Socket functions do not always honor deadline about userver HOT 3 OPEN

Checking for deadline is not very cheap. Checking it before each socket operation could degrade performance quite a lot.

Are you describing a theoretical problem or the current behavior does harm in some practical case?

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or the current behavior does harm in some practical case?

Well, depends on what one would consider 'harmful', but i would argue that the current behavior it not consistent with other parts of the framework: i as developer strongly expect a function that takes deadline as a parameter to be a 'deadline-point', which takes the burden of checking a deadline from me.

Are you describing a theoretical problem ...

Mostly, but i remember being surprised by this when testing clickhouse driver.


Say you have following logic (in pseudocode):

void SendUntilDeadline(deadline) {
    while (true) {
        some_data = GenerateSomeData();
        socket.SendSome(some_data, deadline);
    }
}

One could assume that this function stops execution when deadline is reached, but it might go well beyond if receiving side can keep up


I understand that checking deadline before each socket operation is costly, but what's your opinion on checking deadline once as early as possible, before going into while (io_func) loop?

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@apolukhin bump

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