In the current implementation, should_check_rate() returns false
if ddir_rw_sum(td->bytes_done)==0. Therefore, a thread may violate
the rate if iodepth*bs > rate.
This patch addresses the issue by not checking td->bytes_done in should_check_rate.
An example of the issue:
[root@localhost test]# cat fio_randwrite
[global]
thread
kb_base=1000
direct=1
size=28GiB
group_reporting
io_size=16384
ioengine=libaio
iodepth=2
bs=4096
iodepth_batch_submit=1
iodepth_batch_complete=1
filename=/dev/qblkdev
[fio_randwrite]
rw=randwrite
rate_iops=,1
iodepth_batch_submit=1
thinktime_blocks=1
rate_cycle=1000
thinktime=3s
rate_ignore_thinktime=1
[root@localhost test]# fio fio_randwrite
blktrace output:
259,1 11 1 0.
100550729 6135 Q WS
3541608 + 8 [fio]
259,1 11 2 0.
100552183 6135 G WS
3541608 + 8 [fio]
259,1 11 3 0.
100560373 6135 D WS
3541608 + 8 [fio]
259,1 11 4 0.
100570436 6135 C WS
3541608 + 8 [0]
259,1 11 5 0.
100599816 6135 Q WS
43470024 + 8 [fio]
259,1 11 6 0.
100600513 6135 G WS
43470024 + 8 [fio]
259,1 11 7 0.
100601579 6135 D WS
43470024 + 8 [fio]
259,1 11 8 0.
100612750 6135 C WS
43470024 + 8 [0]
259,1 11 9 3.
101034407 6135 Q WS
49511928 + 8 [fio]
259,1 11 10 3.
101036067 6135 G WS
49511928 + 8 [fio]
259,1 11 11 3.
101054487 6135 D WS
49511928 + 8 [fio]
259,1 11 12 3.
101068699 6135 C WS
49511928 + 8 [0]
259,1 11 13 6.
101267480 6135 Q WS
27599368 + 8 [fio]
259,1 11 14 6.
101269216 6135 G WS
27599368 + 8 [fio]
259,1 11 15 6.
101277050 6135 D WS
27599368 + 8 [fio]
259,1 11 16 6.
101287956 6135 C WS
27599368 + 8 [0]
Signed-off-by: HongweiQin <glqinhongwei@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>