Its weird cause the other menu's are still being served from the CDN unless it had to go to the server to fetch.. then it should have hit varnish cache... but once you been to the menu once it will cache it on your browser so it will be quick to click on the same menu again.
If your logged in there is no caching since cookies are stored for authentication.
I run a ubuntu server too, but not yet with SSD.
Would you say that it's worth it to change to SSD?
Internetspeed is so much dependend on other things too... not just the harddisk type...
Sure thats why I used all of those other cache's and optimizations I told you... but SSD helps.. Varnish is storing its cache on a 1gb cache file while object cache and page cache is done using memcacheD.... so varnish allows for a bigger cache but uses SSD to do its thing.. but seems as though its not much slower than using memory...
In the end SSD prices compete with VPS im paying $5 per month better than my blue host price which was slow... DNS was taking 2 seconds to resolve.. screw that. Cloudflare DNS is the best.