PowerScale:由于 ICAP 服务器过载导致的 NFS 性能问题

Summary: 启用防病毒扫描设置“打开时扫描”或“关闭时扫描”时,NFS 性能会受到影响,导致 ICAP 服务器过载。

This article applies to This article does not apply to This article is not tied to any specific product. Not all product versions are identified in this article.

Symptoms

本知识库文章中描述的对 NFS 的性能影响适用于配置了 ICAP 服务器的群集。首先,检查 ICAP 防病毒服务器设置:
 

# isi antivirus icap settings view
 
           Fail Open: Yes
        Glob Filters: -
Glob Filters Enabled: No
Glob Filters Include: No
       Path Prefixes: /ifs/nasprod2024/smb
              Repair: No
       Report Expiry: 1W
       Scan On Close: Yes       <<<-- Enabled
        Scan On Open: Yes     <<<-- Enabled
Scan Cloudpool Files: No
   Scan Size Maximum: 100.00M
             Service: Yes
          Quarantine: Yes
            Truncate: No



确认在常规性能脚本中等待“av”或“av_wait”的 nfs 线程。
https://confluence.cec.lab.emc.com/display/ISILON/General+Performance+Troubleshooting
 

>>> Wait Channel Values<<<
11 av_wait
20 kqread
20 av
4 sbwait
1 opwres
4 sigwait
107 ucond


在受影响节点上受影响时间段内的日志消息中进行确认。
 

  1. /var/log/messages 中的 ICAP 服务器重载消息
     
2025-05-06T17:42:20.639078-07:00 <0.5> nasprod2024-4(id4) /boot/kernel.amd64/kernel: [bam_av.c:1176](pid 14848="nfs")(tid=100543) Scan 1:155d:543d::HEAD failed with timeout (probably due to ICAP server overload); doing opdata cleanup with state: dequeued
2025-05-06T17:42:20.639138-07:00 <0.5> nasprod2024-4(id4) /boot/kernel.amd64/kernel: [bam_av.c:1176](pid 14848="nfs")(tid=100524) Scan 1:0c2e:9531::HEAD failed with timeout (probably due to ICAP server overload); doing opdata cleanup with state: dequeued
 
 
  1. Avscan 取芯并重新启动 n /var/log/messages 

 

2025-05-06T17:00:03.571382-07:00 <0.5> nasprod2024-1(id1) /boot/kernel.amd64/kernel: /lib/libthr.so.3:_pthread_create+0x906
2025-05-06T17:00:03.571392-07:00 <0.5> nasprod2024-1(id1) /boot/kernel.amd64/kernel: --------------------------------------------------
2025-05-06T17:00:03.571403-07:00 <0.6> nasprod2024-1(id1) /boot/kernel.amd64/kernel: pid 68624 (isi_avscan_d), jid 0, uid 0: exited on signal 11 from pid 0 (unknown) (core dumped)
2025-05-06T17:00:03.905443-07:00 <3.3> nasprod2024-1(id1) isi_avscan_d[63725]: [0x4d07b71b3000] Setting process flag P_NO_SEMLOCK for avscan
2025-05-06T17:00:03.905857-07:00 <3.4> nasprod2024-1(id1) isi_avscan_d[63725]: [0x4d07b71b3000] isi_avscan_d starting up
2025-05-06T17:00:03.949657-07:00 <3.4> nasprod2024-1(id1) isi_avscan_d[63725]: [0x4d07b71b3000] isi_avscan_d completed start up, ready...

 

  1. Avscan 日志显示 ICAP 服务器过载的迹象
     
2025-05-06T17:38:58.867768-07:00 <3.6> nasprod2024-1(id1) isi_avscan_d[63725]: [0x4d07b7998200] Scan request timeout exceeded and dropped for 1:17c5:0b6e::HEAD, policy id: SCAN_ON_OPEN, report id: SCAN_ON_OPEN.
2025-05-06T17:38:58.868241-07:00 <3.6> nasprod2024-1(id1) isi_avscan_d[63725]: [0x4d07b71b4900] Scan request timeout exceeded and dropped for 1:17b7:6f7d::HEAD, policy id: SCAN_ON_OPEN, report id: SCAN_ON_OPEN.
2025-05-06T17:38:58.868439-07:00 <3.6> nasprod2024-1(id1) isi_avscan_d[63725]: [0x4d07b7997300] Scan request timeout exceeded and dropped for 1:0e78:89b3::HEAD, policy id: SCAN_ON_OPEN, report id: SCAN_ON_OPEN.


确认使用 isi_get 扫描的路径。例如,消息日志中的上述 LIN 1:0c2e:9531 应与 NFS 导出路径匹配。 
 

A valid path for LIN 1:0c2e:9531::HEAD is /ifs/nasprod2024/nfs/libarc-p1/mysql/#ib_16384_0.dblwr

Cause

客户的 ICAP 服务器在打开和关闭时会因扫描文件而过载。ICAP 指南建议至少为 1:1 的比率。

PowerScale OneFS CLI 管理指南 — ICAP 服务器


 

Resolution

要立即缓解问题,请禁用“打开时扫描”,然后测试性能。
 

# isi antivirus icap settings modify --scan-on-open=false


如果问题仍然存在,请禁用“关闭时扫描”,然后测试性能。
 

# isi antivirus icap settings modify --scan-on-close=false


对于永久解决方案,如果希望同时启用这两个设置,则增加 ICAP 服务器的数量。

关闭时扫描是建议的 1:1 ICAP 服务器与节点比率。

开放时扫描是建议的 2:1 ICAP 服务器与节点比率。 

Affected Products

Isilon, PowerScale OneFS
Article Properties
Article Number: 000328556
Article Type: Solution
Last Modified: 30 Sep 2025
Version:  2
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