On Mon, Oct 15, 2012 at 10:17 AM, Jan Steinman <Jan(a)bytesmiths.com> wrote:
From: David
Gerard <dgerard(a)gmail.com>
The MW file cache might be fast, but Squid is
always going to be faster.
We're quite fond of our "This article has been viewed x times" at the
bottom of the pages, though I'm quite aware that's an expensive
affectation that we may well have outgrown.
I think it's just a simple database query. At least I have a
"mw_hitcounter" MEMORY table in my database. But maybe it's leftover cruft
from past upgrades...
There's a lot more to it than that, and it is indeed a performance
drain (which is why we don't use it at WMF). Each pageview
writes to the hitcounter table. Every so often the page table is
updated with the hits from hitcounter.
Sure, displaying the hits is a simple query to the page table,
but updating hitcounter each pageview just does not scale.
-Chad