +++++-
> > 1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> > index e2f9b2b12b74..4a720f3394d9 100644
> > --- a/fs/f2fs/gc.c
> > +++ b/fs/f2fs/gc.c
> > @@ -966,7 +966,11 @@ int f2fs_gc(struct f2fs_sb_info *sbi, bool sync, bool background)
> > * threshold, we can make them free by checkpoint. Then, we
> > * secure free segments which doesn't need fggc any more.
> > */
> > - ret = write_checkpoint(sbi, &cpc);
> > + if (prefree_segments(sbi)) {
> > + ret = write_checkpoint(sbi, &cpc);
> > + if (ret)
> > + goto stop;
> > + }
> > if (ret)
> > goto stop;
>
> We don't need redundant check here?

Yup, will remove this. ;)

>
> Otherwise, this patchset looks good to me, anyway please add:
>
> Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>

Thanks,

>
> Thanks,
>
> > if (has_not_enough_free_secs(sbi, 0, 0))
> >