A softlockup occurs when some earlier versions of the Linux kernel write data back to file caches. This topic describes the cause of and solution to the issue.
514.26.2.el7.x86_64indicates that the kernel version is
[3507707.671883] [<ffffffff8127cf7a>] redirty_tail+0x3a/0x40 [3507707.671884] [<ffffffff81280ea4>] __writeback_inodes_wb+0x64/0xc0 [3507707.671885] [<ffffffff81281238>] wb_writeback+0x268/0x300 [3507707.671887] [<ffffffff812819f4>] wb_workfn+0xb4/0x380 [3507707.671889] [<ffffffff810a5dc9>] process_one_work+0x189/0x420 [3507707.671890] [<ffffffff810a625b>] worker_thread+0x1fb/0x4b0 [3507707.671891] [<ffffffff810a6060>] ? process_one_work+0x420/0x420 [3507707.671893] [<ffffffff810ac696>] kthread+0xe6/0x100 [3507707.671894] [<ffffffff810ac5b0>] ? kthread_park+0x60/0x60 [3507707.671897] [<ffffffff81741dd9>] ret_from_fork+0x39/0x50
When the memory of the instance is insufficient, the operating system kernel frequently
wakeup_flusher_threads function. When the function is called, a large number of writeback tasks (
wb_writeback_work) are created. As a result, the writeback threads keep processing the writeback tasks,
and a softlockup occurs on the operating system.
- Connect to the instance. For more information about how to connect to an instance, see Connection methods.
- Run the following command to view the kernel version of the operating system:
- If the kernel version is 4.15 and earlier, run the following command to update the
kernel version. If the kernel version is later than 4.15, the softlockup does not occur on the operating system. You do not need to perform the subsequent operations.
yum update kernel
- Restart the instance after you update the kernel version.
- After the instance is restarted, run the following command again to check whether
the kernel version is later than 4.15:
uname -rIf you cannot update some earlier versions of Linux kernels by running the yum update kernel command, download the kernel RPM package of a version later than 4.15 and manually upgrade the kernel RPM package.