Messages in this thread | | | Date | Mon, 16 Aug 2021 17:16:24 -0700 | From | Jaegeuk Kim <> | Subject | Re: [PATCH 1/2] f2fs: add sysfs nodes to get discard information |
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On 08/16, 李扬韬 wrote: > >>>> I've added new sysfs nodes to show discard stat since mount, which > >>>> will help us analyze whether the performance problem is related to > >>>> discard. > >>>> > >>>> issued_discard - Shows the number of issued discard > >>>> queued_discard - Shows the number of cached discard cmd count > >>>> discard_cmd_cnt - Shows the number of cached discard cmd count > >>>> undiscard_blks - Shows the number of undiscard blocks > >>> > >>> We have exported them in debugfs, can you use that? > >>> > >>> Thanks, > >> > >> But now Android is forbidden to open debugfs, and in fact we have not > >> opened this configuration for a long time. > > > >Weren't them be used for debug purpose? can you please explain more about > >your use case? > > During long-term aging test or normal use, sometimes there will be performance > degradation problems. It may be caused by storage, or it may be caused by the > filesystem. For example, the filesystem accumulates a large number of undiscard > blocks. Although there is some remaining space, the androidbench test will > show performance degradation. Therefore, it is necessary to export information > related to discard so that we can confirm this situation.
I think you can mount debugfs for that case?
> > Thx, > >
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