Slow Initial Page Load

[zenticed]

I have seen a number of posts regarding slow page loads but can't seem to find an answer to my particular problem.

I am running a modified Zencart 1-2-7-d site.

Starting with a "clean" browser (cleared cache/cookies), on my first access to the site the initial page takes up to 8 secs to BEGIN to load (ie display). I'm not concerned with how long this initial page takes to complete loading, only how long it takes to begin to load.
On subsequent accesses (again first clearing browser cache/cookies), the initial page begins to load in under 2 seconds, which seems quite acceptable. Page parse times reflect these observations.
However if:-
(a) my current access is delayed by more than about 1 hour from my previous access, then the current access is again very slow, or,
(b) if at any time I drop my current IP address ( from my ISP) and get a new one, then the initial page load from my site is again very slow irrespective of the time I last accessed the site (with a former and different IP address).

I should mention that this effect doesn't seem to happen consistently from all access points (ie from different ISP's and at different times) but from quite a number so as to be disturbing.
From my own access location the problem is always present and I can demonstrate it consistently.

My hosting provider doesn't see any problems on his server ? My ISP likewise on their gear?


I would be grateful if someone could provide some help with this please as I am getting complaints from understandably frustrated users.

Thanks.

[Merlinpa1969]

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