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David Burgess wrote:

FastCGI has a session affinity patch.

There have been significant periods when has been losing. I'm glad to see it's back online.

There are two ways of looking at session affinity.

One is that it is a fundamental way of structuring process flow. In this case, the lifetime of a process flow is tied to the lifetime of a particular FastCGI process. Life is relatively simple if you believe this.

The second is that session affinity is just a performance hack. In this view, a computational flow must be able to migrate across engines. You must be able to keep all of your interesting data in some shared repository, but it happens that most of the time you don't need to reinstantiate it.

I honestly don't know which of these I believe in. Given that users are already used to web apps breaking randomly ("Just Another Victim Of The Ambient Morality") it may make sense to punt on migration. The computational model in the second case can get arbitrarily complex, as you may need to do a full Pluto serialization into a db on every context switch---or wuss out, and declare that some tables (the persistent ones) are "special" in the pejorative sense and can only absorb scalars or acyclic tables of scalars. After a delightful bout with ASP where false ~= false, I'm willing to work with ANYTHING that wasn't designed by idiots.

At this point I'm about ready to give up on migration *and* naive session affinity, and force fit the programming model into wiki-on-drugs and call it a day. Oh, and run around quoting more Iain Banks ship names in comments.

-- A Frank Exchange Of Views
-- Grey Area
-- Very Little Gravitas Indeed