| Message ID | 20220610021701.2347602-1-yukuai3@huawei.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | support concurrent sync io for bfq on a specail occasion | expand |
Hi, Paolo Can you take a look at this patchset? Thanks, Kuai 在 2022/06/10 10:16, Yu Kuai 写道: > There are some problem in our mail server, resend v9 because Paolo seems > didn't receive them(hopefully v10 will be fine). > > Changes in v10: > - Add reviewed-tag for patch 2 > > Changes in v9: > - also update how many bfqqs have pending_reqs bfq_bfqq_move(). > - fix one language in patch 4 > - Add reviewed-tag for patch 1,3,4 > > Changes in v8: > - Instead of using whether bfqq is busy, using whether bfqq has pending > requests. As Paolo pointed out the former way is problematic. > > Changes in v7: > - fix mismatch bfq_inc/del_busy_queues() and bfqq_add/del_bfqq_busy(), > also retest this patchset on v5.18 to make sure functionality is > correct. > - move the updating of 'bfqd->busy_queues' into new apis > > Changes in v6: > - add reviewed-by tag for patch 1 > > Changes in v5: > - rename bfq_add_busy_queues() to bfq_inc_busy_queues() in patch 1 > - fix wrong definition in patch 1 > - fix spelling mistake in patch 2: leaset -> least > - update comments in patch 3 > - add reviewed-by tag in patch 2,3 > > Changes in v4: > - split bfq_update_busy_queues() to bfq_add/dec_busy_queues(), > suggested by Jan Kara. > - remove unused 'in_groups_with_pending_reqs', > > Changes in v3: > - remove the cleanup patch that is irrelevant now(I'll post it > separately). > - instead of hacking wr queues and using weights tree insertion/removal, > using bfq_add/del_bfqq_busy() to count the number of groups > (suggested by Jan Kara). > > Changes in v2: > - Use a different approch to count root group, which is much simple. > > Currently, bfq can't handle sync io concurrently as long as they > are not issued from root group. This is because > 'bfqd->num_groups_with_pending_reqs > 0' is always true in > bfq_asymmetric_scenario(). > > The way that bfqg is counted into 'num_groups_with_pending_reqs': > > Before this patchset: > 1) root group will never be counted. > 2) Count if bfqg or it's child bfqgs have pending requests. > 3) Don't count if bfqg and it's child bfqgs complete all the requests. > > After this patchset: > 1) root group is counted. > 2) Count if bfqg has pending requests. > 3) Don't count if bfqg complete all the requests. > > With the above changes, concurrent sync io can be supported if only > one group is activated. > > fio test script(startdelay is used to avoid queue merging): > [global] > filename=/dev/sda > allow_mounted_write=0 > ioengine=psync > direct=1 > ioscheduler=bfq > offset_increment=10g > group_reporting > rw=randwrite > bs=4k > > [test1] > numjobs=1 > > [test2] > startdelay=1 > numjobs=1 > > [test3] > startdelay=2 > numjobs=1 > > [test4] > startdelay=3 > numjobs=1 > > [test5] > startdelay=4 > numjobs=1 > > [test6] > startdelay=5 > numjobs=1 > > [test7] > startdelay=6 > numjobs=1 > > [test8] > startdelay=7 > numjobs=1 > > test result: > running fio on root cgroup > v5.18: 112 Mib/s > v5.18-patched: 112 Mib/s > > running fio on non-root cgroup > v5.18: 51.2 Mib/s > v5.18-patched: 112 Mib/s > > Note that I also test null_blk with "irqmode=2 > completion_nsec=100000000(100ms) hw_queue_depth=1", and tests show > that service guarantees are still preserved. > > Previous versions: > RFC: https://lore.kernel.org/all/20211127101132.486806-1-yukuai3@huawei.com/ > v1: https://lore.kernel.org/all/20220305091205.4188398-1-yukuai3@huawei.com/ > v2: https://lore.kernel.org/all/20220416093753.3054696-1-yukuai3@huawei.com/ > v3: https://lore.kernel.org/all/20220427124722.48465-1-yukuai3@huawei.com/ > v4: https://lore.kernel.org/all/20220428111907.3635820-1-yukuai3@huawei.com/ > v5: https://lore.kernel.org/all/20220428120837.3737765-1-yukuai3@huawei.com/ > v6: https://lore.kernel.org/all/20220523131818.2798712-1-yukuai3@huawei.com/ > v7: https://lore.kernel.org/all/20220528095020.186970-1-yukuai3@huawei.com/ > > > Yu Kuai (4): > block, bfq: support to track if bfqq has pending requests > block, bfq: record how many queues have pending requests > block, bfq: refactor the counting of 'num_groups_with_pending_reqs' > block, bfq: do not idle if only one group is activated > > block/bfq-cgroup.c | 10 ++++++++++ > block/bfq-iosched.c | 47 +++------------------------------------------ > block/bfq-iosched.h | 21 +++++++++++--------- > block/bfq-wf2q.c | 47 ++++++++++++++++++++++++++++++--------------- > 4 files changed, 57 insertions(+), 68 deletions(-) >