CPU High

[waversky]

Description

我在自己的电脑上安装了CouchDB ，用于学习，这大概是一个月前，最近我的电脑有点卡，今天发现是由erl.exe CPU(70%左右)占用过高导致的，它让电脑的CPU一直保持在100%，它来自“Apache CouchDB\erts-11.2.2.12\bin” 这个目录
I installed CouchDB on my computer for learning. About a month ago, my the computer is a little laggy recently had a bit of cards. Today, I found that it was due to the high CPU(about 70%) usage of CouchDB, It keeps the CPU of the computer at 100%，它来自“Apache CouchDB\erts-11.2.2.12\bin”这个目录

之后，我结束了“erl.exe” 进程，过了几秒，它又被唤起了，不过现在CPU占用维持在很低的水平
After that, I ended the "erl. exe" process. After a few seconds, it was awakened again, but now the CPU usage is kept at a very low level

我查看了本地的CouchDB，没有活跃的任务
I checked the local CouchDB and found no active tasks

Steps to Reproduce

我不知道怎么重现，但是我还是想报告这个问题
I don't know how to reproduce，But I still want to report this problem

Expected Behaviour

我最近没有关注自己电脑上的CouchDB ，它应该保持静默
I haven't paid attention to CouchDB on my computer recently. It should remain silent

Your Environment

• CouchDB version used: v. 3.2.2
• Browser name and version: Microsoft Edge 107.0.1418.35 (64 位)
• Operating system and version:windows 10 19044.2006 Intel(R) Core(TM) i5-7400

Additional Context

异常情况：
Exceptions:

进程重启后：
After the process restarts:

[big-r81]

Is there anything weird in your log files?

[waversky]

Is there anything weird in your log files?

This?

[big-r81]

Is this all in your logs?
Can you show your [log] config section?

[waversky]

I know nothing about erlang，You can tell me how to get logs，
I checked the configuration of these three files (default.ini、local.ini、local.ini.dist), and I'm sure they are all default, because each line starts with ";"

[waversky]

Today, the CPU usage of erl.exe soared again(about 30%). I ended its thread, but it immediately revived. After the revival, the CPU usage was about 20%. After several seconds, it dropped to a very low level. Now it is stable.

[waversky]

After Windows sleep for a weekend, activate Windows, erl.exe CPU usage reaches 50% - 70%, It may be related to the windows sleep switch

[big-r81]

Are there any active tasks in CouchDB while erl-CPU is high?

[waversky]

There are no active tasks. This may be a problem with Erlang or the Windows sleep mechanism. This happens every Monday morning when the computer wakes up.

[waversky]

[big-r81]

@waversky Hi, is this still a problem (with the latest version)?

[BeckmannM]

@big-r81: Are there any changes that may explain or fix this problem in recent versions? We are using version 3.1.0 and facing the same problem. In our scenario the couchdb is installed on windows surface tablets. Caused by the high cpu usage the tablets are getting uncomfortable warm. As waversky said, this appears when waking the tablet from standby. We have no aktive tasks or replications running.

[big-r81]

@BeckmannM Maybe you should try the latest version, there are many improvements (besides CVE fixes). The question is, what process is causing the high cpu usage and from which state ...

[BeckmannM]

I did a little research. I believe @waversky assumption is right and the problem is caused by windows sleep mode / fast start feature. I found some threads relating to the same problem with other software running with erlang. The suggested workaround is to disable windows fast start feature. I will try this and let you know.

Further informations:

• https://groups.google.com/g/rabbitmq-users/c/myl74gsYyYg
• https://erlang.org/pipermail/erlang-questions/2017-May/092256.html

[BeckmannM]

So i can confirm disabling windows fast start fixes the issue for us. This is a workaround only, but this solution is suitable for us. And it proves the cause is related to erlang/windows and no couchdb issue.

[big-r81]

It would be good to report this problem to the Erlang/OTP team.