On Fri, Mar 18, 2022 at 10:28:44AM +0100, Pankaj Raghav wrote: > > > On 2022-03-18 08:54, Naohiro Aota wrote: > >> > >> -zonesize=$(cat /sys/block/$(_short_dev $SCRATCH_DEV)/queue/chunk_sectors) > >> -zonesize=$((zonesize << 9)) > >> - > >> _scratch_mkfs >/dev/null 2>&1 > >> _scratch_mount -o commit=1 # 1s commit time to speed up test > >> > >> @@ -49,12 +46,18 @@ if [[ "$uuid" == "" ]]; then > >> exit 1 > >> fi > >> > >> +data_bg_zone_idx=5 > > > > Hmm. Yeah, it's currently there. But, I'd hesitate to use that like a > > constant number. > > > > Instead, how about querying "btrfs inspect-internal" like in > > get_data_bg() do? E.g, like this: > > > > # Assumes SINGLE data profile > > btrfs inspect-internal dump-tree -t CHUNK $SCRATCH_DEV | grep -A 4 CHUNK_ITEM |\ > > grep -A 3 'type DATA\|SINGLE' |\ > > grep -Eo 'offset [[:digit:]]+'| cut -d ' ' -f 2 > > > > This command dumps the location of data BG in a byte unit. > > > > Then, we can calculate the sector number and can supply it to "blkzone > > report -o". > > > Got it. I also prefer this over hardcoding. > I think we can reuse the get_data_bg function as it also outputs the > same data BG offset. No, we cannot. They look the same in number, but they are different in type. The get_data_bg returns the logical address (virtual btrfs's internal address) of the BG. And, my command above returns the physical address (on-disk address) of the BG. > Like this: > > start_data_bg_zone=$(get_data_bg) > start_data_bg_zone=$((data_bg_zone >> 9)) > > size=$($BLKZONE_PROG report -o $start_data_bg_zone -l 1 $SCRATCH_DEV |\ > ... > Let me know your thoughts. > >> +size=$($BLKZONE_PROG report -c $data_bg_zone_idx $SCRATCH_DEV | tail -1 |\ > >> + _filter_blkzone_report |\ > >> + grep -Po "cap ([0x\d]+)+" | cut -d ' ' -f 2) > >> +size=$((size << 9)) > >> + > >> reclaim_threshold=75 > >> echo $reclaim_threshold > /sys/fs/btrfs/"$uuid"/bg_reclaim_threshold > >> fill_percent=$((reclaim_threshold + 2)) > >> rest_percent=$((90 - fill_percent)) # make sure we're not creating a new BG > >> -fill_size=$((zonesize * fill_percent / 100)) > >> -rest=$((zonesize * rest_percent / 100)) > >> +fill_size=$((size * fill_percent / 100)) > >> +rest=$((size * rest_percent / 100)) > >> > >> # step 1, fill FS over $fillsize > >> $XFS_IO_PROG -fc "pwrite 0 $fill_size" $SCRATCH_MNT/$seq.test1 >> $seqres.full > >> -- > >> 2.25.1 > > -- > Regards, > Pankaj
