From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jaegeuk Kim Subject: Re: [PATCH 1/2] f2fs: replace __get_victim by dirty_segments in FG_GC Date: Fri, 17 Feb 2017 11:15:04 -0800 Message-ID: <20170217191504.GC2951@jaegeuk.local> References: <20170217091639.29433-1-heyunlei@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1cenzv-000096-L1 for linux-f2fs-devel@lists.sourceforge.net; Fri, 17 Feb 2017 19:15:15 +0000 Received: from mail.kernel.org ([198.145.29.136]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.76) id 1cenzt-0006mr-E8 for linux-f2fs-devel@lists.sourceforge.net; Fri, 17 Feb 2017 19:15:15 +0000 Content-Disposition: inline In-Reply-To: <20170217091639.29433-1-heyunlei@huawei.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net To: Yunlei He Cc: linux-f2fs-devel@lists.sourceforge.net Hi Yunlei, I also removed "segno = NULL_SEGNO;" in the beginning part near gc_more. Thanks, On 02/17, Yunlei He wrote: > In FG_GC process, it will search victim section twice. This will > cause some dirty section with less valid blocks skip garbage > collection. > > section # 26425 : valid blocks # 3 > 142.037567: get_victim_by_default: victim 26425 : valid blocks # 3 > 142.037585: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26425 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 244 > 142.039494: f2fs_get_victim: dev = (259,30), type = Hot DATA, policy = (Background GC, SSR-mode, Greedy), victim = 19022 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 24 > 142.070247: new_curseg: Debug: alloc new segment 26746 > 142.244341: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26054 ofs_unit = 1, pre_victim_secno = 26054, prefree = 0, free = 243 > 142.254475: do_garbage_collect: Debug: FG_GC, seg_freed = 1 > 142.293131: f2fs_get_victim: dev = (259,30), type = Warm DATA, policy = (Background GC, SSR-mode, Greedy), victim = 23466 ofs_unit = 1, pre_victim_secno = -1, prefree = 0, free = 244 > 142.319001: f2fs_get_victim: dev = (259,30), type = Warm DATA, policy = (Background GC, SSR-mode, Greedy), victim = 23467 ofs_unit = 1, pre_victim_secno = -1, prefree = 0, free = 244 > 142.368879: get_victim_by_default: victim 26425 : valid blocks # 3 > 142.368894: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26425 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 244 > 142.378127: f2fs_get_victim: dev = (259,30), type = Hot DATA, policy = (Background GC, SSR-mode, Greedy), victim = 19612 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 24 > 142.416917: new_curseg: Debug: alloc new segment 26054 > 142.656794: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 25404 ofs_unit = 1, pre_victim_secno = 25404, prefree = 0, free = 243 > 142.662139: do_garbage_collect: Debug: FG_GC, seg_freed = 1 > 142.684159: new_curseg: Debug: alloc new segment 25197 > 142.685059: get_victim_by_default: victim 26425 : valid blocks # 3 > 142.685079: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26425 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 243 > 142.701427: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26238 ofs_unit = 1, pre_victim_secno = 26238, prefree = 0, free = 243 > 142.707105: do_garbage_collect: Debug: FG_GC, seg_freed = 1 > 142.802444: f2fs_get_victim: dev = (259,30), type = Warm DATA, policy = (Background GC, SSR-mode, Greedy), victim = 23473 ofs_unit = 1, pre_victim_secno = -1, prefree = 0, free = 244 > 142.804422: get_victim_by_default: victim 26425 : valid blocks # 3 > 142.804443: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26425 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 244 > 142.851567: f2fs_get_victim: dev = (259,30), type = Hot DATA, policy = (Background GC, SSR-mode, Greedy), victim = 19092 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 24 > 142.865014: new_curseg: Debug: alloc new segment 26238 > 143.082245: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26307 ofs_unit = 1, pre_victim_secno = 26307, prefree = 0, free = 244 > 143.088252: do_garbage_collect: Debug: FG_GC, seg_freed = 1 > 143.128307: new_curseg: Debug: alloc new segment 25404 > 143.181846: get_victim_by_default: victim 26425 : valid blocks # 3 > 143.181872: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26425 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 244 > > Signed-off-by: Yunlei He > --- > fs/f2fs/gc.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c > index 88e5e7b..74e1553 100644 > --- a/fs/f2fs/gc.c > +++ b/fs/f2fs/gc.c > @@ -943,12 +943,10 @@ int f2fs_gc(struct f2fs_sb_info *sbi, bool sync, bool background) > * enough free sections, we should flush dent/node blocks and do > * garbage collections. > */ > - if (__get_victim(sbi, &segno, gc_type) || > - prefree_segments(sbi)) { > + if (dirty_segments(sbi) || prefree_segments(sbi)) { > ret = write_checkpoint(sbi, &cpc); > if (ret) > goto stop; > - segno = NULL_SEGNO; > } else if (has_not_enough_free_secs(sbi, 0, 0)) { > ret = write_checkpoint(sbi, &cpc); > if (ret) > @@ -959,7 +957,7 @@ int f2fs_gc(struct f2fs_sb_info *sbi, bool sync, bool background) > goto stop; > } > > - if (segno == NULL_SEGNO && !__get_victim(sbi, &segno, gc_type)) > + if (!__get_victim(sbi, &segno, gc_type)) > goto stop; > ret = 0; > > -- > 2.10.1 ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot