Bug ID 424931: Creating or copying large files may cause the csyncd service to spike CPU utilization.

Last Modified: Oct 16, 2023

Affected Product(s):
BIG-IP LTM(all modules)

Known Affected Versions:
10.0.0, 10.0.1, 10.1.0, 10.2.0, 10.2.1, 10.2.2, 10.2.3, 10.2.4, 11.0.0, 11.6.0 HF1, 11.6.0 HF2, 11.6.0 HF3, 11.6.0 HF4, 11.6.0 HF5, 11.6.0 HF6, 11.6.0 HF7, 11.6.0 HF8, 11.5.1 HF1, 11.6.1 HF1, 11.5.1 HF2, 11.6.1 HF2, 11.5.1 HF3, 11.5.1 HF4, 11.5.1 HF5, 11.6.2 HF1, 11.1.0, 11.2.0, 11.2.1, 11.3.0, 11.4.0, 11.4.1

Fixed In:
11.6.0, 11.5.1 HF6, 11.4.1 HF6, 11.2.1 HF16

Opened: Jul 10, 2013

Severity: 4-Minor

Related Article: K15710

Symptoms

Creating or copying large files may cause the csyncd service to spike CPU utilization. As a result of this issue, you may encounter one or more of the following symptoms: BIG-IP iHealth lists Heuristic H484968 on the Diagnostics > Identified > High screen. CPU utilization may spike to 90-100 percent. Using the Linux command line utility top to view the csyncd service CPU utilization shows the csyncd service using a high percentage of CPU right after you have created a large file. For example, type the following command: top | egrep '%CPU|csyncd' You see output similar to the following example: PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 7179 root 20 0 32028 17m 10m S 1.7 0.2 8:45.50 csyncd 7179 root 20 0 32028 17m 10m S 1.7 0.2 8:45.55 csyncd 7179 root 20 0 32028 17m 10m S 1.7 0.2 8:45.60 csyncd 7179 root 20 0 32028 17m 10m R 20.9 0.2 8:46.23 csyncd 7179 root 20 0 32028 17m 10m R 96.9 0.2 8:49.15 csyncd 7179 root 20 0 32028 17m 10m R 96.6 0.2 8:52.06 csyncd 7179 root 20 0 32028 17m 10m R 96.6 0.2 8:54.97 csyncd 7179 root 20 0 32028 17m 10m R 97.3 0.2 8:57.90 csyncd 7179 root 20 0 32028 17m 10m R 97.3 0.2 9:00.83 csyncd 7179 root 20 0 32028 17m 10m R 96.6 0.2 9:03.74 csyncd 7179 root 20 0 32028 17m 10m R 97.0 0.2 9:06.66 csyncd 7179 root 20 0 32028 17m 10m R 97.3 0.2 9:09.59 csyncd 7179 root 20 0 32028 17m 10m R 97.0 0.2 9:12.51 csyncd 7179 root 20 0 32028 17m 10m R 96.9 0.2 9:15.43 csyncd 7179 root 20 0 32028 17m 10m S 15.9 0.2 9:15.91 csyncd 7179 root 20 0 32028 17m 10m S 1.3 0.2 9:15.95 csyncd 7179 root 20 0 32028 17m 10m S 2.0 0.2 9:16.01 csyncd 7179 root 20 0 32028 17m 10m S 1.3 0.2 9:16.05 csyncd

Impact

Extended high CPU utilization can degrade performance, and the system may eventually become unresponsive or reboot.

Conditions

This issue occurs when the following condition is met: You have created or copied a large file to a directory monitored by the csyncd service. Note: The CPU utilization spike length correlates directly to the large file size and the capacity of the BIG-IP system.

Workaround

None.

Fix Information

Creation of a large file, such as a UCS archive is now handled correctly, and csyncd process no longer causes high CPU utilization.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips