diff options
| author | Mike Christie <michael.christie@oracle.com> | 2025-09-17 17:12:55 -0500 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2025-11-02 22:06:12 -0500 |
| commit | bbb490053173b737604a87af03f2113fb1c279a0 (patch) | |
| tree | d9432a07971601b78189efc93d807d49e5cf65d2 /include/target | |
| parent | ed6b97a79577db9bf9d7b21fd623f24f499e3acc (diff) | |
scsi: target: Move LUN stats to per-CPU
The atomic use in the main I/O path is causing perf issues when using
higher performance backend devices and multiple queues (more than
10 when using vhost-scsi) like with this fio workload:
[global]
bs=4K
iodepth=128
direct=1
ioengine=libaio
group_reporting
time_based
runtime=120
name=standard-iops
rw=randread
numjobs=16
cpus_allowed=0-15
To fix this issue, move the LUN stats to per CPU.
Note: I forgot to include this patch with the delayed/ordered per CPU
tracking and per device/device entry per CPU stats. With this patch you
get the full 33% improvements when using fast backends, multiple queues
and multiple IO submiters.
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Reviewed-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
Link: https://patch.msgid.link/20250917221338.14813-4-michael.christie@oracle.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'include/target')
| -rw-r--r-- | include/target/target_core_base.h | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index 27e1f9d5f0c6..372da2eadf54 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -744,9 +744,9 @@ struct se_port_stat_grps { }; struct scsi_port_stats { - atomic_long_t cmd_pdus; - atomic_long_t tx_data_octets; - atomic_long_t rx_data_octets; + u64 cmd_pdus; + u64 tx_data_octets; + u64 rx_data_octets; }; struct se_lun { @@ -773,7 +773,7 @@ struct se_lun { spinlock_t lun_tg_pt_gp_lock; struct se_portal_group *lun_tpg; - struct scsi_port_stats lun_stats; + struct scsi_port_stats __percpu *lun_stats; struct config_group lun_group; struct se_port_stat_grps port_stat_grps; struct completion lun_shutdown_comp; |