And how many requests/sec per CPU?
They have like 300 servers and who knows how many cores.
What kind title is this? The target High Scalability reader must be presumed to be a complete fool.
They have like 300 servers and who knows how many cores.
What kind title is this? The target High Scalability reader must be presumed to be a complete fool.
So that averages out to: 70000 / (4 * 2000) = 8.75 requests per second per CPU.
That seems like quite a low number, I would presume that the load would be shared amongst less servers than this and the others would be used for replication/redundancy.
From the article it seems more like they have ~100, maybe less, for the load balancers which comes out to 175 requests/second per cpu which is getting a little more reasonable.
The point is the title is useless. It tells you almost nothing. That blog is a joke.
But yeah the title is pretty much useless.
Peter Westwood gave a talk on WP.com's infrastructure in London in January; I've tried to find slides online but I can't, which is a shame because he went into quite a bit of detail about their nginx/HyperDB/memcached/mogileFS setup.
http://wordpress.tv/2011/08/31/barry-abrahamson-ask-barry-ab...
I think we can safely assume each datacenter holds a dedicated load-balancing server. Let's assume they have only one of these at each datacenter, it gives us 70000 / (4 * 12) = 1460 requests per second per CPU, which is in line with reliably handling over 10,000 request per second of live traffic to WordPress applications from a single server.
and
In April 2008 Automattic converted all WordPress.com load balancers from Pound to NGINX. , which points to the fact that they're only talking about load balancers and they have several of them.
This link implies that one NGINX load-balancing instance cannot handle 70k r/s.
70 000 / (4 * 12 * 12) = 121.52 request per CPU