Server suddenly overloaded after 2 weeks of usage

Hi there! As mentioned in title, I’ve been working with TD Composer to create a new theme for http://www.blog.qoo10.sg, testing and tweaking all on the live site for approximately the last two weeks. Last Friday, the whole website suddenly became very sluggish, at times timing out with server errors or bad request errors. We’ve increased the allocated resources on our AWS EC2 server, but our 4core CPU is still being almost maxed out by this operation.

Enabling or disabling the TagDiv Speed Booster plugin has almost no effect on this issue. However, the console log also shows TagDiv plugins generating a lot of errors, possibly adding to the overload.

`
2019/08/19 13:39:37 [error] 2339#0: *2 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 74.208.182.114, server: , request: “GET /search/1/page/8/tagDiv.com/page/page/tagDiv.com/page/tagDiv.com/page/page/10/ HTTP/1.1”, upstream: “fastcgi://127.0.0.1:9000”, host: “blog.qoo10.sg”, referrer: “-1); waitfor delay ‘0:0:3’ –”
2019/08/19 13:39:37 [error] 2336#0: *12 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 74.208.182.114, server: , request: “GET /search/1/page/8/tagDiv.com/page/page/tagDiv.com/page/tagDiv.com/page/page/ HTTP/1.1”, upstream: “fastcgi://127.0.0.1:9000”, host: “blog.qoo10.sg”, referrer: “http://blog.qoo10.sg/”
2019/08/19 13:39:37 [error] 2336#0: *11 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 74.208.182.114, server: , request: “GET /search/1/page/8/tagDiv.com/page/page/tagDiv.com/page/tagDiv.com/page/page/2/ HTTP/1.1”, upstream: “fastcgi://127.0.0.1:9000”, host: “blog.qoo10.sg”, referrer: “http://blog.qoo10.sg/”
2019/08/19 13:39:37 [error] 2336#0: *7 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 74.208.182.114, server: , request: “GET /search/1/page/8/tagDiv.com/page/page/tagDiv.com/page/tagDiv.com/page/page/2/ HTTP/1.1”, upstream: “fastcgi://127.0.0.1:9000”, host: “blog.qoo10.sg”, referrer: “http://blog.qoo10.sg/”
2019/08/19 13:39:37 [error] 2336#0: *13 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 74.208.182.114, server: , request: “GET /search/1/page/8/tagDiv.com/page/page/tagDiv.com/page/tagDiv.com/page/page/3/ HTTP/1.1”, upstream: “fastcgi://127.0.0.1:9000”, host: “blog.qoo10.sg”, referrer: “http://blog.qoo10.sg/”
`

Would greatly appreciate any advice or help you can offer on this matter.

Thank you! Other unnecessary plugins were not active, but CPU usage went back to normal after completely deleting them. All good for now!