Why do the resources go maximum when a new post is published on WordPress Blog?

[Samantha]

Hi
I use Shared hosting for my blog site with 1k/daily traffic when I publish a post on my Blog, the I/O usage and other resource usages go at maximum and the website goes down and it stays longer to go back to normal. Why is this issue happening? Should I upgrade to VPS?

[Keeran]

If you are using hosting from a well-known host, the issue shouldn't be at the host. As per my knowledge, every time an issue was generated due to some plugins.
I would recommend disabling all the plugins, then posting blogs whilst enabling the plugins one by one.
If you have 10 plugins, you disable all of them and start posting with 1 plugin enabled, if the I/O usage doesn't go crazy enable one more and post again, and so on.

[pravinD]

These shared server limits are unreal. Depending on the host, there will be 500 to 1000 accounts with these limits on the same servers, and some of the servers will have 64 to 128 GB of ram for the entire server.

You could try to reduce resource usage by disabling some plugins that may interfere with post publishing and then attempting to publish the post.