A person asks why their WordPress Online Shop has strangely become slow and they wonder if it could be due to recent plugin updates.
This is difficult to say what can be slowing your website.
Although updates to plugins can cause problems. Normally a plugin will work relatively the same from version to version. That means if you have not added a number of new plugins your site should be running about the same.
If you are on a shared hosting plan by a hosting provider you should look at your services and see if it is displaying low memory or high cpu use.
Some hosts also show your open processes and may have a limit on the number you can have running at any one time.
You want to check your Error Logs and Visitor Logs and see if your website is being visited by bots from google or other indexing sites.
You could also be under a brute force attack by hackers trying to get into your store.
And if you are on a shared host .. then other user websites could be slowing your website down.
Without reviewing your server logs and information it is too difficult to know from the outside.
I think the first thing I would do is look at your Access Logs to see where your visitors are coming from.
If you see that the top ten IPs or hostnames are using up 50% of your visits then you should find out who they are.
If it is Google Indexing your website you probably don’t want to block them or rate limit them but there could be a point where you simply have to block google. Start a Google Analytics account and you can learn more about that but I strongly suggest you do not limit google.
If you find that it is some random server in a country you have no ties to and they are not owned by a search engine .. block that IP and its class.
If the IP is 123.123.123.18 you should block 123.123.123.1 to 255 … normally that is done by using 123.123.123. and then the server will know to block that whole segment of IPs.
But if it is a distributed attack with many ips you will have to contact your hosting company for extended help that they can implement on their routers rather than on the servers.