自 ONTAP 9.3 以来,网络层出现 ONTAP 单个 LUN 延迟
适用场景
ONTAP 9.3及更高版本
问题描述
- 出现延迟的原因是 ONTAP 在 QoS statistics volume latency show 的网络层存在延迟。
- 从命令输出中观察到的高延迟:统计信息LUN show
cluster::> statistics lun show -lun <lun-path> -interval 5 -iterations 5
cluster: 3/29/2023 03:55:10
*Total Read Write Other Read Write Latency
Lun Vserver Ops Ops Ops Ops (Bps) (Bps) (us)
-------------------------------------------------------------------- ------------------- ------ ---- ----- -------------------------------------------
/vol/essspdb3_4_sppdbvg3_fc_vol03/essspdb3_4_sppdbvg3_fc_vol03_lun01DDCNTAPCL21_MCK_SAN 1310 1273 36 0 674478489 1435238 41402
- 读取吞吐量较高(可能接近 1 Gb/ 秒)
示例:
Cluster1::> qos statistics volume latency show -volume vol1lun1 -vserver svm1 Workload ID Latency Network Cluster Data Disk QoS NVRAM --------------- ------ ---------- ---------- ---------- ---------- ---------- ---------- ---------- -total- - 5.52ms 4.41ms 15.00us 981.00us 113.00us 0ms 0ms vol1lun1 10210 14.60ms 14.49ms 6.00us 91.00us 12.00us 0ms 0ms -total- - 4.08ms 3.68ms 13.00us 310.00us 71.00us 0ms 0ms vol1lun1 10210 15.56ms 15.47ms 39.00us 54.00us 1.00us 0ms 0ms -total- - 4.34ms 3.76ms 14.00us 483.00us 85.00us 0ms 0ms vol1lun1 10210 78.37ms 77.86ms 10.00us 430.00us 69.00us 0ms 0ms -total- - 5.08ms 4.44ms 15.00us 514.00us 109.00us 0ms 0ms vol1lun1 10210 86.62ms 85.86ms 5.00us 580.00us 174.00us 0ms 0ms Cluster1::> qos statistics volume performance show -volume vol1lun1 -vserver svm1 Workload ID IOPS Throughput Latency --------------- ------ -------- ---------------- ---------- -total- - 240958 2408.45MB/s 366.00us vol1lun1 10210 52416 1055.11MB/s 105.00ms -total- - 248647 2378.91MB/s 401.00us vol1lun1 10210 52516 1106.35MB/s 120.00ms -total- - 252124 2070.41MB/s 384.00us vol1lun1 10210 49125 995.11MB/s 108.00ms