On 2015/9/9 9:11, Chao Yu wrote: >> -----Original Message----- >> From: He YunLei [mailto:[email protected]] >> Sent: Wednesday, September 09, 2015 7:54 AM >> To: Chao Yu >> Cc: [email protected]; [email protected]; >> [email protected] >> Subject: Re: [f2fs-dev] [PATCH] f2fs: add a judgment in add_discard_addrs >> >> On 2015/9/8 19:14, Chao Yu wrote: >>> Hi Yunlei, >>> >>>> -----Original Message----- >>>> From: Yunlei He [mailto:[email protected]] >>>> Sent: Tuesday, September 08, 2015 6:51 PM >>>> To: [email protected]; [email protected]; >>>> [email protected] >>>> Cc: [email protected]; Yunlei He >>>> Subject: [f2fs-dev] [PATCH] f2fs: add a judgment in add_discard_addrs >>>> >>>> CP_DISCARD traverse all segments in fstrim_range to add small discards, >>>> it is better to select entry->len bigger than trim_minlen. >>> >>> If we mount with 'discard' option, f2fs will trigger real-time discard >>> when do checkpoint. If we add judgment condition here, fragmented invalid >>> blocks will not be discarded since we stop adding them in pending list >>> through __add_discard_entry. >> >> This judgment condition is only valid for cp reason CP_DISCARD, and has no >> influence >> to other checkpoint. The process of fstrim adds all invalid blocks in >> pending list and >> deletes entries which len < trim_minlen when issue discard. Can we do the >> selection >> when added? > > __add_discard_entry will try to merge small discards in pending list, and > merged discard > may be the eligible candidate, so we'd better not skip that. > Yeah, I got it. But I think the probability of merge will not be too high. Thanks, > Thanks, > >> >> Thanks, >> >>> >>> Thanks, >>> >>>> >>>> Signed-off-by: Yunlei He <[email protected]> >>>> --- >>>> fs/f2fs/segment.c | 3 ++- >>>> 1 file changed, 2 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c >>>> index 78e6d06..a0dab7a 100644 >>>> --- a/fs/f2fs/segment.c >>>> +++ b/fs/f2fs/segment.c >>>> @@ -599,7 +599,8 @@ static void add_discard_addrs(struct f2fs_sb_info >>>> *sbi, struct cp_control >>>> *cpc) >>>> break; >>>> >>>> end = __find_rev_next_zero_bit(dmap, max_blocks, start >>>> + 1); >>>> - __add_discard_entry(sbi, cpc, se, start, end); >>>> + if(force && cpc->trim_minlen >= (end - start)) >>>> + __add_discard_entry(sbi, cpc, se, start, end); >>>> } >>>> } >>>> >>>> -- >>>> 1.9.1 >>> >>> >>> > > > . >
------------------------------------------------------------------------------ Monitor Your Dynamic Infrastructure at Any Scale With Datadog! Get real-time metrics from all of your servers, apps and tools in one place. SourceForge users - Click here to start your Free Trial of Datadog now! http://pubads.g.doubleclick.net/gampad/clk?id=241902991&iu=/4140 _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
