Alex Ellis (OpenFaaS Ltd) 1d07fda0a4 Wait for a function to become healthy in scale-up event ...

Prior to this change, after scaling a function up and
returning the API call, a function may still not be ready to
serve traffic. This resulted in HTTP errors, for a percentage
of the time, especially if the task was deleted instead of
being just paused.

Pausing was instant, but during re-creation the function needs
some time to start up.

This change puts a health check into the hot path for the
scale event. It is blocking, so scaling up will have some
additional latency, but will return with a ready endpoint
much more of the time than previously.

This approach means that faasd doesn't have to run a set of
exec or HTTP healthchecks continually, and use CPU for
each of them, even when a function is idle.

Tested with the nodeinfo function, by killing the task
and then invoking the function. Prior to this, the
function may give an error code some of the time.

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

2021-11-01 11:00:39 +00:00

..

collect.go

Add log shim and collect command

2020-02-23 19:54:49 +00:00

install.go

Fix for #201

2021-09-15 19:49:28 +01:00

provider.go

Wait for a function to become healthy in scale-up event

2021-11-01 11:00:39 +00:00

root.go

Update faasd main help message

2021-03-11 21:08:28 +00:00

up.go

Document APIs

2020-09-18 12:02:56 +01:00