This patch adds completion batching to the IRQ path. It reuses batch
completion code of virtblk_poll(). It collects requests to io_comp_batch
and processes them all at once. It can boost up the performance by 2%.
To validate the performance improvement and stabilty, I did fio test with
4 vCPU VM and 12 vCPU VM respectively. Both VMs have 8GB ram and the same
number of HW queues as vCPU.
The fio cammad is as follows and I ran the fio 5 times and got IOPS average.
(io_uring, randread, direct=1, bs=512, iodepth=64 numjobs=2,4)
Test result shows about 2% improvement.
4 vcpu VM | numjobs=2 | numjobs=4
-----------------------------------------------------------
fio without patch | 367.2K IOPS | 397.6K IOPS
-----------------------------------------------------------
fio with patch | 372.8K IOPS | 407.7K IOPS
12 vcpu VM | numjobs=2 | numjobs=4
-----------------------------------------------------------
fio without patch | 363.6K IOPS | 374.8K IOPS
-----------------------------------------------------------
fio with patch | 373.8K IOPS | 385.3K IOPS
Signed-off-by: Suwan Kim <suwan.kim027@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Message-Id: <20221221145456.281218-3-suwan.kim027@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
07b679f70d