Safari loads very slow after awhile

Using 2015 iMac with max specs… Everything works fine, except after using Safari for awhile, pages start loading VERY slowly (takes 30 seconds or more). I’ve tried clearing cache, cookies, etc, but only thing that seems to help is a reboot… then fine again for 3-4 days until it happens again. Admittedly, I do have typically 10-15 tabs open at a time, but nothing taking up a ton of CPU (and CPU overall is fine per iStat menus). Chrome doesn’t have this issue… any suggestions most welcome!

Flush the DNS Cache

sudo killall -HUP mDNSResponder; sleep 2; echo macOS DNS Cache Reset | say

Thanks- will give this a try next time, though I’ve also tried Clean My Mac which I think did this… cannot tell from your line- does the terminal command end the word Cache or Reset?! (I’m guessing it doesn’t go to “I say” )

This should do the same: Clean My Mac > Maintenanance > Flush DNS Cache

You might want to take a look at your network router, could be that things get clogged up inthere as well…

It ends with the word say. The echo command tells your computer to put some text on the screen; the pipe | which follows tells your computer to take the results of the echo command and send it to the say command. This is simply so that your computer alerts you that it has finished doing the first command before the semi-colon (flushing the cache).

Well, it just happened, and sadly, that terminal command did not fix the safari problem (which I suspected, given I’ve used Clean my Mac before to try and clear cache, etc)… Just entered URL for my bank, and took about 30 seconds to load. Interestingly, once it loads, subsequent sites within the bank site load normally. But a completely different site again loads slowly, until reboot.

Is this a Safari specific issue? In other words, if Safari is being slow and you fire up another browser (Chrome, for instance) will it also be slow, or is this just something that affects Safari?

Definitely JUST safari. Chrome works normally. (But Safari is my main browser)