On 07.12.2017 00:58, Thomas Munro wrote:
> Using a ton of thread local variables may be a useful stepping stone,
> but if we want to be able to separate threads/processes from sessions
> eventually then I guess we'll want to model sessions as first class
> objects and pass them around explicitly or using a single TLS variable
> current_session.
>
It was my primary intention.
Unfortunately separating all static variables into some kind of session
context requires much more efforts:
we have to change all accesses to such variables.
But please notice, that from performance point of view access to
__thread variables is not more expensive then access to static variable or
access to fields of session context structure through current_session.
And there is no extra space overhead for them.
--
Konstantin Knizhnik
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