Skip to main content
NetApp Knowledge Base

NFS file copy operations are slow due to packet loss and TCP retransmissions

  1. Last updated
  2. Save as PDF
Views:
73
Visibility:
Public
Votes:
0
Category:
ontap-9
Specialty:
nas
Last Updated:

Applies to

  • ONTAP 9
  • NFS 
  • Linux NFS clients

Issue

  • Users experience significant performance degradation when accessing data on specific NFS shares.
  • Copying files from the NFS export to local directories taks significantly longer than expected.
  • A 1 GB file copy operation that normally completed within 30 seconds to 2 minutes takes much longer e.g 30 minutes or 1.5 hours.
  • Basic filesystem operations such as ls experience delays of 10 to 15 seconds, whereas they previously completed almost instantly.
  • Wireshark filter  tcp.analysis.fast_retransmission or tcp.analysis.retransmission or tcp.analysis.out_of_order or tcp.analysis.duplicate_ack shows repeated retransmissions of traffic
  • Client-side connectivity tests line ping show packet
    •  100 packets transmitted, 83 received, 17% packet loss
  • ONTAP performance statistics indicated normal storage latency and CPU utilization during the affected timeframe, with no signs of a storage-side bottleneck.

Sign in to view the entire content of this KB article.

New to NetApp?

Learn more about our award-winning Support

NetApp provides no representations or warranties regarding the accuracy or reliability or serviceability of any information or recommendations provided in this publication or with respect to any results that may be obtained by the use of the information or observance of any recommendations provided herein. The information in this document is distributed AS IS and the use of this information or the implementation of any recommendations or techniques herein is a customer's responsibility and depends on the customer's ability to evaluate and integrate them into the customer's operational environment. This document and the information contained herein may be used solely in connection with the NetApp products discussed in this document.