On Tue, Aug 25, 2015 at 05:45:53PM +0800, Chao Yu wrote: > > -----Original Message----- > > From: Chao Yu [mailto:chao2...@samsung.com] > > Sent: Tuesday, August 25, 2015 5:34 PM > > To: 'Jaegeuk Kim' > > Cc: linux-kernel@vger.kernel.org; linux-f2fs-de...@lists.sourceforge.net > > Subject: Re: [f2fs-dev] [PATCH 9/9] f2fs: update extent tree in batches > > > > > -----Original Message----- > > > From: Chao Yu [mailto:chao2...@samsung.com] > > > Sent: Friday, August 21, 2015 8:55 PM > > > To: 'Jaegeuk Kim' > > > Cc: linux-kernel@vger.kernel.org; linux-f2fs-de...@lists.sourceforge.net > > > Subject: Re: [f2fs-dev] [PATCH 9/9] f2fs: update extent tree in batches > > > > > > Hi Jaegeuk, > > > > > > > -----Original Message----- > > > > From: Jaegeuk Kim [mailto:jaeg...@kernel.org] > > > > Sent: Friday, August 21, 2015 1:48 AM > > > > To: Chao Yu > > > > Cc: linux-f2fs-de...@lists.sourceforge.net; linux-kernel@vger.kernel.org > > > > Subject: Re: [PATCH 9/9] f2fs: update extent tree in batches > > > > > > > > Hi Chao, > > > > > > > > On Wed, Aug 19, 2015 at 07:21:48PM +0800, Chao Yu wrote: > > > > > This patch introduce a new helper f2fs_update_extent_tree_range > > > > > which can update extent nodes in extent tree in batches. > > > > > > > > > > Now, we use the function to invalidate blocks in batches instead of > > > > > invalidating them one by one when truncating blocks. > > > > > > > > IMO, it's not clear the benefit of this patch in terms of performance > > > > and code > > > > readability versus risky code changes. > > > > > > This is only used in truncate path, IMO, in theory, we can gain benefit > > > from > > > this batch mode operation when truncating frequently. > > > > > > I will test the patch for numbers. > > > > Since in batched operation is only used in truncation path, I only stat data > > in that path. And I add below function to test for stating time count. > > > > uint64_t rdtsc(void) > > { > > uint32_t lo, hi; > > __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi)); > > return (uint64_t)hi << 32 | lo; > > } > > > > My test environment is: ubuntu, intel i7-3770, 16G memory, 256g micron ssd. > > > > Sorry, it's out of format. > > a) Removing 128MB file which has one extent node mapping whole range of file: > 1. dd if=/dev/zero of=/mnt/f2fs/128M bs=1M count=128 > 2. sync > 3. rm /mnt/f2fs/128M > count total average > f2fs_update_extent_tree_range 33 3321 100.63 > f2fs_update_extent_cache 32768 7651022 233.49 > > b) fsstress: > fsstress -d /mnt/f2fs -l 5 -n 100 -p 20 > count total average > f2fs_update_extent_tree_range 1868 1073762 574.82 > f2fs_update_extent_cache 31518 11495827 364.74
So, the remaining concern is risky big code changes. Let me take time to review and test this for a while. Thank you for the work. :) Thanks, -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
